Sorry guys, I got busy yesterday afternoon and forgot. For exact placement, I use and old 14x22 Ludwig keystone badge drum shell that I've just not done anything with yet (picture 4). Yes, some idiot added the double tom mount and painted it black (not me!!).
The first 3 pics are taken on my current custom FG project. I've not drilled it yet, but you can see where I have the rail mount and the lugs marked for drilling. The blue painter's tape just covers the old holes and acts as a backer for the filler -- it will be removed.
1) Picture of the marks for the new holes.
2) The measurement of the spacing, side to side (3 7/8 inches).
3) The measurements from the bearing edge (4 inches and 6 9/16 inches). As you can see, that is not "exact." However, if you've worked with Ludwig drums much, there is variation from drum to drum.
4) The "template" drum. The actual hole size on the Ludwig is 1/4 inch. For what it's worth, I use a slightly larger (9/32") speed bit to drill the wholes, which gives just a little "wiggle" room (a smaller pilot hole first, however).
Hope this helps,
Bill
