The comprssion chuck is a method for holding an almost finished bowl so that one may turn a decorative foot on the bottom of the bowl and get rid of the unsightly lines left by the four jaw chuck. (lines seen below on the foot of a small bowl)

I started with a standard 6" faceplate for my Dunlap 1942 Lathe I cut out a disk of 1/2" plywood and trued it on the lathe. I then attached the face plate to the plywood with four wood screws (I filed down the points so as not to mar the surface of the bowl) and made allignment circles with a compass at an increasing radius (1/2" at a time) (shown below)

After making the allingment circles, I cut out a matching plywood disk on the band saw, trued it on the lathe as well, and cut a circle out of the middle slightly bigger than the foot but less than the bowl's total diameter. I put the two disks together and drilled three holes (after first laying the holes out.)

I aquired three bolts with wing nuts that were slightly longer than the whole assembly with the bowl in it (very important)

These bolts should be purchased together for each individual bowl. If the bolts are too long or two short it makes the whole process more difficult (and dangerous.)

I then added a few blocks of wood covered in cloth temporarily to the lower plywood disk. This will hopefully support the bowl from the inside and give it more grip and keep the bowl from cracking under the stress (the outside rim of the bowl should be very thin by now because everything is finished except the foot)

In order to hold the bowl in place (to keep it from spinning inside the chuck and being marred) I added a ring of paper towels wrapped in duct tape to the inside of the small hole on the top disk.

I then bolted the two plates together (after aligning the bowl using the pre-drawn allignment rings). Be sure to keep the wing nuts towards the head stock. (very important) This will keep your knucles from being baced by the nuts. By having just the right length bolts, they won't scrape the headstock. After clamping the chuck together Just screw it on to the headstock like a normal faceplate and turn the foot down.

Having diffrent length bolts for the chuck is a neccesity, The bowl (above and below) was deeper and more narrow so the bolts were changed to get the perfect length and a new top plywood disk was made (with a smaller opening for the more narrow bowl.)

The finished product is an incredible looking base for the bowl. The compression chuck hack was worth all of the effort because of its incredible results!

More pictures of wooden bowls