I was working on a project that required a 1-7/8″ forstner bit, and the only size close to this that I had was a 2″ bit. Unfortunately this was not close enough, so I needed a solution, and no stores were open. I decided that the best approach would be to use my router with a template guide, which would make a nice flat bottomed recess that I was looking for, but now I would have to create a template that was slightly larger than my 1-7/8″ target, or roughly 2″. Hmmm, what do I have that can make a 2″ hole for my template? Yep, the forstner bit that was worthless to me only moments ago just became part of my solution.
This is a more of an art than a science. To size this accurately for your application you will need to look at the thickness of your router template walls and the gap between the bit and your template guide, but with a little patience and a bit of luck you might find a combination that produces the perfect sized recess for your project without requiring a trip to the store.
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