New to backplate and wing... Weight question

[Bklyncg]

I recently bought a new single BP/W 30lb lift . Aluminum 2lb plate, single 2in web harness.

I have about 100 dives using a jacket style BC and i usually use about 12LBS in saltwater with a 1mm skin. i'm a bigger guy 6'3 290lb (not fat)

i know the simple answer is to get in the water and do a weight check... i just looking for a baseline.

Should i start with the same 12lbs that i usually use with the bulky jacket? or should i start with a few lbs less to compensate for the 2lb of the aluminum plate.

As far as weight distribution, i have 4 trim pockets (2 ditch-able) i can add to the kit. i was thinking of 2 on the waist band and 2 on the upper cam band. does this seem like a good starting point.

I'm sure this question has been asked a bunch, i appreciate any advice however. thanks

 

[grantctobin]

I’d personally cut to 8 but you could weigh your BC in a tub if you’d like as well. Things like STA and moving from plastic cam bands to metal cam bands can increase added weight reduction. Worst case bring extra (e.g 10) and clip to downline/buoy/float/give to buddy during safety stop with min gas (~500psi)

 

[Bklyncg]

I’d personally cut to 8 but you could weigh your BC in a tub if you’d like as well. Things like STA and moving from plastic cam bands to metal cam bands can increase added weight reduction. Worst case bring extra (e.g 10) and clip to downline/buoy/float/give to buddy during safety stop with min gas (~500psi)

How exactly would i weigh the BC in the tub? thank you for the reply

 

[lowwall]

Since Al is such low density, that 2lbs equals around 1.2 pounds of negative buoyancy. However, you also get to take off the inherent buoyancy of your current BC, which could be several pounds.

I suspect you'll end up with 8 pounds, but If you can't do a proper check, take 10 pounds on your first dive and then see if you are heavy on your stop. If you have a cooperative buddy, you can hand him a 2 or 3 pounds and see what effect that has. Obviously discuss it on the way out.

I like your plan of splitting the weights between your upper cam band and waist band. I'd put 2 on each of the cam bands and a 3 or 2 and 1 on the waist for the first dive so it will make it easier to experiment. Once you get the weight dialed in, you can figure out the trim by getting horizontal, stopping all motion and seeing what happens.

 

[Bklyncg]

Thank you.. very helpful info.

Since Al is such low density, that 2lbs equals around 1.2 pounds of negative buoyancy. However, you also get to take off the inherent buoyancy of your current BC, which could be several pounds.

I suspect you'll end up with 8 pounds, but If you can't do a proper check, take 10 pounds on your first dive and then see if you are heavy on your stop. If you have a cooperative buddy, you can hand him a 2 or 3 pounds and see what effect that has. Obviously discuss it on the way out.

I like your plan of splitting the weights between your upper cam band and waist band. I'd put 2 on each of the cam bands and a 3 or 2 and 1 on the waist for the first dive so it will make it easier to experiment. Once you get the weight dialed in, you can figure out the trim by getting horizontal, stopping all motion and seeing what happens