I'm making a couple computer desks. To attach the top to the end case, I'm using T-nuts.
The T-nuts will be attached to the top of the table top and bases will bolt on from inside.
I needed to counter sink the T-nuts so they don't make a bump on the Formica I'll cover the tops with.
I usually cut the countersink with a Forstner bit in my drill press.
But, the tops are fairly big and very heavy, making it very difficult to support level on the drill press.
And, the process was more difficult because I'd have to approach the holes from two different set-ups because of clearance of the drill press pole.
So, I came up with an alternative method. I made a template and used a router with a collar to cut the countersinks.
The countersinks came out well.
A 7/8" template hole produced a 3/4" countersink with a 1/2" straight bit.
The next puzzle (I've always struggled with this) was to put the hole in the center of the countersink.
With a forstner bit, it makes a dimple in the middle, but I've never been able to drill a hole exactly in the center of such a place. The drill always drifts a little off center, even with a drill press.
Routed countersinks don't make a center mark (not that it would do any good).
So, I made this drill guide to center the holes with a bit of 1.25" aluminum rod.
I can drill the hole with a hand drill.
It worked like a charm and the holes are right in the center.
I can't believe I didn't think of this years ago.
This little thing will get used a lot and will have a place in my fixture drawer.