I know one call maker that made his out of steel tubing. The commercial ones are made from hardened steel. That way you can cut them out on the band saw and not hurt the jig. I think I paid about $110 each for the 2 I have. Dale
I use a scroll saw and a jig made of square metal tubing to cut out my toneboards. The jig is precut with an angle grinder and then ground down with my bench grinder to the desired shape or taper for the toneboard. Grinding the metal jig for the calls is a trial and error process that will result in the best angle or shape for the toneboard barrel for your call, allowing you to that make calls that will blow easier with greater volume. I use square metal tubing for the cutting jigs and it has a wall thickness of 3/16 inch and measures 1 1/4 by 1 1/4 inches for the 7/8" toneboard. For the 5/8" toneboard, I use smaller 1 inch square tubing and a 1/8" wall thickness.