Walker Bay 10 DIY Stabilizer Tube

[Minggat]

I just replaced the bolts with eyebolts and put the eye on the underside. In the end I was happier with drilling the holes. I got the flotation tighter up against the hull (not so much with the foam flotation). But I did wind up with one eyebolts midship on each side, eye on the top side. These work with my davit system (see attached).

Let us know how worth it those cones turn out to be. You might be getting a little too far from the KISS system with that. (Keep It Simple Sailor)

[andrewm]

Thanks. I am just afraid to start drilling holes in a beautiful new, shiny boat or permanently gluing anything to it--like using that industrial-strength tape to attach a bolt-rope rail. You're right, I'm also afraid that I'm getting too complicated in designing this system--I only have four weeks of boating weather left out here in the Rockies, so I need to just get it done and play with my new toy for at least a month.

[Minggat]

Welcome to boat ownership.

[andrewm]

Phase 1:
- Took three yards (61 x 108 in.) of 18 oz. PVC (vinyl) coated polyester fabric and cut two 26 x 108 in. sections out of it -- the port and starboard bladders. The cutaway fabric measures about 9 in. and will be used for seam and valve area reinforcing purposes later.
- Notes: You can buy the fabric from awning stores and tarp stores. The 18 oz. per yard fabric is commonly used for inflatable boats. If you want some super rugged fabric, you can also order 40 - 42 oz. per yard material. The lighter fabric costs $12-15 per yard and the heavier material costs $20-25 per yard. I marked the fabric with a 36 in. steel ruler and cut it with a highly sharpened pair of scissors.

[andrewm]

I got the end of my project and ended up with two decent looking torpedo-shaped bladders. Then the harsh reality slapped me in the face--as it always does with my hare-brained DIY projects. The HH-66 glue failed to adhere even though I cleaned both surfaces with water and then medical alcohol before joining them with HH-66. Yes, I let them cure for 24-48 hours. There are pinhole leaks and leaks everywhere and the more I move the seams the more appear--I can't just rip the seams open and glue them again. I'm sitting with $40 of wasted PVC fabric, used $15 glue, two $9 valves, and another $20 I wasted on tools. Please, go ahead and laugh at me--I deserve it! I'm going to just lash six 4.5 inch vinyl boat fenders--a pair next to each seat. I'm done with this project. Please, unless your some kind of whiz like Mingat or the other guy who works in a fab shop -- DON'T TRY THIS!

[Minggat]

Thanx for the compliment. This is why I mentioned "generations" or stages of development for mine. If I'd gotten the first set right, I wouldn't have had much to say.

[clockwork orange]

I am astounded that the HH66 failed, we used to run 100psi in tubes of the same materials you used and never had leaks, we used 10" dia tubes with a 10' overlap seam, sorry it didnt work out.
Steve.

[andrewm]

This can be fixed: Just a setback. I figured out what happened -- there was wax on the PVC sheeting I bought in some places so the HH-66 couldn't bond at some places. Cleaning with alcohol and water failed to remove it all, but I think I can get at it using a small flattened nail file. Using soapy water I located the holes and I can reseal--fewer than I thought. It was the initial shock, really.

My biggest problem now: How do I create ends to the tubes? I glued them shut so it looks like the end of a toothpaste bottle. That seems to be where most of the leaks are and it looks ugly... ideas, suggestions for a nice way to create ends, thanks...

[cat man do]

Perhaps something like this



Kapten Boat Collars

Thinking of EVA foam fenders and contact cement maybe?

[clockwork orange]

I hope it works out Andrew, glueing the ends shut, folding it over and glueing again like the toothpaste tube with the folded part against the hull should be quite neat. You could wrap the aft ends around the transom corner and bolt through the transom through the folded material,the fwd end could be angled to match the bow angle. What diameter did you make the tubes and how wide did you make the gled overlap?
Steve.

[andrewm]

The tubes are roughly eight inches in diameter and 9 ft 4 in long. The overlap seam was only 1 1/8 in. -- a mistake because they should have been double that. I should have cleaned the seam better and applied more glue liberally to the seam edges with a roller instead of the "brush in the can" applicator. The biggest problem has been the pinhole leaks and incomplete fusion of the seam in places. I should have proceeded with a better set of plans--unfolding a design from a CAD program or something.

Other techniques/materials I am exploring: (1) air heat welding* the seams with a slit nozzle on a heat gun and a silicon rubber hand roller tool, (2) using a heavy duty polyurethane coated nylon fabric, and (3) using a much heavier PVC fabric (40 oz instead of the 18 oz).

*I've been getting some good results with the hot air welding as I join pieces of scrap vinyl together. I have to figure out a way of shielding the non-wielding/non-seam areas of the material, perhaps using overlaid tiles to prevent marring/distortion on the non-seam areas of the fabric. I need a different slit nozzle for the heat gun too--3 in. is too wide; 40 mm should do the trick.

[andrewm]

I hope that yellow scares the saltwater crocodiles away from boats. (The gentlemen and ladies Down Under amaze me with your bravado in fishing and recreating in the same habitat as 20-ft blue pointers and crocs.) I wonder how EVA stands up to the kind of abuse we boaters dish out?

[clockwork orange]

Its easy to get wrinkles when glueing the seam which can cause leaks so a little wider is better.
Steve.

[andrewm]

Can anyone help me overcome this hurdle--the ends of the tubes tear open:

At about 5 psi the end seams, which were pinched shut like the end of a toothpaste tube and heat welded (clothes iron and wax paper), tore open. The weld was complete, but the PVC coating tore away from the polyester core. Apparently, welded/glued PVC coated polyester is only strong when force is applied horizontal to its surface--not parallel. The material rips easily that way.

How can I get a nice truncated end that does not put parallel pressure on a seam and tear it open?

P.S. If anyone is sick of me and my project, feel free to let me know ;-)

[andrewm]

If anyone is still thinking of doing this project or interested, I've stumbled onto useful information. To create the ends, you can slide a soccer ball or appropriately sized sphere into the tube and stretch a circular patch of fabric over the end of the ball. You then fold the edges of the overlapping tube down and glue it around the edges of the patch. It creates a blunt end. Create a glued overlap measuring about 3 in. Once I successfully complete the project, I'll release a PDF with instructions.