I've stretched my beaver to the max for years (but only when I've had to to get into the next possible size) and I, the local fur buyers, and apparently NAFA have never seen the leather or fur get weakened by tight stretching. My grades have always been very good, when they haven't had bites. Like I posted above, the middle half of the beaver never get's very tight anyway, it's mostly the outside edge. I think if the fur was very thin on the back it was that way before they were ever stretched. But I also have no experience with southern beaver. Maybe they are different.
Trying to compare northern beaver with southern beaver Goldy, lol. Our's have thinner leather than your's for obvious reason's so over stretching them does make them thin. As was said on hoops i like for mine to have some slack in them as they will be tight as banjo strings on them once they have dried out, won't be any 'crinkling' in them.
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