Posted by David Williamson on January 8, 2014, 3:02 pm, in reply to "Re: damascus pressure"
Cliff, the round stock was purchased as is. The 12 gauge rod is 9/16" diameter and is plated, doesn't have to be and made it harder to machine. The 10 gauge rod is 5/8". The only thing I used the lathe for was drilling the aluminum support rods to the diameter of the gauge rods and they are held in with a set screw.
The hardest thing to do, and it is best done on a milling machine is the taper you have to cut in the rods to accept the spring loaded lever at the top that keeps pressure on the barrel. There is a 1/4" ball bearing on the opposite side and should be drilled to half the diameter. If you use a larger rod, say 5/8" and drill the ball bearing to half the diameter, you are already at .750 which is larger than a 12 gauge bore. The 9/16" rod, .05625 plus half the ball bearing .125 totals .6875. If your spring loaded lever on the opposite side is not flush to the rod, you will never slip it over a full choke barrel .688. Not easy to do on a drill press using a XY table, even with a 3" spindle. I could only take a few thousands cut or else the whole thing shook.