My UL tube project...

[SHigSpeed]

Ooops, you guys fell behind a bit... Here are my last few updates:

You know. Im pretty capable at constructing stuff. I am a builder by trade, I made my own wood baits for awhile, Ive completely renmodeled boats and made all kinds of cool stuff. But I gotta tell you bud, what most impresses me with this project is the forethought and precision. I usually just slap ass something together 15 or 20 times before I get something that is really good and consistent. You are gonna get it the first time. It really is impressive!

Thanks for the kind words. I'm really getting a kick out of exercising the old noodle, and so far I haven't run into too many stumbling blocks - but I want to make sure I have all my bases covered.

After letting the valve panels cure overnight, I came back to them and started picking at them. I noticed that the balls of glue away from the part would pick off if I tried. I was hoping that the glue would break down before I could remove the glue. As I flexed the part by simulating someone folding the boat across the valve (I'm hoping nobody would try this but gotta think about these things) I did see the glue pull away from the valve body as well.

Figuring what the heck, I started picking and bending and pulling and I tore the thing apart. Some of the glue stayed on the fabric, some on the valve, but none of it damaged either the fabric or the valve plastic.







So what happened? Not sure... The valve is PVC and the Aquaseal SHOULD be able to bond tight to it. The fabric is raw nylon (urethane coating on the other side) so again - should be able to adhere.

When I took the panel apart, I did smell glue still somewhat so it COULD be that it wasn't fully cured yet. I used the accelerator so it should have been cured in 2 hours. I didn't bother the second panel I made so I'll let that sit until tonight and try tearing that one apart.

Maybe I need to do a primer or a solvent wipedown prior to gluing - I'll try to find some touluene or MEK perhaps...

I can also try to glue to the coated side of the fabric but I've read that Aquaseal isn't supposed to bond well with the heat seal urethane.

I did put together a couple of test pieces last night of fabric glued together raw/raw and coated/coated to see what would happen when I tried to pull it apart. Should really do a raw/coated - forgot...

At any rate, I feel that if you were smart and didn't unduly stress the fabric and valve by flexing or folding it it would have worked just fine. I just would be more comfortable with bulletproof. Failing bulletproof though, had the valve started leaking (YEARS down the line of course ) it wouldn't be impossible to replace. I sure wish I had an ultrasonic sealing machine... Anyone have $15K lying around I can have?

The adventure continues...

_SHig

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Oh BTW, I find it interesting what they did on the Del Canty tube with regards to the valve:



I always wondered why the valve cap was leashed like it was, especially after finding out that as-designed the cap is molded connected. Now I'm wondering if the outer built-up ring of glue that they use is to account for the issues I'm having? The leash connection point is a weak spot for delamination failure when glued (and not RF welded I'm guessing) and perhaps this was their solution?

I wonder if there's a small RF or ultrasonic sealing job shop in town that can just do this one operation for me?

Hmm...

_SHig

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Just thinking out loud here...

One method I'm considering here is as follows (and I'll test it out tonight):

As you can see from the photos above, I'm using a two layer panel at the valve hole. I'll try actually sandwiching the valve (after cutting the cap loose) between the two layers of fabric, heat sealing the fabric to both sides of the valve flange, then putting a bead of glue around the inside "just in case". I'm guessing that even though the bond between the heat seal glue and the PVC valve isn't perfect, with all of the surface area plus the extra glue to keep it airtight, that it won't leak and should be pretty darned robust.

Don't have time now, but I can't wait to try this one out!

_SHig

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Dammit! I just tried to kill myself! <lol> I was playing around with hot cutting the hole in the fabric using a piece of steel tube ground to the right diameter and heated on the stove:





Well, I got it good and hot and was playing around a bit and I guess I must've huffed some plastic because it was bad news time! Talk about wheezing and hacking up yuck... I do a fair bit of welding and when I do I generally wear a fine particle mask to prevent "welder's flu", but next time I'm going to wear my full chemical respirator for sure! Let that be a lesson to you kiddies at home...

While this was bad, it wasn't quite as bad as when I huffed PVC fumes while trying to use a soldering iron to weld a pool floatie. I considered sucking on my oxygen torch and stealing the kid's inhaler to keep from perishing that time!

Okay, now that I'm breathing a little easier, it's off to see "Tangled" with the family. They tell me it's a flyfishing movie but I have my doubts... I had to send them off before me so I could recover!

heh...

_SHig
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