DIY Donut

[unnamedpeaks]

Hi,

I like to take an inflatable donut with me backpacking. In early season I can snowtube, and in later season I can float on lakes.

It seems easy to make with the DIY packraft fabric. Just two washer shaped pieces of fabric inflate into tubes.

Will anyone help me think through a construction method? How do I seal those two pieces together, I can’t visualize a way of doing it that allows me to close everything air tight at the end.

Topic

[unnamedpeaks]

So, I have a friend who is going to model a version of the Aire Rocketbomb, but a hexagon instead of a octagon for easier assembly. I will be ordering some material and making a test version this winter. I will share plans.

A tube is a really fun thing to bring on a backpacking trip. In early season I have had amazing times snow tubing, and floating around on an alpine lake is always a treat. It’s lighter and simpler than a raft, and no paddle needed, a better option for casual water play on backpacking trips.

[unnamedpeaks]

That looks like the way to do it. I basically want that, but in the lighter weight that would be possible with the 210D fabric. Could put a floor in it and put it together just like a DIY Packraft…I would just need someone to model it out for me in software.

Anyone on here game? I could also see if someone on Fiver could do it

 

R

[David Olsen]

I’m still working on my first project, so don’t take this as advice, just ideas. The simplest thing to do would be to have the TPU side inside and just seal the top and bottom together around the inner and outer of the donut – but that would give you an obvious seam sticking out when inflated, and the pressure would be trying to pull the seams apart. I assume the problem you are imagining is you seal a loop of fabric around the outside of your donut, but when you complete the loop it won’t stick to itself?

Kind of a cop out, but you can buy a sheet of thin fabric with TPU both sides like this. Since it has TPU both sides you can use it almost like glue, to fill in the gap where you need to complete the loop. That’s what I’m planning on doing in a spot where I have several pieces of fabric coming together, and it seemed OK in my prototyping.

Otherwise if you want to stick to single sided, you could fold back one side of the loop and seal the other side on top of it. This will create a small tab that sticks out the side of the donut. Seems a likely spot for leaks though. I would try the join with a few strips of scrap fabric first to see if it looked reasonable. If that doesn’t do it, you could fold back both sides of the loop and seal a patch of fabric over the whole area.

Or, wacky idea… Have the TPU inside for the top half and TPU outside for the bottom half, so you can join them directly to each other. I expect this would be difficult, especially around the inner circle where it is a tight turn.

Thinking about the big picture, keep in mind that this fabric doesn’t stretch like a rubber inner tube. I expect the outside edge of a donut constructed that way would end up very wrinkly when inflated.

[Matt (Admin)]

It’s not exactly a donut, but start by checking out the link in this post: https://www.diypackraft.com/2017/09/08/lightweight-fishing-float-tube/

Cheers!

[Author]

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