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Scuba Forum / Scuba Locations / August 2005Cruise Ship Dive Excursions
I am an experienced diver (over 20 years but just recently got certified) who has never dove anywhere but New England. I am planning a cruise next February (the main reason I finally got certified) to the Caribbean. I hate to admit it but I'm one of those "Mike Nelson/Sea Hunt" guys who has some pretty old (but always serviced) equipment. I am using an old Sherwood regulator (with no safe 2nd stage) & wonder if the cruise ship excursion dives will even allow me to use this for their dives? (I already plan on bringing my own mask, snorkel & fins) Any other advise/experiences diving on cruise ship excursions would be appreciated. (My local dive shop recommended that I stick with these excursions as the boat won't sale without me if the dive boat returns late!) While most of the excursions boast a 2 tank dive, my fear is that they will chase us out of the water after 20 minutes per tank! > I am an experienced diver (over 20 years but just recently got certified) That is an unfathomable statement to me. :) > who has never dove anywhere but New England. I am planning a cruise next > February (the main reason I finally got certified) to the Caribbean. Sounds like an inexperienced newbie to me, at least in the warm water diving environment. > I hate > to admit it but I'm one of those "Mike Nelson/Sea Hunt" guys who has some [quoted text clipped - 3 lines] > bringing my own mask, snorkel & fins) Any other advise/experiences diving > on cruise ship excursions would be appreciated. Now I get it. You are experienced in cutting your buddy's hose when you are low on air; or use a full tank for jet propulsion under water, right? Rent ALL you equipments!! For cruiseship pods, they don't even cost anything extra, in many cases. I always carry my own gears knowing that I am subsidizing people like you when I dive with the cruiseship arranged "scuba excursions". >(My local dive shop > recommended that I stick with these excursions as the boat won't sale > without me if the dive boat returns late!) Good advise, but not necessarily the right reason. > While most of the excursions boast a 2 tank dive, my fear is that they will > chase us out of the water after 20 minutes per tank! Unlikely unless Mike Nelson is there cutting everyone's hoses. -- Bob. "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his keyboard resulting in: :Sounds like an inexperienced newbie to me, at least in the warm water :diving environment. Let's be realistic about this. If you can dive in cold water, you can dive in warm water. Dan Bracuk If we don't succeed, we run the risk of failure. > "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his > keyboard resulting in: [quoted text clipped - 3 lines] > Let's be realistic about this. If you can dive in cold water, you can > dive in warm water. Heehee ... I am seeing history repeat itself!! That was what Dave Waller (PADI instructor) said in 1989, soon joined another PADI instructors (Nick Simicich, who even had a rec.scuba FAQ) in engaging this Feeesh into my very first rec.scuba flamewar! :-) These two cold water wimps don't have ANY concept of proper weighting and buoyancy control that are ESSENTIAL in warm water diving. Dave was teaching his students to DUMP ALL AIR from their BC before surfacing, and then kick like hell to ascend -- instead of ascend slowly in NEUTRAL buoyancy without any kicking or unnecessary motion. So, we had a LONG flamewar about buoyancy control, proper weighting, etc. Nick Simicich was caught saying that HE (having done a little armchair physics calculation) that HE needed 45 lbs of lead to dive in COZUMEL, in the SUMMER -- while he was also busy flaming SDM magazine for its buoyancy articles and one of the Peter Hughes outfits that was running buoyancy control workshops. These are the COLD water divers that the warm water corals wish they could RUN. These are also the ones who said "if you can dive in cold water, you can dive anywhere" and then proceeded to DEVASTATE the warm water corals with their gloved paws, kicks, and uncontrollable buoyancy, and their total lack of DIVING SKILLS, especially in WARM water. Anymore words of wisdom about diving, Dan? :-) -- Bob. > > Let's be realistic about this. If you can dive in cold water, you can > > dive in warm water. [quoted text clipped - 17 lines] > busy flaming SDM magazine for its buoyancy articles and one of > the Peter Hughes outfits that was running buoyancy control workshops. Dave and Nick erased all their dirty footprints from google. The flamewar must have lasted three years. :-) Here's a piece of vintage Dave Waller, from 1991: http://tinyurl.com/8sd2n Using breath control to adjust for small depth changes is by now a well-known buoyancy control technique by WARM as well as COLD water divers! Listen to Dave: "During a typical dive profile a diver will change depth by as much a 10 feet, and modification of the amount of air in their BC will be required to maintain neutral buoyancy. The same cannot be achieved through breath control alone." This was an INSTRUCTOR. he couldn't control a change of depth by 10 feet by breath control! He must have a hell of lot air in his BC for being OVER_WEIGHTED -- which is typical of all cold water wimps! :-) Nick nuked most of his own posts (such as diving with 45 lbs of weight in Cozumel) that would make him a laughing stock for decades to come. By 1994, even HE has come around to admitting that COLD water divers (such as his former self), needed "help": NS> I'm slightly torn on this because I've certainly seen enough NS> bad buoyancy in my life, < like his own! LOL > NS> and I agree that many divers who have never dove in warm NS> water could use a bit of help weighting out. -- Bob. > These are the COLD water divers that the warm water corals wish > they could RUN. These are also the ones who said "if you can dive [quoted text clipped - 6 lines] > > -- Bob. "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his keyboard resulting in: :Anymore words of wisdom about diving, Dan? :-) I did my first hundred dives in cold water and my last 400 or so in warm. If you can dive in cold water, you can dive in warm. It is just so much easier. Dan Bracuk If we don't succeed, we run the risk of failure. > "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his > keyboard resulting in: [quoted text clipped - 5 lines] > If you can dive in cold water, you can dive in warm. It is just so > much easier. It's easier, alright. Not MUCH easier, if you DO IT RIGHT (not DIR). If you learn your cold water diving from the Bozos like Dave Waller and Nick Simicich, as I documented in my preceding posts in reply to you, then you would have been an incompetent diver, in Warm OR Cold water. I did my ICE diver cert in 1990. Can't get much colder than that. Because I was WARM water trained and was already an experienced WARM water diver, I had no trouble at all diving in drysuits, except the neck seals of the rental suit choked me (because it was 4" smaller than my neck seal should be. :-) So, I did my ice dives in my 1/4" wetsuit. BUOYANCY control is EVERYTHING in diving -- except it's a skill seldom acquired by the Cold-Water trained divers. The FIRST thing the ice diving instructor did in the pool session (on drysuit training) was to give me 30 lbs of lead after a quick look at me. I did a quick look at him, and handed back 15 of the 30 lbs. The 15 lbs was STILL too much lead, diving in that Viking drysuit. I had personally RESCUED some cold water trained divers in Cozumel (when they were sinking FAST) at 100 fsw and the DM was too far away tending to other clueless cold water divers. That one was only 20 lbs overweighted (in lead). The record I've seen was a New Joisey diver, who brought his own VEST (because no BELT could carry so much weight) and dived with 75 lbs of weight -- in his 1/4" wetsuit, in Cozumel. :-) When you're 10 lbs over-weighted, you are 15 lbs too heavy on decent because of the 5+ lbs of AIR in the full tank! So, you would have to pump air in the BC to compensate for the 15 lbs of overweight. Do a little Boyles Law stuff and you'll see why so many cold water diver shoot to the surface when they forget to lease air (or not release enough air) from their BC on ascent. In short, an inexperienced, cold water trained diver is much more dangerous (to THEMSELVES as well to his diving environment) than an inexperienced warm water diver -- because the latter is seldom as OVERWEIGHTED (in lead) as the former. Short Pop Quiz: How many Cold Water diver you know calibrate their "proper weight" (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How many of them even KNOW what their proper amount of lead SHOULD be? -- Bob. "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his keyboard resulting in: :BUOYANCY control is EVERYTHING in diving -- except it's a skill :seldom acquired by the Cold-Water trained divers. Buoyancy control is so much easier in warm water because of the thinner wetsuits. Dan Bracuk If we don't succeed, we run the risk of failure. I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of weights for his next dive!<G> (or.......the kind that are made of cement and you wear on your feet) >> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his >> keyboard resulting in: [quoted text clipped - 58 lines] > > -- Bob. > I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of > weights for his next dive!<G> (or.......the kind that are made of cement and > you wear on your feet) No need. I have over 100 lbs of lead picked up in Cozumel alone, dropped by divers like yourself, after I started giving what I picked up to the boat captains. I had found belts below 150 fsw that were too heavy for me to bring up because my BC had a MAXIMUM lift of 16 lbs, fully inflated (they don't make them anymore because it's too dangerous for divers like Dick). Other times I took the weights off the belt and distributed them for others to bring up. Dick, you have the gall to be a smartass -- who claimed to have dived for 20 years without any certification and then claimed to be an "experienced" diver when you had absolutely ZERO experience diving in warm water. You're the biggest hazard to yourself, the warm water environment, and the other divers who have the misfortune to dive with you. -- Bob. > >> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his > >> keyboard resulting in: [quoted text clipped - 58 lines] > > > > -- Bob. Did we forget to take our medications again Bob? >> I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of >> weights for his next dive!