The thread was definitely straight, not tapered. Fortunately, we have been able to get around the call out issue easily because we had to have a quartz part machined which would match the Japanese Teflon fitting. Therefore, on the drawing, we called out the pitch and the diameters needed. The quartz parts are made on a lathe, of course and the thread form is ground into the part by a tool-rest mounted rotary diamond wheel grinder. But having said all this, it still is a shame that we couldn't come up with the actual thread form call out for the drawing. <br>
I suppose if we did have the seemingly obscure call out, it would probably give our quartz machinists fits trying to figure it out. Thanks all for your comments and help, I really appreciate it! Ken