`When I put in this patch because of a poorly placed pre-carve lock inlet, I couldn't file a straight enough glue surface to match the patch and the stock without gaps. I ended up blackening my patch with oil lamp soot and inletting it just like we would a metal part. I went slowly and removed the black marks until I had a seamless fit. Just a tip to get an invisible patch fit.
If you use the right glue and have a perfect fit, I don't think you need to pin the patch in place, your glue joint will be stronger than the original wood.
Patch blackened and inlet, as you can see the patch inlet has a gentle S curve to it as well as rounded ends. There is a paper pattern glued to the patch in this picture.
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Glued, I used my go to bow making glue called Unibond, very tough and made to be slightly flexible. I can glue a bamboo backing on an osage bow with this glue, shoot the bow 100,000 times and it won't turn loose. The hardner comes in several different colors to match what ever wood you are using.
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Filed down and re-inlet;
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Done;
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