<G> (or.......the kind that are made of cement [quoted text clipped - 88 lines] >> > >> > -- Bob. > Did we forget to take our medications again Bob? Dickhead, Are you talking about yourself in your editorial "we"? Try something original, or at least lines that have not been used by Clueless Newbies like yourself a thousand times, to everyone who exposed their cluelessness. -- Bob. > >> I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of > >> weights for his next dive!<G> (or.......the kind that are made of cement [quoted text clipped - 88 lines] > >> > > >> > -- Bob. > BUOYANCY control is EVERYTHING in diving -- except it's a skill > seldom acquired by the Cold-Water trained divers. (Gently picking up the bait, feeling for any hook or line...) I beg to differ, Bob. Although most of my 769 dives didn't usually involve a buddy, I've observed dozens of different coldwater divers on numerous occasions, and they exhibited excellent buoyancy control, with the only exceptions being three or four divers who repeatedly don't or won't. All the others maintained neutral buoyancy quite well. They could suspend without any significant movement. They swam effortlessly without contacting the bottom or disturbing the bottom with jets of downward thrust. They didn't scull with their hands. They didn't hover like a vertical helo. They didn't drop down on the substrate unaware. They didn't float toward the surface out of control. They didn't have to constantly add and exhaust air to maintain buoyancy, so I assume they weighted themselves close to the optimum. > The FIRST thing the ice diving instructor did in the pool session > (on drysuit training) was to give me 30 lbs of lead after a quick > look at me. I did a quick look at him, and handed back 15 of > the 30 lbs. The 15 lbs was STILL too much lead, diving in that > Viking drysuit. 15 lbs is a remarkably low amount of lead, especially for a drysuit worn by an averaged size male, even with a very thin undergarment, assuming a typical single 80 aluminum tank. However, it may have seemed "STILL too much lead", as you said, if your pool dive didn't drain the tank much or if the undergarment was very thin. I've seen some of the old Viking undergarments and they are pretty thin. More suitable for above 50F active dives. In cold water, I certainly wouldn't have been warm enough in that thin an undergarment. I have a quick rule of thumb for ROUGHLY estimating weighting required by undergarments is to put them in a plastic bag and ball them up with a little compression and estimate the volume they will displace in the water. An undergarment that fits in a 2-gallon container might be a little thin for ice diving and alone may require 16 pounds to neutralize its buoyancy. Of course, in-water adjustment of weighting would be the last word. The real last word will be thermal loss and shaking chills with an inadequate undergarment or not enough weight to promote loft on the uppermost areas of the undergarment when horizontal. > How many Cold Water diver you know calibrate their "proper weight" > (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How > many of them even KNOW what their proper amount of lead SHOULD be? Most, from what I've seen, get it pretty close, perhaps within 2 lbs of the absolute minimum, but more likely a little further off. Very few of us are concerned about how little weight somebody else has on or if they've optimized their weighting. With a drysuit, which I use all year, proper amount of lead for me varies, as I'll change the amount of my insulation to match temp and activity level, even between dives sometimes. I might even add a couple lbs if my undergarments are a little damp from perspiration from the first dive, which might have made the end of the first dive a little chilly. Adding that little bit of extra weight can make the difference in warmth for the next dive. Of course, the trade-off is slightly more wasted air from adjusting for buoyancy changes during the dive. I make the weighting adjustments from experience of trial and error, occasionally referring to a log of what worked well to keep me warm with various combinations of undergarments, hoods, gloves, etc. I don't strive to get the optimum weighting for it's own sake because, frankly, with a drysuit, it's not as warm. Purists like to wear an abolute minimum of weight, but, in my drysuit, I find I'm warmer with about 4 extra pounds. I think that achieves better loft in the uppermost areas of the insulation when horizontal. The trade-off is a little more air wasted when adjusting for changes in buoyancy. Sure is nice to be warm as toast, though. With a wetsuit, in shallow water, the purists' absolute minimum may be more beneficial to reduce such waste of air, but that benefit is reduced at depths where suit compression requires more air to maintain neutral buoyancy. I think the purists' love of minimal weighting is best justified in warm water conditions which require minimimal thermal protection. Then the positive benefits would be pretty consistent. Dave C > > BUOYANCY control is EVERYTHING in diving -- except it's a skill > > seldom acquired by the Cold-Water trained divers. > > (Gently picking up the bait, feeling for any hook or line...) :-) Hi Dave. It's no bait. Serious stuff! > [quoted text clipped - 4 lines] > and they exhibited excellent buoyancy control, with the only exceptions > being three or four divers who repeatedly don't or won't. You've observed only dozens of divers? No wonder. I've observed HUNDREDSs of cold water and warm water divers in Cozumel on my first 100 dives there. I stopped counting my Cozumel dives after THAT total reached 1200 several years ago. > All the others maintained neutral buoyancy quite well. They could > suspend without any significant movement. They swam effortlessly [quoted text clipped - 4 lines] > to constantly add and exhaust air to maintain buoyancy, so I assume > they weighted themselves close to the optimum. Everything you said is quite plausible on what YOU observed. But your last line is patently false! A diver can be overweighted by 20 lbs and still exhibit what you saw, in cold OR warm water diving. *I* can't dive even 10 lbs overweighted. But most DMs in Cozumel can dive with 20 or 30 lbs extra (to carry lead that might be needed by divers OR pick up a dropped weightbelt) and still exhibit good buoyancy control. But that's divers in the OTHER extreme. That they can dive in spite of improper weighting. Proper weighting can ONLY be calibrated, carefully, IN WATER, by a diver who knows HOW. > > The FIRST thing the ice diving instructor did in the pool session > > (on drysuit training) was to give me 30 lbs of lead after a quick [quoted text clipped - 5 lines] > worn by an averaged size male, even with a very thin undergarment, > assuming a typical single 80 aluminum tank. At that time I was diving with 6 lbs in warm water. I weighed 190 lbs and wore a spare tire for natural insulation. :-) It was in a pool, hence no undergarment needed. The Viking suit itself has no buoyancy except for the air in it. A typical single 80AL has 5+ lbs of weight in its AIR over neutral. Thus, when I started with 15 lbs of lead, it was 20 lbs above neutral. I could have easily dived with 10 lbs of lead in that drysuit. > However, it may have seemed "STILL too much lead", as you said, if your > pool dive didn't drain the tank much or if the undergarment was very > thin. I've seen some of the old Viking undergarments and they are > pretty thin. More suitable for above 50F active dives. True. The thinsulate undergarb (what was used in actual ice dives) would have required another 10 lbs of lead or so. I had already factored the air in the tank into the lead I needed. > In cold water, I certainly wouldn't have been warm enough in that thin > an undergarment. [quoted text clipped - 3 lines] > a little compression and estimate the volume they will displace in the > water. That's a very bad "rule of thumb". That's not even proper physics! Proper calibration is no different for cold and warm water divers. Find out how much ACTUAL weight you'll need to remain neutral (with All air out of the BC) when you're doing your safety stop at 15 fsw with 500 psi. The most lead you need is the descent of the first 15 feet. Thereafter, no matter how thick your wetsuit is, it'll be compressed so much that you'll no longer need the "proper weight" -- which is why a heavy wetsuit wearer will need to pump a LOT of air into the BCD to compensate for the wetsuit compression at 100 feet, say! > An undergarment that fits in a 2-gallon container might be a little > thin for ice diving and alone may require 16 pounds to neutralize its [quoted text clipped - 12 lines] > Most, from what I've seen, get it pretty close, perhaps within 2 lbs of > the absolute minimum, but more likely a little further off. See, you're guessing, even for YOURSELF, judging from what you said about how you estimate your own needed lead. > Very few of > us are concerned about how little weight somebody else has on or if > they've optimized their weighting. Or their own. That's where WARM WATER WIMPS are much more "proper weight" oriented because of the ease and freedom to DIVE WELL, without all the cold water gear and needed extra weight! Ultra trim trim plus minimal and proper weighting improves AIR CONSUMPTION EFFICIENCY. That is one reason I can dive longer on one tank of air than most. I was so fined tuned that I could tell the difference in the salinity of the water between the Atlantic (Bahamas) and the Caribbean! I have custom-made 1/4 lb pieces of lead that inserts into my weightbelt. :-) Of course I had many 1 lb pieces too. I think a diver SHOULD be properly calibrated to within a couple of lbs. of the "proper weight". Most divers DON'T KNOW what that number is, period -- or how to calibrate it! > With a drysuit, which I use all year, proper