This is how I check cylinder heads for cracks/leaks at home. Dream big, be fearless, take risk, challenge everything and put Jesus Christ at the center of it all.
First prototype of door actuator on lock chamber. Using threaded rod and delrin. I put threads on the first 1/2″ of the delrin and then clearance drilled the remainder. The motor is 298:1 running about 90 rpm on 11v.