Hole Saw Guide
I often encounter older door locks with a 1-1/2 in. bore, which is too small for most new locksets. Enlarging the hole to the current 2-1/8 in. standard is difficult. To keep the hole saw centered and on target, take a couple of scraps of 1×6 and drill a 2-1/8 in. dia. hole centered 2-3/8 in. from the edge of one board. (This is the standard setback for most locks adjust to fit your lockset.) The second board is a backer to prevent the hole from blowing out the other side. Set the first piece flush to the outside edge of the door and cen- tered on the latch hole. Lay the second board behind the hole, then clamp them together. The hole in the scrap will accurately guide the hole saw.
Larry S. Chandler