amount of lead for me > varies, as I'll change the amount of my insulation to match temp and [quoted text clipped - 4 lines] > in warmth for the next dive. Of course, the trade-off is slightly more > wasted air from adjusting for buoyancy changes during the dive. I never quibble about any "couple of pounds" by anyone. It's the UNNEEDED 5, 10, or 20 lbs that are so commonly practiced by cold water divers that I crusade against. > I make the weighting adjustments from experience of trial and error, > occasionally referring to a log of what worked well to keep me warm > with various combinations of undergarments, hoods, gloves, etc. I don't > strive to get the optimum weighting for it's own sake because, frankly, > with a drysuit, it's not as warm. Proper weighting INCLUDES the consideration of proper (or chosen) warmth factor by the diver. So, if you needed 4 extra lbs for being WARMER, it's no different from someone wearing 7 mil instead of 5 mil (ro my 3 mil) to be sufficiently warm. BUt within EACH equipment (which includes the thickness of suit or the amount of insulation) there IS a "proper weight" that CAN be properly calibrated. It's the inadquacy of TRAINING agencies, which produced poorly trained Instructors, who in turn mis-taught proper weighting and buoyancy control, such as Nick Simicich and Dave Waller (the two I had used as examples) that led to students who pay no attention to over- weighting. It's that vicious cycle that needs to be corrected. > Purists like to wear an abolute minimum of weight, but, in my drysuit, > I find I'm warmer with about 4 extra pounds. I think that achieves [quoted text clipped - 6 lines] > reduced at depths where suit compression requires more air to maintain > neutral buoyancy. You used the term "purist" rather improperly, if I may say so. I don't mind being called a "purist" if you don't attach all the untrue and derogatory implications in what you wrote! :-) My LYCRA suit has NO COMPRESSION whether I am at 15 fsw or 199 fsw where I frequently visit. :) My 1.5 mil titanium was adequate even for my dives in Bali where I dived comfortably in 65-70F enjoying nearly 45 minutes of the one and only mola mola I've ever seen. The needed AIR in the BC is mostly to compensate for the 5 lbs of extra weight of the AIR in the tank at the beginning of the dive! > I think the purists' love of minimal weighting is best justified in > warm water conditions which require minimimal thermal protection. Then > the positive benefits would be pretty consistent. > > Dave C It's perfectly justified in diving with any equipment, in any cold water, at any temperature -- but you have to KNOW how to calibrate your minimum and calibrate it properly. That's the bottom line. -- Bob, > > > BUOYANCY control is EVERYTHING in diving -- except it's a skill > > > seldom acquired by the Cold-Water trained divers. Snip > > I beg to differ, Bob. > > [quoted text clipped - 4 lines] > > You've observed only dozens of divers? No wonder. Just trying to provide objective information. We're talking about two different things, though. Cold water divers in their element versus in a tropical setting. I took exception to your broad brush about cold water divers. In a tropical setting, maybe you're right that they're cocky or clueless and can't adjust their weighting. Just for the record, in my limited tropical experience, I readily adjusted to having 8 lbs or whatever it was with that 3mm shorty. 8^) > I've observed HUNDREDSs of cold water and warm water divers in > Cozumel on my first 100 dives there. I stopped counting my > Cozumel dives after THAT total reached 1200 several years ago. Since I'm observing these cold water divers in their element, perhaps I'm seeing more profiicient divers than the ones who hail from "cold water", but are on their warm water vacation. No doubt, being able to readjust weighting for tropical conditions and gear is the real issue, not the proficiency back home. > > All the others maintained neutral buoyancy quite well. SNIP They didn't have > > to constantly add and exhaust air to maintain buoyancy, so I assume > > they weighted themselves close to the optimum. > > Everything you said is quite plausible on what YOU observed. But > your last line is patently false! I should have specified I was thinking of our typical sawtooth profile where the overweighted diver will be intermittently purging copious amounts of air. That gets pretty obvious. As is the amount of inflation in the bcd. > A diver can be overweighted by 20 lbs and still exhibit what you > saw, in cold OR warm water diving. *I* can't dive even 10 lbs [quoted text clipped - 4 lines] > But that's divers in the OTHER extreme. That they can dive in > spite of improper weighting. If they changed depths significantly, you'd see their significant bcd adjustments, though, as they tried to maintain neutral. > Proper weighting can ONLY be calibrated, carefully, IN WATER, by > a diver who knows HOW. We're in agreement here, but I'm suggesting the optimum weighting isn't all that important. Wasted air is the primary issue. Being able to react quickly enough with breath control or power inflator is the other issue. 5 lbs excess weight shouldn't even present much of a problem except in shallow water for less experienced divers. So, maybe the real point is that optimal weighting makes it easier for newbies to maintain buoyancy. Experienced divers can adjust to overweighting better. > > > The FIRST thing the ice diving instructor did in the pool session > > > (on drysuit training) was to give me 30 lbs of lead after a quick > > > look at me. I did a quick look at him, and handed back 15 of > > > the 30 lbs. The 15 lbs was STILL too much lead, diving in that > > > Viking drysuit. I didn't think that the instructor would run you through the drill of feet first out-of-control ascent without an undergarment to make it more realistic. I'll bet the extra weight he suggested was to have the excess, expanding air in the suit require more effort to fin down and vent, either through somersault or push off the bottom maneuvers. That might have been his intent. By allowing you such little air in your suit, since you had no substantial undergarment and had reduced your weighting, that made it quite a bit easier, right? > > 15 lbs is a remarkably low amount of lead, especially for a drysuit > > worn by an averaged size male, even with a very thin undergarment, [quoted text clipped - 7 lines] > it was 20 lbs above neutral. I could have easily dived with 10 lbs > of lead in that drysuit. That all makes sense. Again, an undergarment would have been useful in simulating the feet-first out of control ascent and recovery because it would have provided more air and trapped the expanding air. > > I have a quick rule of thumb for ROUGHLY estimating weighting required > > by undergarments is to put them in a plastic bag and ball them up with [quoted text clipped - 6 lines] > All air out of the BC) when you're doing your safety stop at 15 fsw > with 500 psi. "ROUGHLY" estimating the weight required to neutralize buoyancy of some unfamiliar combination of undergarments can be very useful and time saving and get you within a few pounds of a good weight right off. The final fine-tuning can then be done quickly in-water. I didn't mean to imply that it's a primary on-going weighting adjustment method. Again, this rule of thumb is for drysuit undergarments and works well in practice. This past winter I added some folded pads of fleece over my chest area and simply took the material, folded and balled it up and estimated its displacement would be about a half gallon and would require about an additonal 4 pounds. That was just about right. For a "ROUGH" rule of thumb, where's the problem with physics? Remember, we're talking about drysuits where the insulation isn't significantly compressed at depth. I could be missing something, but I just don't understand your point. I should have clarified that I only use this method of estimating weight needed when FIRST trying a substantially different set or combination of undergarments, not for routine tweaking or fine-tuning. An example is when I first combined a new Weezle Extreme Plus with booties and wool socks, an additional ice cap hood under my regular hood, plus dry gloves with doubled liners. Previously, I was using layers of Polartec, one hood, neoprene mitts, fleece socks. By using my rough rule of thumb, I came up with a good idea what weight would be adequate and subsequent in-water tweaking was minimal to achieve a good weighting. In fact, that tweaking was done at the end of the first dive with a near-empty tank, so it was really quite accurate. > > > How many Cold Water diver you know calibrate their "proper weight" > > > (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How [quoted text clipped - 5 lines] > See, you're guessing, even for YOURSELF, judging from what you said > about how you estimate your own needed lead. Of course, I'm guessing about the other divers, but not for my own weighting. I just didn't express my self very well when talking about when I use my rough estimate. My log of temps/insulation/weighting combinations has entries for "minimum weighting" which I've determined after various dives with an empty tank by removing weight until just barely able to submerge with all air exhausted from the drysuit. > > Very few of > > us are concerned about how little weight somebody else has on or if > > they've optimized their weighting. > > Or their own. Ouch! Not true. They just give it less importance. > That's where WARM WATER WIMPS are much more "proper weight" oriented > because of the ease and freedom to DIVE WELL, without all the cold [quoted text clipped - 3 lines] > CONSUMPTION EFFICIENCY. That is one reason I can dive longer on > one tank of air than most. Air wasting through excessive adjustments for buoyancy is the primary issue, right? The secondary issue is that buoyancy control becomes difficult, but that's only when the overweighting is significant, I would say. That's why I think the "purists" over-emphasize this issue, at least when talking about a goal of being within two pounds of minimum weighting. And the seeking the ideal weighting is really most useful with tropical gear and conditions, rather than the cases of compression of thicker wetsuits at depth or drysuit undergarments needing less squeeze to be warmer. Both of those cases tolerate the less than ideal weighting without a significant problem. Just starting a dive with a full tank creates less than ideal weighting for much of the dive, despite claims of some that managing breathing can overcome the excess. > I was so fined tuned that I could tell the difference in the salinity > of the water between the Atlantic (Bahamas) and the Caribbean! > I have custom-made 1/4 lb pieces of lead that inserts into my > weightbelt. :-) Of course I had many 1 lb pieces too. In the tropics, it's probably possible to fine-tune weighting to this degree, that is, unless one had a gassy food for breakfast! 