According to ABS master smith Don Hethcoat, “Bowling balls make the perfect vise for knifemakers doing inlays and similar close work where you need both stability and flexibility. You can buy an old bowling ball at a flea market or thrift store for two or three dollars.”
In his own words, here are Don’s six steps.
“Saw off about one-third of the bowling ball, getting rid of the old finger holes. I used a metal band saw but you may have other means.”
“Drill five holes in the flat top of the ball, one at each corner of a square with one in the middle using a half-inch drill bit, then chisel out a cavity in the center of the ball.”
“Fill the opened cavity almost to the top with lead shot to add weight, then seal the shot to the top of the hole with automotive Bondo® filler.”
“Make a round cover for the flat top of the ball using metal, wood or Formica®. Mount your vise on top of this. Mine is a machinist’s vise using its mounting system.”
“Make a base and you’re almost done. I used a round piece of 8-inch pipe cut to 2.5 inches in depth. Fill the pipe with Bondo, cover it with Saran™ Wrap and push the bottom part of the ball into it to make an impression. Clean up the excess Bondo.
“Cut a round piece of suede to fit inside the round cavity so the ball can rotate freely. That’s basically it! Feel free to modify the vise to fit your own scenario.”