Cheat Sheet

[SLATSY]

Hi all the more I get into diving the more I realise is to be learnt and more I forget, is there a cheat sheet as such with basic rules and formulas available an example would be if I go from a 5mm semi dry to a rashie what's weight diff or ally to steel tank , if u say went from fresh to salt what's a ratio of weight req these only couple of examples just thought I'll ask what's about of summarised key info

 

[FinnMom]

This is exactly what can be great about your logbook! Someone else's answers won't ever be such a great fit for you, but when you do try your 5mm suit with the 15L tank, make a note of what your proper weight belt weight was. It's nice too to see how cold /warm the water was an whether you were too cold, just great or too hot <= apoligies to Goldilocks
Note too how deep you noted a lake or quarry to be, sometimes's it's nice to be able to answer that question some 6-8 years later.

Find the answers/formulas/info you want and write them down in a form you understand. No one could ever do a better job of compiling exactly what you want.

 

[Doby45]

I could not agree more, your own logbook (if info is logged properly) will be the best info you can have.

I know in my 5mm full suit and with a single 80 tank that 12lb is perfect for me with my Express Tech BC. 4lbs on shoulders and 8 in waist pockets.
I know in my 5mm full suit and with a single HP100 tank that 4lbs is perfect for me with my Express Tech BC. 4lbs on shoulders for perfect trim.

I am about to purchase a drysuit and that will add another wrinkle, but with proper notes even that wrinkle will be ironed out.

Each time you dive a different configuration or a different environment or both, you make those notes so that you can go back to them. Then when you are on a magical dive trip somewhere and you need to figure out your weighting or trim you can glean that info from your logbook.

 

[sheeper]

+1 on keeping that logbook. the info about configurations is invaluable as you dive more and get more experience

 

[tbone1004]

unfortunately there is no cheat sheet.

is your 5mm semi-dry new? what brand is it? How many times has it been to 30m? Do you flood your suit before you dive, or do you try to stay dry?

Are your aliminum tanks luxfer or catalina? Are the steels PST, Faber, Worthington, etc etc? They are all different buoyancy specs

How large are you? The weight difference in fresh to salt is all about how much water you displace, not necessarily how much you weigh.

The only thing to do for ballast checks are to do proper weight checks and record them.

 

[SLATSY]

I agree logbooks can be valuable source for revision and self learning but what if faced with something new having starting points would be a great point to get dialled in quicker like if a general rule existed say for every mm that a wetsuit gets thicker you add x amount of ballast , just wanted to know what literature is around or if anyone has summised years of log book entry to rules that work for them or wants to share little secrets for any aspect

For example I found this

• Going from fresh water to salt? Multiply by 0.025 and add that amount.
  
  • Going from salt water to fresh water? Multiply the total by 0.025 and subtract that amount from your weight belt or integrated-weight BC.
    
    Not saying it's perfect for everyone everywhere but if it's a new experience gives a good starting point

 

[tbone1004]

it's a starting point, but it's not an accurate number because it is about displacement, not weight. You can't do anything about mm of wetsuits because there are a myriad of different neoprenes out there and the air:rubber ratio will determine how much positive buoyancy they have, as well as the sizing. One of my female buddies wears an XS, I wear an XXLT, and I have other buddies in king size wetsuits, can't make any generalizations. Proper weight checks take very little time, less than 5 minutes, and you are not changing equipment that regularly so just keep track.

 

[TMHeimer]

I don't use the log book. As tbone1004 said, just do a weight check with all your different variables. My list of weights is simple. I only use AL80 tanks and have 3 different thickness wetsuits. I know them by heart of course, but have the amounts written down. My "new" farmer john 7 mil meant adding 6 pounds more than I needed from the old piece of junk. So new weight check.

Yours may be more complicated, so a longer list. Of course this assumes you don't gain or lose 50 (or less?) pounds of body weight.

 

[Bob DBF]

I have a page in my log binder with weight for different gear configurations, along with other pages for handy facts I might want. Oh, wait a minute, that is a cheat sheet.


Bob

 

[Diver Dan 28]

Divebuddy.com has a bunch of useful calculators. I log my dives to reflect on when I'm not diving, also when the seasons change it give me a good starting point for each gear configuration.