nuttytoe:
I am thinking about buying a dive rite backplate. However, i can't decide between the ABS and the S/S. I will be doing mostly saltwater diving and also travel a lot. I like the ABS because it is light but does not have a lot of holes for attachments. The S/S is okay, but i would like to cut down the weight and some price too. Please advise.
Hoser, you don't select a plate based on whether or not it has holes in it, or which one travels better. In general, you don't select gear based on how it works
out of the water. You select gear based on what's going on
in the water - e.g. submerged. Your backplate is something that integrates with other components underwater, to provide you with a balanced rig that trims out nicely and allows you to dive effectively and efficiently.
Its about weighting your rig so that you achieve equilibrium at the end of your dive, with your tank(s) nearly empty, given the positive bouyancy provided by your wetsuit or drysuit/undergarment in concert with the negative bouyancy resulting from your tanks, regs, backplate, and the rest of your kit. Your body is like a lever, with the fulcrum somewhere between your sternum and your hips. A 6 lb plate, for example, takes 6 lbs off your hips and puts that weight flat against your back, where its more stable as well as closer to your center of gravity. A 12 lb plate does the same thing, it just displaces more weight. Which one you use depends on where your buoyancy is located, and where you need to put the weight correspondingly to adjust your trim.
Sometimes guys with heavy doubles use a plate which weighs zip with a belt holding between 6 and 12 lbs. This is because the weight of the tanks and regs is more than they need above the fulcrum, and they need to position some weight further down the lever in order to trim out when they hover motionless.
But if you use a plate that weighs zip, ('cause it travels well), with a lightweight tank like an aluminum 80, and a full 3 or 5 mm wetsuit, guess what? Standby to strap a 16 lb (or heavier) weightbelt on when you get where you're going. Can it be done? Sure. But it puts those pounds further down the lever - just above your hips. Will it allow you to float motionless either horizontal or with a slight head down fins up trim? Doubtful - unless you've determined this is what works for you
before you fly off to resortland. It's more likely going to trim you out feet down head up, so you'll rototil your way across the reef.
The trick with the stuff you buy is to realize that its all part of a system, and what you use on one place impacts all the other parts of the system elsewhere. If you don't realize this, you end up buying the wrong stuff (and then being unhappy with it).
See if you can't scrounge up a few different plates from your buddies, and go try them out with whatever other equipment you'll be traveling with. If the light plate works, then fine. But if you need a heavier plate to balance out your rig, then better to know that and let it be the basis of "which plate do I buy", rather than trying to make a decision based on how many holes it has in it or what its made of.
Regards,
Doc