8^) > I think a diver SHOULD be properly calibrated to within a couple of > lbs. of the "proper weight". Most divers DON'T KNOW what that > number is, period -- or how to calibrate it! > > With a drysuit, which I use all year, proper amount of lead for me > > varies, as I'll change the amount of my insulation to match temp and [quoted text clipped - 4 lines] > > in warmth for the next dive. Of course, the trade-off is slightly more > > wasted air from adjusting for buoyancy changes during the dive. The next line really defines the parameters of improper weighting. > I never quibble about any "couple of pounds" by anyone. It's the > UNNEEDED 5, 10, or 20 lbs that are so commonly practiced by cold water > divers that I crusade against. Hear! Hear! Especially when that occurs in the tropics, as you originally mentioned. Overweighting makes a proportionately greater impact if the ideal "proper' weighting should have been 10 lbs to start with, versus an ideal of 30 lbs in cold water. Totally with you on this one. > > I make the weighting adjustments from experience of trial and error, > > occasionally referring to a log of what worked well to keep me warm [quoted text clipped - 11 lines] > the amount of insulation) there IS a "proper weight" that CAN be > properly calibrated. This is what I'm talking about. A "proper weight" for what purpose? DUI's manual states a goal of "minimal air" in the drysuit. Others have a similar standard. There's a point to the standard, for sure, for the reasons we've discussed already. So, I add 4 lbs to the minimum and find it significantly warmer. Of course, my insulation works better with a little more loft in it. Maybe thinsulate resists crushing better. I just bridle at these notions of absolutes. > It's the inadquacy of TRAINING agencies, which produced poorly trained > Instructors, who in turn mis-taught proper weighting and buoyancy [quoted text clipped - 18 lines] > don't mind being called a "purist" if you don't attach all the > untrue and derogatory implications in what you wrote! :-) Were the derogatory implications simply that I didn't value the goals of the purists? Did I mistate their case? Or misunderstand it? > My LYCRA suit has NO COMPRESSION whether I am at 15 fsw or 199 fsw > where I frequently visit. :) My 1.5 mil titanium was adequate [quoted text clipped - 4 lines] > The needed AIR in the BC is mostly to compensate for the 5 lbs > of extra weight of the AIR in the tank at the beginning of the dive! Agreed. A tropical scenario. A 7mm wetsuit's surface buoyancy compared to a 3mm reduces the validity of the concern about ideal weighting to some extent because of proportionality. A drysuit is different as I've beaten to death above. > > I think the purists' love of minimal weighting is best justified in > > warm water conditions which require minimimal thermal protection. Then > > the positive benefits would be pretty consistent. > It's perfectly justified in diving with any equipment, in any cold > water, [quoted text clipped - 3 lines] > > That's the bottom line. We apparently disagree as to whether it's EQUALLY important in those three scenarios where the minimum weighting is so different in magnitude and when compression or warmth are factored in. We also disagree in HOW important it is. That may be the "purist" distinction, which escapes me. Dave C > > > > BUOYANCY control is EVERYTHING in diving -- except it's a skill > > > > seldom acquired by the Cold-Water trained divers. > Snip > > > I beg to differ, Bob. We had one of the few meaty discussions I've had in rec.scuba.* for some time. Actually what I had said had been said by me (and in the ancient archives at least a decade ago). Since we had more agreements in the ESSENTIALS of weighting and buoyancy, I'll cut this short and provide mainly some clarifications for issues you didn't catch or misunderstood. > > Proper weighting can ONLY be calibrated, carefully, IN WATER, by > > a diver who knows HOW. I maintain this position, and in spite of you unfounded (I'll explain) "rule of thumb", you did indicate that you knew how to calibrate yourself near the end of the dive. > We're in agreement here, but I'm suggesting the optimum weighting isn't > all that important. Wasted air is the primary issue. Being able to > react quickly enough with breath control or power inflator is the other > issue. 5 lbs excess weight shouldn't even present much of a problem > except in shallow water for less experienced divers. "A 5 lb excess weight here, and a 5 lb there, and soon you'll talking about a REAL weighty problem" -- to paraphrase an old Dirkson saying about a billion here, and a billion there, you'll be soon taking about real money! First you have the extra 5 lbs of AIR (at the beginning of a dive), add 5 lbs unneeded weight, that makes 10. When said diver is wearing a 7 mil wetsuit in Coz, the compression at 80 fsw probably mean another 10 lbs or more. That's how a cold water diver was accelerating in his DESCENT when I had to act fast to pull him by the tank because the DM wasn't close enough. > > > I have a quick rule of thumb for ROUGHLY estimating weighting required > > > by undergarments is to put them in a plastic bag and ball them up with [quoted text clipped - 6 lines] > > All air out of the BC) when you're doing your safety stop at 15 fsw > > with 500 psi. > For a "ROUGH" rule of thumb, where's the problem with physics? The physics is Archimedes principle. So, how do you estimate the COLUME of the displacement of your wadded plastic bag that is partially submerged? (In cu.ft??) You can't! And if you're off by as little as 20% of the volume, you're off by more than 12 lbs according to Mr. Archimedes! > > Ultra trim trim plus minimal and proper weighting improves AIR > > CONSUMPTION EFFICIENCY. That is one reason I can dive longer on > > one tank of air than most. > > Air wasting through excessive adjustments for buoyancy is the primary > issue, right? Only for the grossly overweighted. The extra drag of the bulging airbag, and the unnecessary excess baggage of lead all add to the excess use of air for BREATHING to accomplish the same task of a diver with minimum trim and minimal lead. My Explorer Pro BC weighs merely THREE lbs (dry), but it has a MAX lift of only 16 lbs, fully inflated. Even the smallest BC for women now have about 40 lbs of lift! That's what my other BC has, and it weighs about 9 lbs dry. Diving in currents in Cozumel, you can REALLY tell the difference in the DRAG of these BCs alone, even without the excess weight. When divers are accustomed to having monkeys on their back, they don't realize how much better thay can dive without those monkeys. :-) > Just starting a dive with a full tank creates less than ideal weighting > for much of the dive, despite claims of some that managing breathing > can overcome the excess. You got that wrong. The excess 5 lbs is NECESSARY to be properly weighted so that WITHOUT those 5 lbs or air near the end of a dive the diver can remain neutrally buoyant with no air in the BC. There is nothing wrong with putting air in the BC at the beginning of a dive to compensate for those 5 lbs of air, at depth. Only Lee Bell "claimed" he could manage by breath control alone throughout the dive. Not many bad divers are as ignorant as Lee: http://tinyurl.com/dx2l6 > > BUt within EACH equipment (which includes the thickness of suit or > > the amount of insulation) there IS a "proper weight" that CAN be > > properly calibrated. > > This is what I'm talking about. A "proper weight" for what purpose? Good buoyancy control. Minimal diving effort in proper trim. > > It's the inadquacy of TRAINING agencies, which produced poorly trained > > Instructors, who in turn mis-taught proper weighting and buoyancy [quoted text clipped - 21 lines] > Were the derogatory implications simply that I didn't value the goals > of the purists? Did I mistate their case? Or misunderstand it? A little bit of each. You seem to portray the "purist" as one who would rather dive uncomfortably cold than add warmth and weight. In your paragraph about "benefit is reduced at depth ..." has nothing to do with a "purist's" notion of proper weighting. > > The needed AIR in the BC is mostly to compensate for the 5 lbs > > of extra weight of the AIR in the tank at the beginning of the dive! > > Agreed. A tropical scenario. In ANY scenario. In freezing water, you need EXACTLY the same amount of AIR to compensate for the weight of the air in the tank. You simply need more air for the wetsuit compression effect. . > > > I think the purists' love of minimal weighting is best justified in > > > warm water conditions which require minimimal thermal protection. Then > > > the positive benefits would be pretty consistent. I think you're still missing the point. The "minimal weighting" for a 7mil wetsuit diver is the minimal weighting of a lycra suit diver PLUS what it minimally takes to enable the diver to DESCEND, initially. > We apparently disagree as to whether it's EQUALLY important in those > three scenarios where the minimum weighting is so different in > magnitude and when compression or warmth are factored in. You are still hung up on the point about "minimal". The "minimum weighting" IS very different in magnitude, depending on the suit, diver, and diving. So, 6 lbs may be minimal for me diving warm; 15 lbs may be minimal for me diving very cold; and 25 lbs may be minimal for YOU diving your drysuit comfortably. But each is MINIMAL. Nobody ever said 20 lbs or some arbitrary number is too much. Well, I did say the diver wearing 75 lbs of lead diving in Cozumel was using too much weight because I didn't see anyone pumping helium into his blimp looking body. ;-) > We also disagree in HOW important it is. That may be the "purist" > distinction, which escapes me. > > Dave C I hope this follow-up clarified most of those issues. If not, then we'll just have to leave it the way it is, and let readers decide for themselves what each of us meant, and/or makes more sense. -- Bob. A couple of corrections of careless statements and typos. :-) > > > > > BUOYANCY control is EVERYTHING in diving -- except it's a skill > > > > > seldom acquired by the Cold-Water trained divers. [quoted text clipped - 52 lines] > by as little as 20% of the volume, you're off by more than 12 lbs > according to Mr. Archimedes! The "COLUME" was "VOLUME" of course. And I meant to say if you are off by 2/10 of a cu ft (not 20%) you're off by 12 lbs. The point was that it is virtually impossible to judge the VOLUME of displacement accurately. > > > Ultra trim trim plus minimal and proper weighting improves AIR > > > CONSUMPTION EFFICIENCY. That is one reason I can dive longer on [quoted text clipped - 120 lines] > > -- Bob. > > > > > BUOYANCY control is EVERYTHING in diving -- except it's a skill > > > > > seldom acquired by the Cold-Water trained divers. [quoted text clipped - 3 lines] > We had one of the few meaty discussions I've had in rec.scuba.