I would think 3/8" carbide rod would fix the flex problem. A bit pricey though.
A quick google search yielded 299.00 for a 24" piece. Im sure 18" would be cheaper.

Make a heavy base, mount a 1" square x approx 18" long steel post to mount the indicator. Silver solder a .437 ball on the 18" carbide rod and mount it on the base.
Should be pretty stiff!!

Last edited by ithaca1; 04/28/23 03:03 PM.

Bill Johnson