There was a nice instructable on how to make a glass bottle cutter that was made at tech shop (http://www.instructables.com/id/Want-to-cut-wine-bottles-Build-this-jig/). It was simple and easy to make, however it only allowed for one size cut unless you re-made the entire rig. Another that was adjustable but used wheels and was a bit complicated (http://www.instructables.com/id/Glass-Bottle-Cutter/). Since I wanted the bottoms cut off for a light project, and my daughter wanted a bottle glass to hold her paint brushes and had most of the materials laying around, I came up with this.
Made from simple materials and straight cuts, its easy to make and inexpensive.
Here is a link to the denatured alcohol lamp. I am planning on using this to heat the bottles after I score them.
Step 1: Material and cuts
1 - 8" X 20" Piece of ply wood or particle board
1 - 2" X 4"
1 - 3/4" X 3" X 6" piece of hard wood
1 - 4 ft piece of 1 1/2" PVC pipe
1 - Kobalt glass cutter
3" deck screws
1 1/2' screws
1 quick grip clamp
3/4" spade bit
Cut the 2/4 into 2 - 17" pieces, 2 - 8" pieces, and 1 - 5 1/2" pices
Cut the PVC into 2 - 20" pieces
With the spade bit drill a 3/4" hole in the center of the ply wood.
Step 2: Assemble the Frame
Center the 5 1/2" piece between the 17" rails. (Second picture)
Place the ply wood with the hole in the center on the frame and mark the hole with a sharpie. (Third picture)