Dialing in my weight with a Farmer John-tips please

[SPKelpDiver]

I was using a 7mm/5mm semi-dry in the first part of the winter with a 3mm non-hooded vest underneath with 26lbs and an AL 80. I don't know if it is the suit or what, but I am still cold, especially in my arms. So I am switching to my farmer john...its a 6.5mm (x2) on both peices and I am renting a steel 95 so I can keep up with my buddies bigger tank. I am not planning on wearing the 3mm vest, just a underskin to help the suite slip on. I was thinking about taking out 28lbs with the FJ 6.5mm and a steel 95. I am diving a little deeper than normal with this setup so I want some feedback so I feel better about this. Thanks.

 

[diverrex]

Witout looking up the specifics I'd say the steel 95 is about 6 lbs more negative than the alu 80. I doubt the farmer john requires 8 more lbs than the semidry, so it sounds like you'll be heavy. Why don't you do a weight check at the beginning to find out how much you need.

FWIW I dive a 7MM farmer john with a 3mm hooded vest and steel 100. I'm about 160 lbs and use 15 lbs of weight.

 

[ligersandtions]

There is really no good way to estimate it without doing a proper weight check. You have three options for a weight check (one of which is my preference, but I'll go through all of them).

Option 1: At the start of the dive, figure out what weight makes it so you're neutral at the surface....dump all the air from your wing and breathe from your regulator....on exhale, you should be below eye level, on inhale you should be above eye level, with a neutral breath you should be right about eye level. Then you'll need to add the weight of the air in your tank to your weight belt so that you are neutral at the END of the dive (very important for your weighting to be correct for the end of the dive so you can maintain your safety stop). In the case of diving a 95 cubic foot tank, you should add 7 pounds to your "neutral" weighting.

Option 2: At the end of your dive, get to a place with a sandy bottom (or somewhere you aren't hurting life and it's not hurting you....sand is good for this). Remove all the air from your wing, purge your tank down to less than 500 psi (if you're not there already), and remove weight until you find yourself neutral. At this point, you are weighted properly for your safety stop.

Option 3: At the end of your dive, on the surface, remove all the air from your wing and have ~500 psi in your tank. Remove weight until you are neutral (when you breathe off your regulator, you will be negative on exhalation, positive on inhalation, eye level with a neutral breath).


FWIW, if you plan to continue diving socal and want to do multiple dives a day and/or go fairly deep, your best bet is going to be a drysuit. I held out as long as I could, and I'm so glad I finally broke down and bought the drysuit. It really makes multiple dives a day or deep dives much more enjoyable....it also makes the surface intervals more enjoyable, and it's certainly nice to be able to take it off and be dry and ready to drive home.

 

[MaxBottomtime]

A 95 will be about nine pounds heavier than a full aluminum 80. You shouldn't need more weight. When using a diveskin under a wetsuit you are eliminating the space between the skin and wetsuit that your body warms. You will actually be colder with a diveskin under a wetsuit. Try putting plastic grocery bags or hair conditioner on your hands and feet to let the suit slide on and save the diveskin for warm water.

 

[ligersandtions]

BTW, an AL80 is +4.4 pounds empty, whereas a steel 95 is -1.2 pounds (Faber) or -3.3 pounds (PST) empty. This means you will be able to remove 5.6 to 7.7 pounds based on the tank alone.

However, I can't tell you how much you'll need to add with the new farmer john....you'll probably need to add less than you can remove (so you'll get a net removal of weight...). But, of course, it's better to be a bit negative than a bit positive, especially if you are flirting with NDL.

 

[SPKelpDiver]

Hey thanks for the advice, and I am kind of blown away to here that the underskin might actually make things worse, but it makes sense. I am going to go dry eventually, but I need the time to take a class on it, plus the money for the suite. By next winter (hopefully) I should be dry.

 

[MaxBottomtime]

Another recomendation, which is probably very unpopular here is to skip the class. Descend in the middle of the cove at Marineland into ten feet and you'll already know when to add air to your suit and when to purge. At first it's a nuisance but becomes second nature during the dive.

 

[FrankPro1]

You will actually be colder with a diveskin under a wetsuit. Try putting plastic grocery bags or hair conditioner on your hands and feet to let the suit slide on and save the diveskin for warm water.

You might be right Phil. KelpDiver is well built and has large muscular arms. Wearing the diveskin in conjunction with a tight semi-dry is probably preventing the pocket of water "that usually warms a wet-suit diver" from forming in his arms and thus is getting chilled. The semi dry was initially defective "had a huge internal tear in the crotch area" and that proned the purchase of a pinnacle undersuit and bioply dive skin. I am also using the pinnacle undersuit but not the bioply. Thus far I haven't had any problem with the cold.

Its also strange that SpKelpDiver was warmer with the cheap-o, bottom of the barrel front zipper BearSkin suit that they gave him to use while his Semi-dry was being repaired. "I am also using that same style suit and have been quite warm most of the time". It doesn't make much sense that a more expensive Semi-dry 7/5mm is not warmer then the basic 6.5mm front zipper wetsuit. Initially we were quite perplexed about this instance, until he found the tear in the crotch. Now he's still getting chilled even after repair. I'm sure it will be a giant relief for him and me if its something as simple as removing his bioply skin.

I know he probably won't try it for the next couple dives "were doing Long Point tomorrow and Casino Point on Tuesday" but maybe after that he'll have to experiment with it.

Thanks to you Phil and everyone else for helping my buddy out

 

[JMdiver]

Hi SP,

I dive a FJ with a al80, steel 72 & steel 120. I'm 220 5'11" ( I know I'm working on loosing wieght) & use 30#, 24# & 20# respectfully. No dive skin. Hope this helps.

John

 

[SPKelpDiver]

Yea it might be unpopular on the board, but it is very popular with my wallet. I have heard stories of uncontrolled feet first uncontrolled ascents, is this something to be worried about or does it hold about as much weight as the backinflate at the surface BS. That is my only concern with the drysuit, even though I have heard it is somewhat overblown.