By Ed BrodyI first became interested in old machinery when the previous owner of my home left an old Shopsmith 10E in the garage for me. What was junk to him has become a valuable machine in my shop, and has fueled my interest in old woodworking machines. In addition to the general purpose woodworking tasks I use it for, I recently found another great use for this machine.
I bought an old 16" Walker Turner bandsaw on ebay. After getting the machine home I proceeded to tear it down and do a complete rebuild. It went fairly smooth, but when I got to the point where I had to machine a crown on the new bandsaw tires I was at a loss. I read Bob Vaughan's articles about building a special jig, or using a milling machine, which I didn't have access to. Then I started thinking about how I could use my Shopsmith to do this. The photos below show what I came up with.
The wheel is mounted on the bandsaw's shaft assembly, which is then clamped to the SS main table. The table is tilted 5 degrees in one direction, and locked in place. The quill is advanced until the sanding disk just makes contact with the tire, and locked in place. Holding the wheel, the SS is turned on and the wheel is rotated against the rotation of the sanding disk. Continue rotating the wheel until a consistent crown is machined.
Next, the SS table is tilted 5 degree in the opposite direction, and the procedure is repeated. The result was a real nice, symmetric crown.
The pictures above show the upper bandsaw wheel. The only difference in machining the lower wheel was in the mounting of the wheel to the SS table. While the upper wheel mounts to a casting with a short machine shaft portion, the lower wheel mounts to the drive shaft. In order to clamp this to the SS, I placed the drive pulley on the shaft, and locked it in place with two set screw collars on either side. I then layed the pulley horizontal on the table, with the shaft extending vertically above, and below the table (through the saw slot). Since each bandsaw is different, you will have to come up with a unique method of doing this for your saw.
After completing the crowning and reassembling the saw, the blade now tracks right in the center of both wheels. This was well worth doing!