Pick up something to treat the leather after you've reshaped it too. Leather is treated by soaking oils into it or putting a coat of sealer on it. Depending on how deep you cut, it may not be treated to resist water damage, staining and things like that. If you don't care about the color of it. Just put some neatsfoot oil on it.Its made of the natural oils that are in the hide to begin with and really makes the leather resist soaking up water or anything. It will make the lether softer and more supple, maybe make for a grippier handle.I use it a lot on tack for my horses. It does make the the leather a lot darker though.Good luck.
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Fix it right the first time, use Baling Wire !