18 pound wing from scratch

[popolarbear]

Wow! been off this board for awhile.

ive got the same welder for other aplication. dont bother attempting to weld with rod. they also make attachment roller that would do similar final product as ultrasonic weld. if i was going to attempt with hot air welder id start with trying to find one of those attachments(not common).

but if being a scroung/customizer is the ultimate goal. i think id start with attempting this using flexible PVC glue used for pond building. use the flex PVC liner also used for pond building.
infact you got me thinking now. as ive been contemplating a custom BC, as none realy fit my type of diving short of no BC at all.

I would like to do two BCs.
one a modified addition to add to traditional BC to alter the flotation angle.

 

[popolarbear]

oh for those thinking about this. I would recomend start looking at liners made by tetra out of germany. they are green on one side and black on the other. most liners in the pond industry are rubber. these are PVC flexible. ive used these and like them as they are easy to repair using flexible pvc glue. even so this material will be somewhat more rigid than typical bc. will also be more puncture resistant. youd probably be able to stand on the bladder without issue.

im new to this subject. is there an overinflation relief valve on typical BC. also do most manufacturers just simply thread the inflation hose stuff on, or do they glue it on?
also what stops me from dissassembling a used BC for parts for this project.

you got me very interested. if i can find the BC parts ill do a project and post my findings.

 

[udtfire]

I see your from dc it figuars
there you redesign and put you life at risk fixing what is not broken and in trying to save a dollar youll spend ten. ill bet you work for the goverment lol

just ment in good fun

 

[Cave Diver]

20 mil PVC material, clear: $12/yard*1/2 yard = $6 (1 yard of material is 60 inches wide so can fit both “sides” of the bladder)
PVC welding rods: Qty 50 48” rods/$16 * 2 rods = $0.64 (2 rods because I’m planning for double welds)
Power inflator: $30
Power inflator corrugated hose: $6
Power inflator elbow: $9
Power inflator gasket: $1
Power inflator flange: $9
OPV: $12
OPV flange: $9
OPV Gasket: $1
800 Cordura Nylon: $12/yard* ½ yard=$6
Polyester thread: $2
Zip ties: 1000/$20 * 2 ties=$0.04

Total: ~$83 + Labor

I know you said you already had some of this stuff on hand from previous projects, but I'm curious on where you'd source some of this without that benefit. Specifically the Cordura and the 20 mil PVC.

 

[jhayes75]

This place is usually a good source for raw materials.

McMaster-Carr

I know you said you already had some of this stuff on hand from previous projects, but I'm curious on where you'd source some of this without that benefit. Specifically the Cordura and the 20 mil PVC.

 

[popolarbear]

saw this on another forum

on materials
Heat sealable taffetaCoated and Uncoated Nylons : Reflective Fabric : Polyester Fabrics : Seattlefabrics.com

 

[fjpatrum]

I know you said you already had some of this stuff on hand from previous projects, but I'm curious on where you'd source some of this without that benefit. Specifically the Cordura and the 20 mil PVC.

I usually buy my cordura from G-Street Fabrics, either online or local at a brick and mortar store. PVC I always buy online but I think G-Street carries it as well.

 

[fjpatrum]

Wow! been off this board for awhile.

ive got the same welder for other aplication. dont bother attempting to weld with rod. they also make attachment roller that would do similar final product as ultrasonic weld. if i was going to attempt with hot air welder id start with trying to find one of those attachments(not common).

but if being a scroung/customizer is the ultimate goal. i think id start with attempting this using flexible PVC glue used for pond building. use the flex PVC liner also used for pond building.
infact you got me thinking now. as ive been contemplating a custom BC, as none realy fit my type of diving short of no BC at all.

I would like to do two BCs.
one a modified addition to add to traditional BC to alter the flotation angle.

So far the glue doesn't hold well enough to the pressure of an inflated bladder, which is why I'm trying the welding. I may be able to get around this by "double welding" with the glue, like I am with the welding rods, but so far I'm not optimistic about it. Another solution would be to make the cover slightly undersized, as knowone suggested, and then you wouldn't put too much pressure on the glue welds. When I get back to this I'll get a little more practice with the rods and then perhaps I'll be more consistent than my original efforts. I'm slowly finding a technique that doesn't melt the PVC too badly and once I've got the technique perfected, this should be a clockwork exercise to finish a few different sized bladders. I have thought about trying the glue again just as another test piece.

To answer some of your other questions... most of the "parts I already had" came from used BCs, so it's perfectly feasible to do that. So far I've bought 4 or 5 used BCs specifically as parts hosts. Tank bands, pressure relief valves (yes they are on most BCs as you think) and inflator hoses come much cheaper on used BCs than buying them new. I've seen the relief valves just screwed in place with gaskets and I've seen them glued in place. I think some of them were glued in place to stop minor leaks, though, so I can't say for sure that was that way by design.

UDTfire: as I've clearly shown in my cost analysis, this isn't spending $10 to save $1 but I understand the jest. This is mostly because I'm an engineer through and through-- I build things. All kinds of things, from boats to planes to computers to houses to rock climbing and diving equipment. I like building and designing things, whether the available offerings are broken or not. There's nothing wrong with buying a wing from an established manufacturer. I suspect those that buy DSS equipment are very glad that Tobin decided to start making his own, though. Similarly I'm considering building aftermarket download cables for dive computers too. Not because it will save me money but because it will be fun to do and will serve a small niche of people like me who don't see a need to go out and buy new equipment all the time when the "obsolete" equipment is still working. PS: I don't work for the government but I do work for a defense contractor... getting paid by the government.