* for > some time. It was good for me, too. Cigarette, Bob? 8^) > Since we had more agreements in the ESSENTIALS of weighting and > buoyancy, I'll cut this short and provide mainly some clarifications > for issues you didn't catch or misunderstood. SNIP > > > > I have a quick rule of thumb for ROUGHLY estimating weighting required > > > > by undergarments is to put them in a plastic bag and ball them up with [quoted text clipped - 14 lines] > by as little as 20% of the volume, you're off by more than 12 lbs > according to Mr. Archimedes! For this rough estimate of weighting, one can estimate the volume of water that _will_ be displaced by the drysuit undergarments by a number of methods. Measuring the actual displacement IN WATER isn't necessary for such a rough estimate, if that's what you thought I was doing. Again, let me emphasize that this is a ROUGH estimate. How rough? Might be plus or minus 10%, but it saves time and effort. So, Rube Goldberg here balls up the undergarments in a plastic bag, presses a little air out of the bag (to simulate the supposed "4 psi" experienced in actual drysuit use), and measures the volume, calculates the weight of displaced water. Your choice: make it a rough sphere, measure the circumference and work from there (what was it for volume of a sphere, 4/3 times Pi times the cube of the radius? I forget). Or, take a 5-gallon sheetrock mud pail with nice cylindrical shape and shove the bag of undergarments in the pail with slight compression and estimate the number of gallons occupied. You know the weight conversion from there. Why compress the undergarments to simulate 4 psi compression? Well, that's the reported typical pressure of the experts' recommended "proper" squeeze of the drysuit. That's because 4.5 psi is probably when your nuts pop! Goddam purists! I use a little less than proper compression, naturally. 8^) Dave C > > > > > > BUOYANCY control is EVERYTHING in diving -- except it's a skill > > > > > > seldom acquired by the Cold-Water trained divers. [quoted text clipped - 7 lines] > > 8^) No thanks. Gave it up cold turkey in August 1992, NOT for health reasons, but getting damned tired of the anti-smoking zealots. :-) My air consumption rate got a little WORSE after I quit. <G> > > Since we had more agreements in the ESSENTIALS of weighting and > > buoyancy, I'll cut this short and provide mainly some clarifications [quoted text clipped - 19 lines] > > by as little as 20% of the volume, you're off by more than 12 lbs > > according to Mr. Archimedes! Note my key objection to your rough estimate was the "wadded plastic bag partially submerged". > For this rough estimate of weighting, one can estimate the volume of > water that _will_ be displaced by the drysuit undergarments by a number > of methods. You didn't say that before! :-) > Measuring the actual displacement IN WATER isn't necessary for such a > rough estimate, if that's what you thought I was doing. Yes! Archimedes required you to measure the DISPLACEMENT in water! > Again, let me emphasize that this is a ROUGH estimate. How rough? Might > be plus or minus 10%, but it saves time and effort. That wasn't the problem. It was HOW you can get that close, even though 10% is hardly negligible. :) > So, Rube Goldberg here balls up the undergarments in a plastic bag, > presses a little air out of the bag (to simulate the supposed "4 psi" > experienced in actual drysuit use), and measures the volume, calculates > the weight of displaced water. Wait! You haven't determined how much water it displaced it YET. The volume of the wadded plastic bag is immaterial. It doesn't matter if it's 1 cu. ft. and 1 cu ft of water would weigh about 62.5 lbs. :-) If you have ever taken a plastic bottle underwater, you'll realize how SHALLOW you need to go before it is crushed by the pressure! You can't measure the volume at the surface and pretend it's the displaced volume as soon as you jump into the water. For a ROUGH estimate, you have to put Boyle and Archimedes as buddies to work together! > Your choice: make it a rough sphere, measure the circumference and work > from there (what was it for volume of a sphere, 4/3 times Pi times the > cube of the radius? I forget). You got the volume formula right, but see my preceding paragraph! > Or, take a 5-gallon sheetrock mud pail with nice cylindrical shape and > shove the bag of undergarments in the pail with slight compression and > estimate the number of gallons occupied. You know the weight conversion > from there. You are getting WARM, but still not close. Finally, the volume of the drysuit MAY or MAY NOT have much relevance to the amount of positive buoyancy cause by the AIR trapped inside the suit or its insulation garments. For the Viking drysuit I used, its VOLUME was quite large (the way you measure it), but I could dive with it in the pool, with no insulating garment, with 10 lbs of lead, because I could dump nearly all of the air between the suit and my body. For insulating garments, you'll have to get Boyle to help. > Why compress the undergarments to simulate 4 psi compression? 4 psi? :-) In your bath? > Well, that's the reported typical pressure of the experts' recommended > "proper" squeeze of the drysuit. Yeah, beware of the physics-deficient 'experts'. LOL!!! > That's because 4.5 psi is probably when your nuts pop! Goddam purists! Really now? At 100 feet, the water pressure is 59.25 pounds per square inch (psi), I must have pretty tough nuts because I didn't even FEEL any cracking pressure when I was diving down to almost 300 feet. :-) > I use a little less than proper compression, naturally. 8^) > > Dave C If I WERE Popeye (the rs one), I probably would say you're a pussy. :-) But I do suggest you study your PHYSICS a little bit more carefully, before misapplying it on your nuts. <WG> -- Bob. > Note my key objection to your rough estimate was the "wadded plastic > bag partially submerged". Okay, now I'm befuddled and don't remember saying anything like that. Rather than look through the crap I wrote, let me see if I can express myself better. > > For this rough estimate of weighting, one can estimate the volume of > > water that _will_ be displaced by the drysuit undergarments by a number > > of methods. > > You didn't say that before! :-) I probably left out some key antecedents to avoid belaboring the issue. I know better now. Thanks for the heads-up. 8^) You sure this whole thing wasn't a troll? I'm beginning to feel like I've been dragged endlessly along the surface of the pond with my eyes bulging out of my head. You're not messing with me now, are ya, Bob? 8^) > > Measuring the actual displacement IN WATER isn't necessary for such a > > rough estimate, if that's what you thought I was doing. > > Yes! Archimedes required you to measure the DISPLACEMENT in water! When drysuit diving, I succumb to convention and almost EQUALIZE the pressure in my drysuit, so the 4 psi refers to the difference of ambient pressure minus interior suit pressure, I believe. I should have been more clear. So, at depth, the undergarments are barely compressed by the outer shell. That's true for any depth, if the pressure difference is maintained. The volume of water they displace can be estimated by... STOP ME BEFORE I SAY IT AGAIN! You know the rest. Can we agree the air layer created by the undergarments is the primary positive buoyancy that we're trying neutralize with weight? And that it's volume remains nearly constant throughout the dive? My ROUGH rule of thumb, however inartfully expressed, is about estimating the volume of that layer to get an initial weighting prior to the dive, which would be followed by fine-tuning in-water. > > Again, let me emphasize that this is a ROUGH estimate. How rough? Might > > be plus or minus 10%, but it saves time and effort. > > That wasn't the problem. It was HOW you can get that close, even > though > 10% is hardly negligible. :) It's ROUGH and soon to be fine-tuned in the water. Does the near-equalization of interior suit pressure address the "problem" you mention? Please describe the problem, because I'm not seeing it. Or is my measurement/approximation method in question? > > So, Rube Goldberg here balls up the undergarments in a plastic bag, > > presses a little air out of the bag (to simulate the supposed "4 psi" [quoted text clipped - 5 lines] > matter if it's 1 cu. ft. and 1 cu ft of water would weigh about > 62.5 lbs. :-) The estimated volume of the wadded up insulation in the plastic bag is very close to the volume of water it will displace when it creates a layer of air over the diver's body in the drysuit. That volume will remain nearly constant throughout the dive as the diver equalizes or nearly equalizes the air in the drysuit. > > Or, take a 5-gallon sheetrock mud pail with nice cylindrical shape and > > shove