My project was inspired by another Instructable: http://www.instructables.com/id/HOWTO-Compression-Connectors/.
Step 1: Supplies & Tools
3/4 inch hardwood
Washer (Metal or Plastic)
J-B Weld (super strong two-part epoxy)
Drill (not shown)
Hole-saw blade (1 3/4", to fit the body of the caulking gun)
Drill bits (1/4", 3/8" & 5/16")
Bench vise (not shown, to hold disc & washer while cutting slots)
In the picture:
Top row - Hole saw blade, drill bits (1/4", 5/16", 3/8"), metal file, rat-tail file, metal saw, coping saw
Bottom left - J B Weld
Step 2: Cutting the Holder and Pusher
I then sanded down both pieces.
Step 3: Making the Holder
The second picture shows a dual coupler with wallplate I got at a dollar store.
Step 4: Making the Pusher
After the first use I noticed that the blue collar was leaving a mark in the wood so I added a metal washer. I cut a slot in it to match the wood, cleaned up with a metal file. Held on with J-B Weld too.