Circle cutter 

I have been toying for a while with building a circle cutter 
to mount on the same burning table I have my old Airco Cam-o-graph 
pattern cutter mounted to.

Well it all suddenly fell together. Kind of like my positioner 
project last winter. A confluence of stuff with a few added bits.

The challenge is to rotate a cutting torch at variable speed over 
a burning table. The entire unit also has to swing out of the way 
of the pattern cutter.

I had a variable speed gear motor and controller from an old L-Tec 
wire feeder. I used a 5/8" lovejoy coupling to attach that to a 
worm gear box that has a 7/8" output shaft.

I have it mounted so the output shaft points down. I used a rigid 
shaft coupler to  attache a 7/8"D x 36" bar to the output shaft.
I already had a machine torch with a fancy mount and a rack and 
pinion gear for adjustment. All I had to do was make a mount for 
the rack bar to go horizontal from te lower end of the 7/8" bar.

Ernie Leimkuhler
Topside Welding Instructor
Divers Institute of Technology
Seattle, WA