I've read different snippets from different threads here about heat sealing nylons for pads and for seam taping. What I'm wondering is if those techniques would transfer to two particular materials.

My Exped DownMat is a horrific pain to inflate with the mini pump, and the stuff sack pump weighs a whopping 6.7 ounces! What I plan to do is cut a hole in the bottom of a Sea to Summit 20L ultrasil dry bag (which will double as my clothing and pad bag). I cut the valve attachment from my Exped mini pump off at the pump body. What I'd like to do is melt/fuse the polyester pump "tube" to the silnylon sack. If I can make it work, will save me 6.3 ounces!

Any suggestions on how to fuse it? If I use an old iron will it work? Or will I have to bond it somehow? Thanks!

That's a good idea. Could you use some kind of sealant? Or fabric epoxy maybe?

Would Silnet work?

You can cut the inner and foam out of the pump sac and it makes very little difference to pumping ability, not as light as what you intend though.

You can NOT heat seal silnylon.
You could probably bond the silnylon to the polyester with any sort of silicone sealant.

Cheers

I was concerned about Silnet/seam sealer having a strong enough bond under pressure, but was looking at McNetts Sil-Fix kit, which has includes "Sil-Fix Silicone Repair Adhesive." Guess I'll try that. I was going to make the hole on the bottom of the bag, but think that on the side near the bottom would work better for air flow. Ultimately it probably won't matter, but I'm thinking I'll glue from the inside instead of attaching the pump on the outside for more strength. Thanks!

EDIT: Hey, question--Would it be completely stupid to sew the fabric pump tube on before seam sealing/gluing?

Edited by 4quietwoods on 12/19/2008 10:59:02 MST.

Sew I made my new pump sack/clothing bag this weekend. Very easy, but the important thing is that it works. I just stitched the air tube/valve to the lower side of the dry sack, cut out the dry sack material behind the tube, and siliconed the seams. Works beautifully. Actually, it makes filling my pad easier and faster, too. Weight-wise, my factory pump sack was 6.5 ounces; my altered dry sack weighs 2.3 ounces, so I only saved 4.2 between the two. However, I eliminated the pad sack, and by making the UL sil dry sack my clothing bag I cut 1.8 ounces from the dry sack I was using. In short, I ultimately saved 8.3 ounces (no dedicated pump sack, lighter clothing sack).

Hi Brad

> I ultimately saved 8.3 ounces (no dedicated pump sack, lighter clothing sack).

A photo is REQUIRED!

Cheers

Hi-
I've been away from my primary residence and camera since last posting... sorry for the delay in getting these up. I'd put more, but they're pretty self-explanatory.

General overview


Inside, after finishing


Cheers-

Manufacturers are you paying attention?!

A brilliant idea cleanly executed. Well done!

I wonder of you could use that for a trail shower too?

That's rather neatly done.
How well does it work?

Cheers

Trail shower is another brilliant idea! I'll try that on my 100 mile AT hike this summer, and report back. By the way, maybe this thread should also be posted in the Multiple Use Gear section.

On a 16 day hike on the JMT last summer, my friend had the trail shower and he did not like it at all, he returned it when he got back. I think it was because it did not provide adequate shower-water flow, I don't know for sure.

Thanks for all the great feedback!

Hi, Roger-
Really does work beautifully. Cuts my inflation time 30-40%, much less hassle (don't have to unroll, open, fluff, re-roll, and compress nearly as much). Easier to burp air out when using as dry sack. I'm considering trimming down a cork to stick in the valve for absolute waterproofness.

Dale, Herman, Roleigh--Well, water would flow out of it, but I'm pretty sure the water would come out at whatever temp you put it in. 42*F stream water will give you an ice-cream headache shower.

Brad,
Great job! Sounds like a pretty easy project with some good weight savings. This makes me want to bring the sewing machine out of hiding.