the bag of undergarments in the pail with slight compression and > > estimate the number of gallons occupied. You know the weight conversion > > from there. > > You are getting WARM, but still not close. I need more elaboration of that statement. I don't understand what you mean. Well, I know you're close to a forehead-slapping moment, but suppose the undergarments occupy about the equivalent volume of 4 gallons (4/5 the height of the aforementioned high-tech measuring pail). Those undergarments, under only slight differential compression (4 psi supposedly after nearly equilizing), will displace about the same amount of water during the dive. That volume of water displaced won't change much at different depths because one continues to add air to the suit to avoid squeeze (and maintain buoyancy for those of us who only use the bcd for back-up). > Finally, the volume of the drysuit MAY or MAY NOT have much relevance > to the amount of positive buoyancy cause by the AIR trapped inside > the suit or its insulation garments. It's the volume of the buoyant layer or air created by the insulation in the drysuit that we're talking about, right? Not the volume of the drysuit. Also, the air trapped in the undergarments can migrate and escape, of course, which is the basis for the maneuvers designed to counter a feet-first out-of-control buoyant ascent. > For the Viking drysuit I used, its VOLUME was quite large (the way > you measure it), but I could dive with it in the pool, with no > insulating garment, with 10 lbs of lead, because I could dump nearly > all of the air between the suit and my body. Bob, I never talked about measuring the volume of the drysuit, just the volume occupied by the insulation which would create a layer of air. > For insulating garments, you'll have to get Boyle to help. > > > Why compress the undergarments to simulate 4 psi compression? > > 4 psi? :-) In your bath? I should have specified that this is the differential pressure. > > Well, that's the reported typical pressure of the experts' recommended > > "proper" squeeze of the drysuit. > > Yeah, beware of the physics-deficient 'experts'. LOL!!! > > > > That's because 4.5 psi is probably when your nuts pop! Goddam purists! > Really now? A DIFFERENTIAL pressure of 4 psi will squeeze that suit onto you pretty well. I like it a little looser. > At 100 feet, the water pressure is 59.25 pounds per square inch (psi), > I must have pretty tough nuts because I didn't even FEEL any cracking > pressure when I was diving down to almost 300 feet. :-) Are you talking about a drysuit dive? If so, you've just made the case that the air in the suit is equalized. If it was a wetsuit dive, you know that there's no squeeze on your body's solid or liquid masses, just on gaseous areas. And certainly the wetsuit's compression doesn't make it squeeze the person in it. What was your point about the 300 foot dive and water pressure? Did your palm come up and slap your forehead yet? (Listening carefully.) If not, you may need to explain more to me because I'm not following you. 8^) Dave C > > Note my key objection to your rough estimate was the "wadded plastic > > bag partially submerged". [quoted text clipped - 5 lines] > I probably left out some key antecedents to avoid belaboring the issue. > I know better now. Thanks for the heads-up. 8^) No problem. I was just trying to make sure I know you know what you mean, in a slippery subject in which many fell -- like Nick Simicich thought he needed 45 lbs of lead in his 1/4" wetsuit in Coz; and his pal Hugh Huntzinger thought in-water calibration was "common sense", little did he realize how FEW divers have an "common sense" that's worth two cents. :-) At this point, I know that you know that we know that in-water calibration is the only CORRECT and ACCURATE way of needed-lead calibration, I am satisfied to leave it at that, lest the rest of the readership gets tripped up in some minor technicalities. > > Yes! Archimedes required you to measure the DISPLACEMENT in water! That was just one of those technicalities. > It's ROUGH and soon to be fine-tuned in the water. That's a VERY important point. Based on my first hand experience with many divers, it is a FACT that many of them never fine-tuned their weight requirements, and unaware that they were overweighted by 5 or more lbs, unnecessarily. > > 4 psi? :-) In your bath? That was in part a joke to your statement below, and in part a reminder that it's known that embolism CAN occur at small differentials. > > > That's because 4.5 psi is probably when your nuts pop! Goddam purists! I still think your nuts are a bit too sensitive, don't you? :-) > What was your point about the 300 foot dive and water pressure? That my nuts didn't pop at 150 psi pressure? 8^) > 8^) > > Dave C I think we had a good enough discussion on this topic. Let's leave it at that, and not spoil the MAIN lessons on nits and nuts. -- Bob. > > > Note my key objection to your rough estimate was the "wadded plastic > > > bag partially submerged". [quoted text clipped - 5 lines] > > I probably left out some key antecedents to avoid belaboring the issue. > > I know better now. Thanks for the heads-up. 8^) I said that with tongue-in-cheek, Bob, to provide you an opportunity to amend your misquote and sort out the miscommunication. It's a bit frustrating that you didn't, but I tried my best. We just didn't seem to be able to pin down whether we had a MUTUAL understanding of how drysuit undergarments displace water with constant near-equalizing of interior suit pressure. And that a useful ROUGH estimate of that displacement can be made very easily. > No problem. I was just trying to make sure I know you know what you > mean, in a slippery subject in which many fell -- SNIPPED the unnecessary disparaging comments about other posters; just not my style, sorry, Bob. > At this point, I know that you know that we know that in-water > calibration is the only CORRECT and ACCURATE way of needed-lead > calibration, I am satisfied to leave it at that, lest the rest of > the readership gets tripped up in some minor technicalities. This was your side issue that departed from the discussion of a useful method of making a ROUGH estimate for the weight required by different drysuit undergarments. I give readers in this group more credit for being able to understand the topic discussed and not get "tripped up". > > > Yes! Archimedes required you to measure the DISPLACEMENT in water! > > That was just one of those technicalities. Just not applicable, in this case, Bob. We apparently couldn't get back on track. > > It's ROUGH and soon to be fine-tuned in the water. > > That's a VERY important point. Based on my first hand experience > with many divers, it is a FACT that many of them never fine-tuned > their weight requirements, and unaware that they were overweighted > by 5 or more lbs, unnecessarily. I made that point about needing in-water fine-tuning in my original statement on the topic, so long ago it seems like a bad dream. I just didn't accompany the point with any condescending fanfare. I think I mentioned the initial estimate was "ROUGH" a few times, too. Can you say... "nauseating frequency"? 8^) My original point was not to provide a primer in weighting, just a very specific useful rule of thumb related to drysuit diving. It was pretty clear. > > > 4 psi? :-) In your bath? > > That was in part a joke to your statement below, and in part a > reminder that it's known that embolism CAN occur at small > differentials. The original context was completely different. You've brought up another side issue... I'm getting dizzy... SNIP > I think we had a good enough discussion on this topic. Let's leave it > at that, and not spoil the MAIN lessons on nits and nuts. > > -- Bob. No doubt "as good as it gets", to quote the movie title, since it mostly involved repeating and clarifying, probably unnecessarily, as I think you would agree. Maybe we can do better next time to actually hear and understand what the other is saying. Ya know, it was beginning to feel like I was forced to use Scrabble letters to spell out what I was saying and to rephrase and clarify what you were trying to say... or maybe what you were trying not to say. When I tried to get you to clarify and discuss your own statements it seemed like the board kept getting bumped! Was that intentional, Bob? We can both be honest, right? 8^) Oh, and I certainly don't view my opinions as "lessons", but it's nice of you to say so! J-8 O-1 K-5 E-1 Bob, put me down for 15 points, please. 8^) Dave C > > > > Note my key objection to your rough estimate was the "wadded plastic > > > > bag partially submerged". [quoted text clipped - 9 lines] > amend your misquote and sort out the miscommunication. It's a bit > frustrating that you didn't, but I tried my best. I was doing my best to let you off the hook, and concentrate on our AGREEMENTS that the correcting calibration can ONLY be done in water, but you chose to keep harping on your ROUGH estimate you had already withdrawn as the first approximation. I think it's counterproductive to carry on this conversation. Let's let the READERS re-read the thread. > SNIPPED the unnecessary disparaging comments about other posters; just > not my style, sorry, Bob. If was necessary, to point out how certain INSTRUCTORS are erroneous and completely off base on the matter of weight calibration. So, your style is to sweep such under the rug? > > > > Yes! Archimedes required you to measure the DISPLACEMENT in water! > > > > That was just one of those technicalities. > > Just not applicable, in this case, Bob. We apparently couldn't get back > on track. Then I have to take back what I said about your understanding of weight calibration, because if you don't understand Archimede's Principle and how it relates to buoyancy, then you're back to your fantasy of the floating bucket. > > > It's ROUGH and soon to be fine-tuned in the water. > > > > That's a VERY important point. Based on my first hand experience > > with many divers, it is a FACT that many of them never fine-tuned > > their weight requirements, and unaware that they were overweighted > > by 5 or more lbs, unnecessarily. I gave you the credit you didn't deserve, in retrospect. > I made that point about needing in-water fine-tuning in my original > statement on the topic, so long ago it seems like a bad dream. You have now revealed that you didn't really mean what you said about fine-tuning. Else why do you keep harping back on your ROUGH estimate which was inappropriate and NOT used by you. > I think I mentioned the initial estimate was "ROUGH" a few times, too. > Can you say... "nauseating frequency"? 