NPT Threads
Often times we are putting an NPT thread into a flat bottom. In the case of an open bottom we run the threads out below the minor dia. However in the case of a blind hole its not possible. We are currently cutting a 1/4 NPT to a max depth of .350". How do you handle this? We take the taper 1.783 deg and work back from the tap drill size. It is a trial and error until we achieve the desaired result. Do you have a better way?
Success is the ability to go from one failure to another with no loss of enthusiasm-Sir Winston Churchill