boring 90° to the face of board

[harry strasil]

Boring 90° to the face of a board with a brace can sometimes be frustrating, I solved the problem by using a Bolster, A 2in by 2in block with predrilled holes in it with a drill press. Mark the center and slide the bolster on the bit, start the spur and then slide the Bolster down so its setting tight on the board face and clamp it in place. Gives 4 sided support to the bit and its hard not to drill a straight thru hole. Once you get the bit started straight, its hard to get it crooked.

http://img.photobucket.com/albums/v81/irnsrgn/wood/drillingbolster.jpg

[Mike Henderson]

One thing that I do on a bolster that helps me align it is to draw two lines at 90* to each other through each hole (course, when you have a bunch of holes like the one in the picture, you only need one line through all of them). Then take the lines down the side of the bolster.

When you need a hole, draw two lines at 90* to each other centered on the hole. Place the bolster on the hole, using the lines to center the bolster over the point where you want the hole.

Mike

[Gabriele Piccini]

I Harry,
that worked for me few days ago for boring holes at the edge of some shelve boards for wall pins.
I haven't a drill press, only power drill. I drilled an hole in a square block trying to be the more possible orthogonal to the face. After I checked if the hole was at 90° with both directions and if it wasn't I planned the under face until it was. I done the reference lines as Michael say, too.
Then the hole could drive my drill at 90° to the surface:) .

Naturally all this wasn't "flour of my bag ", i was taught by others with much more experience of myself. I was worried because I haven't a drill press but sometimes the simpler things can work too.