Posted 5/4/2021 20:24 (#8987674 - in reply to #8987616) Subject: RE: metal tempering
1 hour east of ol cheyenne
Heat it orange hot and let it air cool several times to soften it don't let it cool all the way maybe 200* then heat again then after it fully cools slowly try a high quality LH bit. Could also try and blow it out with the torch then clean up the threads but a quarter inch hole is kinda small for this method especially if it is a blind hole. A tap is bad news as it could have crossed the threads before breaking and might not just unscrew like a bolt would. I wont use a drill or impact on a tap even on open holes. Was it a bottoming tap?