8^) Smiley notwithstanding ... YES, about YOUR pointless rehash. > SNIP > [quoted text clipped - 6 lines] > mostly involved repeating and clarifying, probably unnecessarily, as I > think you would agree. I would have agreed then. Not now. But I don't see any point in going any further. If you couldn't accept an intended compliment and statement of mutual agreement, and have to come back to CANCEL the source of the compliment, it's best to leave it as is. > Ya know, it was beginning to feel like I was forced to use Scrabble > letters to spell out what I was saying and to rephrase and clarify what > you were trying to say... or maybe what you were trying not to say. There are plenty you can find in the archives of what I had said BEFORE 1994 about buoyancy and weight calibration -- no different from what I said today. They are the PRINCIPLES that debunk what Instructors and many divers did a decade ago, and many of them continue to do so. So you had almost 700 dives, mostly in cold water. I've had that many dives, in cold AND in warm water, a decade ago, and quadrupled it since, and observed THOUSANDS more divers than you did today, even back in the early 1990s. > Oh, and I certainly don't view my opinions as "lessons", but it's nice > of you to say so! [quoted text clipped - 4 lines] > > Dave C Your wishes granted. 15 points of demerit, for your effort this round. ;-) -- Bob. > > I said that with tongue-in-cheek, Bob, to provide you an opportunity to > > amend your misquote and sort out the miscommunication. It's a bit [quoted text clipped - 6 lines] > > I think it's counterproductive to carry on this conversation. It's been interesting. The last word will be yours. Dave C > > > I said that with tongue-in-cheek, Bob, to provide you an opportunity to > > > amend your misquote and sort out the miscommunication. It's a bit [quoted text clipped - 12 lines] > > Dave C No need. Redundancy is useful only for diving equipments, not words. :-) Your last word sufficed, till out next discussion of any of my many favoriate topics in scuba. :o) -- Bob. > > > Note my key objection to your rough estimate was the "wadded plastic > > > bag partially submerged". [quoted text clipped - 5 lines] > > I probably left out some key antecedents to avoid belaboring the issue. > > I know better now. Thanks for the heads-up. 8^) I said that with tongue-in-cheek, Bob, to provide you an opportunity to amend your misquote and sort out the miscommunication. It's a bit frustrating that you didn't, but I tried my best. We just didn't seem to be able to pin down whether we had a MUTUAL understanding of how drysuit undergarments displace water with constant near-equalizing of interior suit pressure. And that a useful ROUGH estimate of that displacement can be made very easily. > No problem. I was just trying to make sure I know you know what you > mean, in a slippery subject in which many fell -- SNIPPED the unnecessary disparaging comments about other posters; just not my style, sorry, Bob. > At this point, I know that you know that we know that in-water > calibration is the only CORRECT and ACCURATE way of needed-lead > calibration, I am satisfied to leave it at that, lest the rest of > the readership gets tripped up in some minor technicalities. This was your side issue that departed from the discussion of a useful method of making a ROUGH estimate for the weight required by different drysuit undergarments. I give readers in this group more credit for being able to understand the topic discussed and not get "tripped up". > > > Yes! Archimedes required you to measure the DISPLACEMENT in water! > > That was just one of those technicalities. Just not applicable, in this case, Bob. We apparently couldn't get back on track. > > It's ROUGH and soon to be fine-tuned in the water. > > That's a VERY important point. Based on my first hand experience > with many divers, it is a FACT that many of them never fine-tuned > their weight requirements, and unaware that they were overweighted > by 5 or more lbs, unnecessarily. I made that point about needing in-water fine-tuning in my original statement on the topic, so long ago it seems like a bad dream. I just didn't accompany the point with any condescending fanfare. I think I mentioned the initial estimate was "ROUGH" a few times, too. Can you say... "nauseating frequency"? 8^) My original point was not to provide a primer in weighting, just a very specific useful rule of thumb related to drysuit diving. It was pretty clear. > > > 4 psi? :-) In your bath? > > That was in part a joke to your statement below, and in part a > reminder that it's known that embolism CAN occur at small > differentials. The original context was completely different. You've brought up another side issue... I'm getting dizzy... SNIP > I think we had a good enough discussion on this topic. Let's leave it > at that, and not spoil the MAIN lessons on nits and nuts. > > -- Bob. No doubt "as good as it gets", to quote the movie title, since it mostly involved repeating and clarifying, probably unnecessarily, as I think you would agree. Maybe we can do better next time to actually hear and understand what the other is saying. Ya know, it was beginning to feel like I was forced to use Scrabble letters to spell out what I was saying and to rephrase and clarify what you were trying to say... or maybe what you were trying not to say. When I tried to get you to clarify and discuss your own statements it seemed like the board kept getting bumped! Was that intentional, Bob? We can both be honest, right? 8^) Oh, and I certainly don't view my opinions as "lessons", but it's nice of you to say so! J-8 O-1 K-5 E-1 Bob, put me down for 15 points, please. 8^) Dave C > > > Note my key objection to your rough estimate was the "wadded plastic > > > bag partially submerged". [quoted text clipped - 5 lines] > > I probably left out some key antecedents to avoid belaboring the issue. > > I know better now. Thanks for the heads-up. 8^) I said that with tongue-in-cheek, Bob, to provide you an opportunity to amend your misquote and sort out the miscommunication. It's a bit frustrating that you didn't, but I tried my best. We just didn't seem to be able to pin down whether we had a MUTUAL understanding of how drysuit undergarments displace water with constant near-equalizing of interior suit pressure. And that a useful ROUGH estimate of that displacement can be made very easily. > No problem. I was just trying to make sure I know you know what you > mean, in a slippery subject in which many fell -- SNIPPED the unnecessary disparaging comments about other posters; just not my style, sorry, Bob. > At this point, I know that you know that we know that in-water > calibration is the only CORRECT and ACCURATE way of needed-lead > calibration, I am satisfied to leave it at that, lest the rest of > the readership gets tripped up in some minor technicalities. This was your side issue that departed from the discussion of a useful method of making a ROUGH estimate for the weight required by different drysuit undergarments. I give readers in this group more credit for being able to understand the topic discussed and not get "tripped up". > > > Yes! Archimedes required you to measure the DISPLACEMENT in water! > > That was just one of those technicalities. Just not applicable, in this case, Bob. We apparently couldn't get back on track. > > It's ROUGH and soon to be fine-tuned in the water. > > That's a VERY important point. Based on my first hand experience > with many divers, it is a FACT that many of them never fine-tuned > their weight requirements, and unaware that they were overweighted > by 5 or more lbs, unnecessarily. I made that point about needing in-water fine-tuning in my original statement on the topic, so long ago it seems like a bad dream. I just didn't accompany the point with any condescending fanfare. I think I mentioned the initial estimate was "ROUGH" a few times, too. Can you say... "nauseating frequency"? 8^) My original point was not to provide a primer in weighting, just a very specific useful rule of thumb related to drysuit diving. It was pretty clear. > > > 4 psi? :-) In your bath? > > That was in part a joke to your statement below, and in part a > reminder that it's known that embolism CAN occur at small > differentials. The original context was completely different. You've brought up another side issue... I'm getting dizzy... SNIP > I think we had a good enough discussion on this topic. Let's leave it > at that, and not spoil the MAIN lessons on nits and nuts. > > -- Bob. No doubt "as good as it gets", to quote the movie title, since it mostly involved repeating and clarifying, probably unnecessarily, as I think you would agree. Maybe we can do better next time to actually hear and understand what the other is saying. Ya know, it was beginning to feel like I was forced to use Scrabble letters to spell out what I was saying and to rephrase and clarify what you were trying to say... or maybe what you were trying not to say. When I tried to get you to clarify and discuss your own statements it seemed like the board kept getting bumped! Was that intentional, Bob? We can both be honest, right? 8^) Oh, and I certainly don't view my opinions as "lessons", but it's nice of you to say so! J-8 O-1 K-5 E-1 Bob, put me down for 15 points, please. 8^) Dave C > 15 lbs is a remarkably low amount of lead, especially for a drysuit > worn by an averaged size male, even with a very thin undergarment, As I'm sure you've figured out, Bob is far smaller than the average man, and has a very thin skin. The only thing buoyant about him is an exceedingly overinflated ego compensation device.  