6 point has a very good point,
I was skeptic with using them until I played around with ways to make them and found that if you line it with a durable but plyable liner like either chap cowhide or pigskin (suedes/splits) that you can get of a lighter weight (3-5 oz.) and the durability is amazing especially when paired up with yours, it will stay very plyable and will still have the collapseable holding qualities as well for broadhead use. It's worked wonderful for all of ours although it can be a lengthy process but well worth the efforts. You can use a leather glue (some use Barges) I prefer an absorbing flexible non toxic leather glue when I can't use something natural for these types and it helps for added durability. I've been using this glue for years and it actually bonds/fuses the leather knap to itself when compressed properly.
Killdeer is correct about the braintanned vs. commercial.
Also that kangaroo and pigskin is some of, if not the strongest hides to use for durability/utility kangaroo being the toughest per ounce of availability, from what I learned.
There are so many great ideas from so many others on here, lot's of good info,I'm sure you'll find your project
Shell (on hubby's login)