Inflation bag

[Jamie]

Hi

Here’s a suggestion for an inflation bag that I’m working on. The bag is made out of cuben fibre (this stuff is expensive but super light and strong; I had a rectangular scrap left over from a previous project). The valve solution I have come up with is this: a rubber disc/washer about 2mm thick, with the diameter of the hole roughly 20mm, and the outside diameter of the disc about 60mm. This is bonded to the bag fabric and a 20mm hole cut out in the fabric to match the hole in the rubber disc. An additional 100mm disc of fabric can also be bonded to sandwich the rubber disc between two pieces of fabric. The washer fits snugly and securely over the outside of the Boston valve thread and forms an air tight seal. No need for a hose, and you have the maximum air flow to the valve.

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[Jamie]

I’ve just had a go making a washer from a plastic container lid. If you cut the hole to the right diameter it will thread tightly onto the Boston valve. It provides a good airtight seal and won’t pull off.

[Jamie]

In fact a good quality bin liner bag, some plastic from a food container for the washer (something sturdy, but with a bit of give) and duck tape should do the trick, if you want to improvise.

[Jamie]

The rubber I had was ok, but a little too floppy to create a firm grip. I had some 0.9mm thick TPU sample film called Tuftane which was perfect. Can also just use duck tape to secure the washer to the inflation bag. I have a cheap compass cutter from eBay which cuts perfect circles – definitely recommend investing in one of those.

https://www.ebay.co.uk/p/Jakar-Compass-Circle-Cutter-6-Spares-2-Leads/1606249292?iid=292051332007

• This reply was modified 7 years, 4 months ago by Jamie.

[Matt (Admin)]

This is a great idea!

I’ll tinker with it a bit myself using 40D ripstop instead of Cuben.

Thanks, Jamie!

[Author]

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