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I decided to build a box for the reference ruler, but working with 3/16" mater
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Since I learned to make scratch stock, it's become the solution on a number of occasions.
One benefit to using scratch stock is you can make profiles that do not exist in router bits. Or, if they do exist, they risk tearing out the wood on such a delicate project. With scratch stock, you can work in both directions, so
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For blanks, I use old band saw blades I picked up—for free—from a lumber yard that was throwing them out.
With a tiny profile like this, it was easier to use the edge of a file as a saw rather than a hacksaw to create the 3/32" wide tooth needed to r
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Once the profile was filed, I honed the shape flat on all surfaces with waterstones. You need very sharp edges for scratch stock to work well.
It took about an hour to make the cutter, but routing a groove takes only minutes.