I'm designing a pack for a friend and I need some help choosing main pack body fabric. I'm hoping someone can give me a little insight.
So here are the specs
-32 to 35 liters, IE. large day pack
-must be extremely ruggedly built
-pack will be specifically for geologist/paleontology type field work
-3 liter water bladder + 2 1 liter bottles (does not have to be mounted to sides
-ruck type closure with lid
-sleeve or some sort of mount for crack hammer externally
-2 main compartments one for food/hydration, and one for tool belt respectively
-external sleeve or pocket for metal clip board. (accessible without taking off pack.)
if possble.
I suggested ballistics or 1k d cordura for pack body. But could something like dynema ripstop do the job as well? He would like to keep the weight down without sacrificing durability.
This will be used in the south west, on field digs.
Any suggestions would be greatly appreciated.
Thanks.
Joel

It sounds like abrasion resistance would be the biggest factor in making the pack durable for it's intended use. In that case I think ballistics nylon or 1000d cordura would be better than ripstop dyneema. Most of the ripstop dyneema is 210d and as the nylon threads cover ~90% of the surface area the dyneema doesn't do much for abrasion resistance. You can get 500d "white widow" dyneema ripstop from a couple websites, but it's still a small ratio of dyneema and half the denier of the other fabrics you were considering.

Basically I don't think the dyneema ripstops will be as durable as other fabrics you're considering, and only slightly more durable than the a regular 210d or 500d ripstop nylon.

For the rock pick you should just make an attachment like those used to hold ice axes.