SignatureSteve The above can be construed as personal opinion in the absence of a reasonable belief that it was intended as a statement of fact. If you want a reply to reach me, remove the SPAMTRAP from the address. > > 15 lbs is a remarkably low amount of lead, especially for a drysuit > > worn by an averaged size male, even with a very thin undergarment, > > As I'm sure you've figured out, Bob is far smaller than the average man, You can infer from this the depth of statistical ignorance of Steve, that he thinks one who weighed 190 lbs is "far smaller" than the average man. That's not even smaller than those Canuch sows Steve likes to date. > and has a very thin skin. Nobody who has a thin skin can survive a degenerate newsgroup like rec.scuba.*, with dysfunctional mental midgets replacing each other. I've seen them all, since 1989. An outlasted them all! > The only thing buoyant about him is an exceedingly overinflated ego > compensation device. A moron making an oxymoron statement. How can something buoyant COMPENSATE for overinflation? Steve has the intelligence of an "average" <adj.> Canadian moose, has an IQ far less than that of the "median" of a Canadian goose, but his IQ is right at the "mode" of the IQ of rec.scuba posters. Steve learned his statistics from the extinct-Professor Brannigan, both of whom had been exposed of their extreme ignorance years ago, and he still hasn't gotten over it. Changing his NAME didn't help. -- Bob. > -- > Steve [quoted text clipped - 3 lines] > > If you want a reply to reach me, remove the SPAMTRAP from the address. > I have a quick rule of thumb for ROUGHLY estimating weighting required > by undergarments is to put them in a plastic bag and ball them up with > a little compression and estimate the volume they will displace in the > water. An interesting and clearly effective ROM technique! Thanks. > Of course, in-water adjustment of weighting would be the last word. But of course...that's nothing more than common sense. -hh "Dick" <devil505@adelphia.net> pounded away at his keyboard resulting in: :While most of the excursions boast a 2 tank dive, my fear is that they will :chase us out of the water after 20 minutes per tank! So what if they do? You can choose to enjoy the 20 minutes you dove or complain about the 30 you didn't. I would choose the former. Dan Bracuk If we don't succeed, we run the risk of failure. > I am an experienced diver (over 20 years but just recently got certified) > who has never dove anywhere but New England. New England? I've heard some pretty good things about shore diving in or around the Cape Ann area. Any suggestions? >... I'm one of those "Mike Nelson/Sea Hunt" guys who has some > pretty old (but always serviced) equipment. I am using an old Sherwood > regulator (with no safe 2nd stage) & wonder if the cruise ship excursion > dives will even allow me to use this for their dives? The default equipment expectation these days is (1) regulator with octopus and pressure gage, (2) a timing device or dive computer, (3) Buoyancy Control Device (BC) & (4) Mask/Fins/Snorkle, and (5) weights and thermal protection as required. You know what you have, so you can run down through this checklist to see what's missing besides your "safe 2nd stage"...aka octopus. For the octopus, adding this to your existing Sherwood regulator system isn't that expensive, but if by finally picking up a C-Card you're thinking about diving more (or more dive travel), it may be time to upgrade your ancient Sherwood...its worth thinking about, at least. BTW, its safe to generalize that a chartered dive down south in a generic warmwater destination provides more than just the boat ride: the "2 tank" dive trip will include two AL80's (yoke, not DIN) plus the operation will usually have weights for you as well, and often a loaner weightbelt too. (YMMV, but I always bring along my own weightbelt, so as to have a good metal buckle instead of a well-worn plastic one as found on most freebies.) Bottom line here is that you don't need to take along your own tanks or weights. Similarly, something else worth thinking about is that if you're only going to be getting a couple of dives in on this particular cruise, then there's also a decision to be made of if you personally think its worth schlepping all of your personal gear along if you're only going to use it but a few times: you may decide to choose to rent your regulator & BC rather than to drag your own along. Its been a long time since I've rented, but I'd SWAG it as probably a $50/day expense. > (I already plan on bringing my own mask, snorkel & fins) As a coldwater diver, your fins are probably open-heel and thus also require you be wearing your boots, so don't forget to bring them along. > Any other advise/experiences diving > on cruise ship excursions would be appreciated. (My local dive shop > recommended that I stick with these excursions as the boat won't sale > without me if the dive boat returns late!) Probably a reasonably good idea for the first cruise/dive, to get a hang of how they do everything. > While most of the excursions boast a 2 tank dive, my fear is that they > will chase us out of the water after 20 minutes per tank! Do generally expect that your dive will be "guided" ("herded"), so you won't necessarily have as much dive freedom as you're used to. OTOH, you can expect water visibility that's roughly 10x what you've been used to too...you can spread out :-) The dive duration is fairly likely to end up being based upon the cruise ship's schedule as well as the lowest common denominator skills of the group, which for cruise ship based customers probably isn't generally considered to be that great...you'll have your air hoovers as well as "bottom-crashers"...hopefully, you're neither of these...which will also be a consideration in dive site selection by the dive shop. In other words, while the warmwater coral reef experience will be something new & different for you, its fairly unlikely that they'll take you to the best spots, due to an unfortunately deserved concern for reef damage from an unknown group of divers. BTW, are you bringing along your own dive buddy, or are you expecting to get a "pickup buddy" at the destination? Hope this helps, -hh > > I am an experienced diver (over 20 years but just recently got certified) > > who has never dove anywhere but New England. > > New England? I've heard some pretty good things about shore diving in > or around the Cape Ann area. Any suggestions? Hugh, I'm sure Dick will have some good advice on diving Cape Ann, MA, but here are some links. I dive there often, so if you want more specifics about individual sites, feel free to email me at: dcalderbank AT cheshire DOT net Good shop: http://www.capeanndivers.com/ And their page describing specific dive sites: http://www.capeanndivers.com/findadivesite.htm HTH. Dave C > Hugh, I'm sure Dick will have some good advice on diving Cape Ann, MA, > but here are some links. [quoted text clipped - 9 lines] > > http://www.capeanndivers.com/findadivesite.htm Thanks, Dave. Our local dive club goes up to Cape Ann occasionally & I've partly not had the interest since IIRC they choose to do it as a dive/camping weekend. -hh Thanks for your reply hh......The farthest north I've dived is around Marblehead (a bit north of Boston) but I live in Plymouth so most of my diving has been on the south shore. There is a nice spot to dive on Marblehead Neck & many nice spots south of Boston.. Make sure you have/rent a full wetsuit with boots,gloves & hood! The waters around here never have great visibility but it is usually ok if you don't dive right after a storm. Most divers around here go after lobster (State license required) which is always fun! Probably the best thing to do for specific dive-site recommendations is to contact a few local dive stores. In Plymouth contact The Diver's Market at 508-746-3483. Dick >> I am an experienced diver (over 20 years but just recently got certified) >> who has never dove anywhere but New England. [quoted text clipped - 79 lines] > > -hh > Make sure you have/rent a full wetsuit with boots, gloves & hood! The same applies down here in NJ...offshore, the bottom temps are right around 50F right now. > Most divers around here go after lobster (State license required) > which is always fun! MA requires a lobster license even for hand collecting? How much does that cost? Somehow I suspect that a weekend license isn't available, either. -hh > I am an experienced diver (over 20 years but just recently got certified) > who has never dove anywhere but New England. Just this line alone, without the Mike Nelson bit, smells like a troll by a clueless New Joisey poster. What happened was that his troll in rec.scuba.equipments ran out of steam after a few days in July, and this Dickhead decided to try his same troll in rec.scuba.locations, on August 19, after Popeye told him, Popeye> You're going to die. :-) Dick had a DIFFERENT self-intro in rec.scuba.equipment (one I never read anymore, but found him via google, just to see what kind of NUT CASE this Dickhead is): > I am a 58 year old, experienced scuba diver (with over 20 years of diving > under my belt) who was hit by a car in 1989 & hasn't been diving since. I [quoted text clipped - 3 lines] > (Yes...I am one of those "Mike Nelson" of Sea Hunt guys that has plenty of > experience but never felt the need to get certified) Hit by a car in 1989 and hasn't been diving ... that's 17 of Dick's "experienced diver", NOT diving for 17 of his last 20 years -- he concealed THAT confession, to make his New, Improved "troll" Lack of warm water diving is the LEAST of your problems, Dick. I had him sized up to be a Clueless Newbie after his first line! Now it's confirmed by his confession to the equipment group. Go back to your alt.home.repair groups, Dickhead. I think Pops had you sized up just right: Popeye> You're going to die. All you have to do is to take your New Joisey outfit and your Mike Nelson knife to a warm water dive location, and dive solo. That'll do it! LOL You are ALREADY dead here. -- Bob. Listen Bobby (only men deserve to be called Bob) why don't you go back to the childish "Insult" newsgroups where you belong?!?! This will be my last post to you as life is way to short to have unnecessary run-ins with children like you..Grow up! >> I am an experienced diver (over 20 years but just recently got certi |
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