Scott…
My cam offset is ⅛” for a total of ¼” of motion. I haven’t tried for more but I can tell you that I’ll need a longer cam handle if I do!
The leather is “saddle string” from Tandy. However they tan it is the way I use it. I originally bought it for a cane handle wrap before my hip replacement… I found out the hard way that the color isn’t permanent! (at least the burgundy isn’t)
http://www.tandyleatherfactory.com/en-usd/home/department/lacing/5008-200.aspx
SG