Bike frame bag fabric recommendations?

If in a similar situation, i’d probably try this first (below), and if there was any noticeable wear within a reasonable amount of time, then upgrade to the heavier duty Cordura’s mentioned.

https://ripstopbytheroll.com/products/420d-robic

I really like Xpac, it’s become the standard for a reason – great strength-to-weight ratio, waterproof, and non-stretch.  It’s stiffness also lends itself well to bike framebags, it holds it’s shape a bit more than other fabrics.  Last I checked, Quest Outfitters had the best price on it in the retail world.

That said, Cordura works fine too and it’s cheap.  Rockywoods frequently has 500 and 1000d Cordura on sale for cosmetic defects.  It’s hard to beat $5/yard.  For commuting you’d probably be ok with 300 denier but for bikepacking I’d do 500 or 1000.

It strikes be that a frame bag is a relatively simple project to do compared to many other things (eg a pack). Thus, it wouldn’t be too hard to mix and match materials in parts of it as required.

One way to go about determining the areas that are prone to wear, could be to make one out of something rather light, eg a lighter silnylon. Give it a bunch of day riding and commuting. Being a lighter material it might wear faster. Then see the wear areas afterwards. Those are targets for heavier materials on the next build. Perhaps a lighter coloured fabric might help as well.

Thank you all for the feedback. Now I just have pick a fabric and go for it.

Michael