First MYOG climbing pack for custom fit – Design Questions

Hi Sarah.

As to number 1, I think either could work. Being able to remove the foam can be convenient. Also, if you plan to sew through the foam, know that with thicker foams and conventional machines that can be a good way to break needles.

If I were you, I'd fell (sew, flip, top stitch) the side seams for strength, then flip the pack back inside out and triple stitch the bottom seam. Felling the bottom part will be logistically difficult, and having an exposed line of stitching here is usually a recipe for it wearing through unless you seam seal it on the outside.

Good luck.

Regarding the foam along your back, I think it would be easier to put a pocket inside that you can slide it into. Like David said, most foams dense enough to do any good in this scenario will be a pain to sew. Maybe make the 3d mesh into an outside sleeve for your foam. Then you could access the foam for a sit pad without unloading the pack. Sewing the rest of the pack will also be easier without a bulky stiff panel to get in the way of your presser foot.

David is right on the seam finishing too. You won't be able to fell the whole thing with a typical sewing machine. I try to fell where I can, but the final seams end up with binding.

I made a pack with a 3D mesh back panel with CCF under, it also has a sleeve inside to put another CCF sit pad inside. I sewed it inside out, I used Cuben tape to seal all the seams and stitching on the inside making it waterproof, cuben tape sticks very well to Xpac.

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Thanks for the tips!

I think I will go with the internal sleeve to hold the pad. It had not occurred to me that it would be more difficult to put the rest of the pack together with the pad permanently attached.

I like the idea of the cuben tape for seam sealing the inside! I will try that.

Regarding flat felling the seams – I am trying to picture how that will work. Is it actually topologically impossible to fell all of the seams, or is it just extremely difficult since you have to work through the opening in the pack?

Since I am going to seam seal internally, is there any advantage to doing a true felled seam (where I fold 1 longer seam allowance over the shorter one), or would it be fine to just fold both seam allowances to one side and top-stitch. Perhaps it won't look as clean on the inside, but I can't think of another reason.

Sarah

Theoretically it is possible to fell all the seams, its just ridiculously hard to make it work, especially with a stiff fabric like VX-21.

I see no advantage to a true felled seam versus just folding over and sewing through the seam allowance.