One some, I use an adjustable edge groover, then run the #7 overstitch wheel over the groove, then hammer each indention with my awl. A couple problems I have with this:
1) The holes end up appearing too close together compared to other holsters I've seen.
2) I can't see the indentions made by the overstitch wheel very well, but a guy at Tandy recently told me that wetting the groove will help make the indention deeper. Will this cause waterstains on the leather though? How do I deal with that?
3) When I make the holster from folding over a single piece of leather, I prefer to have the holes perfectly aligned, but the only way to do this seems to be to fold it over, glue it, then hammer the awl through both sides of the leather in a single punch. However, I have problems with the awl going through the first layer straight, and coming out the other side crooked, which makes my stitching lines look kinda raggedy. The other option would be to punch the holes in each side separately, but again I'm concerned they won't line up perfectly when I fold the leather over. Another guy recommended using a drill press to make my holes, so there's no danger of getting it crooked.
Anyone have any tips on any of these issues?