2mm would be ridiculously thick and stiff, like a belt. And the "exterior" (skin/hair side) of the leather is the shiny side, not the "inside" (split/suede-like) side. Just reverse your terminology there. Though it's true on bagpipes we tend to put the shiny side facing in, it grows shiny-side-out on the animal. The rough side is called the "flesh" side.outofthebox wrote:From looking around at suppliers websites I think the proper industry term may be cowhide. The exterior looks like suede, but the inside is smooth finished. One of the options that is available in metre length is belt leather - which has a thickness of just over 2mm. This would combine stiffness with a smooth finish on both sides.
Leather is described using several terms- primarily the following: the "cut" (region of the animal's body it was removed from), the "split" (the amount or particular layer of skin the leather was processed from), the "weight" (basically the thickness of the leather, described in ounces) and the "tanning process" used in stabilizing the material (oil tanned, vegetable tanned, chrome tanned, elk tanned, etc).
"Elk tanned" is not elk hide leather, but rather cowhide tanned as if it were elk hide. This yields an airtight leather. I have made bellows from other tanned styles with good results, however. In a double layer, this is less important.
I would start with 3 or 4 oz leather. Even thick leather can be floppy, and thin leather can be stiff. This is a living material, like cane. Real life experience is essential.