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Mike Brooks Custom Muzzleloaders
Now the thumb piece. It needs to be formed to the shape of the wrist. I do this in my swage block, but again you could use a piece of hard wood with a groove in it to do the same thing.
Place the thumb piece on top of the wrist and trace around it and inlet it like we have all the other parts. Shallow gouges come in real handy here again to stamp in the edges of the inletting.
In this picture I've removed the excess wood and I've got it inlet far enough to nail it down. Make some nails just like you did for the butt plate and use them to nail down the thumb piece. After it's nailed down, file down anything that sticks up above the surface of the wood until the whole area is at one level.
This is how it ought to look when you're done.