Iron Raft packraft build

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Charliecres
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Iron Raft packraft build

Post by Charliecres »

OK, I’ve finally started work on my Iron Raft packraft kit.

After practising sealing using the Jamara Pro Star heat sealing iron on a few scraps, I worked out the right setting to melt the TPU - basically almost full power.

Then the first proper job was to cut out the hole for the Boston valve and a circle of fabric with another hole in the centre to seal it.

The circle and the position of the valve are pre-marked but the actual valve holes aren’t. Nonetheless, it’s easy enough to mark and cut them out.

First of all the valve itself is roughened and glued to the fabric with the supplied glue. I cut a 45mm hole in a couple bits of scrap ply to hold the fabric against the flange while it dried. Then, the next day, the bigger ring of TPU material is ironed to seal the whole thing up.

Image

The next step feels a lot more serious - sealing the tubes to the floor. Before starting I decided to buy a big sheet of 9mm ply to sit on top of our table, both to protect it and give a bigger working surface.

This was a good move. Getting all the tubes lined up is a bit fiddly, especially if they’re trying to slide off the table. I used masking tape to hold them in place before sealing, which worked pretty well.

It’s definitely painstaking work to get a really good seal with no lifting edges. You just have to take your time.

Most of my seams look pretty well aligned but the very last one is a tad gappy, maybe a couple of mm. I’m hoping that’ll adjust out as I work down the tube seam and will at any rate be covered by the seam strip.

Image

The next step is to start sealing the tube seams. The Iron Raft site suggests a heatproof bowl as a base for this but I don’t have one so I’ve made a curved former out of an old bit of 2x4. A guy on the DIY Packraft forum suggests this is a better tool anyway. We’ll see. (I used a side plate as a template for the curve.)

Imageimage uploading

Total time so far: probably about four-five hours. You get quicker as you learn how to use the iron but the tricky bits are yet to come.

Here’s the raft so far, rolled up. Pretty light and packable.

Image
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Richpips
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Re: Iron Raft packraft build

Post by Richpips »

Following. :-bd
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Bearbonesnorm
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Re: Iron Raft packraft build

Post by Bearbonesnorm »

Good work.
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Taylor
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Re: Iron Raft packraft build

Post by Taylor »

Mines only slightly further on than Charlie's having done one curved joint but school summer holidays have put things on hold as I'm doing a lot of daddy duty.
I can attest to the slipperyness of the mixing bowl whilst trying to do the curved joints so when i get some more time to have another go I'll make the wooden arch like Charlie.
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Charliecres
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Re: Iron Raft packraft build

Post by Charliecres »

I completed the first three tube seams today in one marathon session. I think from now on I won’t do more than one seam at a time, to save my back and my sanity.

You join the seams with a roughly 2cm strip that tucks in to join the floor and then overlaps the tube seam (TPU to TPU) along its length.

Heres the floor/tube/strip join:

Image

I am slowly getting the hang of it, I think, but it’s very hard to be neat with the iron I have. It’s just a bit too big and I’ve touched the outer TPU in quite a few places but I think it’ll be OK.

Keeping the seams aligned is quite tricky (and will be worse on the last four as they’re curved in two planes) so you just have to take it a little at a time and ease out any wrinkles. My seams aren’t perfectly butted, but again, I reckon they’ll be OK.

I’ve used another tip from the DIY Packraft forum and covered my former in outward facing masking tape. It really helps to hold things in place.

Image

Might get the last simple seam done one evening after work this week, then I think I’m going to be busy so may not be finished for a while yet.
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Alpinum
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Re: Iron Raft packraft build

Post by Alpinum »

Lovely :-bd
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99percentchimp
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Re: Iron Raft packraft build

Post by 99percentchimp »

Following.... nice work.
My seams aren’t perfectly butted, but again, I reckon they’ll be OK.
definitely painstaking work to get a really good seal with no lifting edges
my seams look pretty well aligned but the very last one is a tad gappy, maybe a couple of mm.
That's the kind of approach that we like to see and that will likely keep you nicely buoyant too :-bd :grin:
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Taylor
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Re: Iron Raft packraft build

Post by Taylor »

Had a session today doing my second simple seam but I used the wooden former that Charlie mentions(without the masking tape) and it's made such a better joint than a metal mixing bowl.
It didn't slip around so was easier to place the seam then iron.
Probably won't get back to it until after the summer holidays now.

Edit

After getting my second seam Bob on I went back to my first one and re-done the whole seam and it looks a whole lot better.
Still time consuming but getting a bit quicker. :-bd
jBay
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Re: Iron Raft packraft build

Post by jBay »

Taylor wrote:Had a session today doing my second simple seam but I used the wooden former that Charlie mentions(without the masking tape) and it's made such a better joint than a metal mixing bowl.
It didn't slip around so was easier to place the seam then iron.
Probably won't get back to it until after the summer holidays now.

Edit

After getting my second seam Bob on I went back to my first one and re-done the whole seam and it looks a whole lot better.
Still time consuming but getting a bit quicker. :-bd
Sounds like a super Airfix kit :)
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99percentchimp
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Re: Iron Raft packraft build

Post by 99percentchimp »

Any updates Charlie or Taylor? How's it going?
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Taylor
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Re: Iron Raft packraft build

Post by Taylor »

Nothing from me.
Busy with work now.
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Charliecres
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Re: Iron Raft packraft build

Post by Charliecres »

Nope, I’ve been too busy and it’s not really a project you can pick up for the odd ten minutes here and there. Hope I might get started again soon. Just in time for winter :roll:
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