Hi Folks,

... there was a discussion a while ago about how to make little heat sealed pouches in foil airships, and I promised the next time I was making some I'd post some photos and a better explanation, so here it is!

The basic idea is to take a normal plastic 'sandwich bag' of the sort that has a closable lip, and incorporate it in the envelope as a neat and tidy way to hold batteries, ESCs, cameras and so on.

Standard sandwich bags probably aren't helium tight (though they're probably not too bad), so I generally seal them into an extra-large seam, extending the seam into the airship in a sort of flap that holds the bag. The plastic of the bag will join with the sealable side of the foil, and I use 'bake paper' inside the bag to prevent the bag itself from closing up.

So to start with, here are the tools - some sandwich bags, some irons and some bake paper. I use a modelling iron, but with a bit of care a normal household iron can be used as well (providing it gets hot enough).

I find that the sandwich bags are usually a bit bigger than I want, so I cut them down, and then reseal the edges of the bag to the size I want.

This is a pretty straight forward process, but we need to use plenty of bake paper to make sure we don't accidentally melt the plastic of the bag onto the iron, our table, or itself...

Theoretically this step could be combined with the foil sealing step, but I think it's nice to get the bag sorted first. After carefully layering bake paper around and inside the cut down bag the resulting bag with ragged edges is then trimmed to give the final bag.

For the sake of the example I'm using loose foil, but normally this would be the seam joining a pair of airship gores.

The important thing is to again make sure the bake paper is protecting things we don't want to burn or oxidise - so the only real skill is to make sure that the sandwich bag is properly positioned, and make sure that the 'lip' of the bag that is used to open and close it normally is outside the seal - we want to be careful not to accidentally melt that!

If all has gone well, there should now be a small pouch in the foil that can be easily opened and closed for tucking in batteries, cameras and so on. (If you put an RC receiver in, make sure to keep the antenna out and free!)

Thanks for that pegacat! This will come in very handy

Originally Posted by pegacat

If all has gone well, there should now be a small pouch in the foil that can be easily opened and closed for tucking in batteries, cameras and so on. (If you put an RC receiver in, make sure to keep the antenna out and free!)

Very good Idea, I never thought of that solves another problem I am just getting going on making a Embraer E 175 helium balloon Jet slow flyer for indoors Flying .In fact its the post in front of yours or maybe behind your Now ...lol....