Custom RCABS bladders

[virg]

Hi everyone,

I would appreciate hearing from anyone who can advise me on how to make a custom sized bladder or if it is possible to shorten existing bladder and sealing the end. Is it possible to do this using adhesives or heat? It needs to fit comfortably in the ballast compartment of a D&E WTC, 3". Any tips, hints or advise?

Thanks,

Virg

[tmsmalley]

Hi Virg -
I moved your

Hi Virg -
I moved your post over from the Forum Tips & Tricks to here. Dan Lewandowski, who posted a nice thread on his build of a Big Dave Seawolf WTC a few months ago, customizes neoprene blood pressure cuffs by cutting them to size and then sealing the edges with wetsuit cement.
http://s181686668.onlinehome.us/phpBB2/ ... highlight=
Crazy Ivan has used IV bags and heat seals them with a standard clothes iron.

[virg]

Thanks Tim, that's what I

Thanks Tim, that's what I needed to know. You're on the ball, as usual.

Thanks a bunch,

Virg

[tmsmalley]

You bet Virg. Dan gets

You bet Virg. Dan gets his wetsuit cement at the local scuba shop.

[danl]

Virg,
The BP cuff bag can

Virg,
The BP cuff bag can be cut and reglued with black neoprene cement.
Some hints from experience, not the best hints maybe, but at least you won't repeat my mistakes!
1. Plan the cut carefully, leaving material to form flaps for an overlap seal of the desired shape.
2. Don't do square corners - they make the bag blow up in a very contorted shape. Rounded ends are good, but to get them you have to pay attention to hint #1
3. Make sure the hose connection location still works to freely inflate and deflate the bag after the size modification.
4. Follow the cement instructions to the letter.
5. Cement only a small length at a time. Reason: As soon as you apply the cement, it starts to dry. You need to apply cement to opposing surfaces and let it dry before putting the surfaces together. As the cement dries, it totally contorts the bag material, curling it up every which way.
To prevent this, apply a few layers of masking tape to the backside of the flap being glued. This will prevent the rubber bag material from contorting as the glue dries. Still, experiment on scrap first and even then do only a small portion of sealing at a time.
6. Applying the glue is messy and hard to contol becuz it "threads". Use masking tape to mask any areas you don't want the glue. By masking, you can make a very precise glue band along the gluing tab on the bag.
Carefully but quickly remove this mask as soon as the glue is applied or the tape will pull the glue off of the glue application area.
7. Before appying any glue, use a small file or diamond file to really roughen the bag srface at the glue joint areas. The rougher the better - gives the neoprene cement something to bite into.
8. After gluing and shaping the new bag, dust with talcum powder to seal any exposed sticky glue areas. The talc will leave a smooth non-sticky surface.
9. Carefully wet wipe all excess talc off the bag or it will find its way to your air pump seals and cause a slow leak resulting in "mysterious" deflation of your bladder.
Best of luck. It's much easier than the above makes it sound, but do practice first.
As Tim said, good neoprene cement is available at any scuba shop.

[virg]

Thanks for the extra information,

Thanks for the extra information, DanL. It all makes sense to me (now that's a scarey thought).

I really do appreciate the input!

Virg