On Sat, 24 May 2014 18:20:01 -0500, Leon wrote:

And while this is a bit crude as opposed to using a jig, these work
pretty well.

http://www.woodcraft.com/Product/200...wel-and-Tenon-
Centers-516-(10).aspx?keyword=&refcode=10INGOPB&device=

I never had much luck with those. And they don't work for shelf pin
holes. I just drilled about 350 holes (7 bookcases) for shelf pins - I
used this:

http://www.kregtool.com/Shelf-Pin-Jig-Prodview.html

and I doweled the top rail of the face frames together with this:

http://www.woodcraft.com/product/200...eling-jig.aspx