Greetings all; I think I have the preamble to my G33-wrapper developing sane values for all the variables.
But it occures to me that if doing a tapered thread, the taper itself should be precut. But that only, because of TLO tolerances, be done with the threading tool. So I am thinking it should do a prep operation to cut the taper first, ding it with a fairly fine feed so as to leave a fairly smooth surface to start the threading operation on. My smallish threading tools have carbide inserts of the rotate 3x for a new edge design, and they are pretty small, would be right at home doing a 40 or 50 tpi thread, maybe even an 80 but I've not tried that, the 50 tpi has been, worked well. Based on that, the tips are pretty sharp. I would guess that a z feed per rev would need to be no more than 3 to 5 thou in order to leave a passably smooth cut behind. The idea is that it should cut the taper, then fall thru to actually cutting the thread proper. This may also need "spring" passes that will actually cut the turned/external threads so the bottom of the cut has a width of P/6 where the tool if properly shaped, might have a tip flat supposedly in the P/8 range. But these are commercial inserts so I have to take their word, or lack thereof, as reasonably correct. They are small enough to max out at a 1/2-13 cut, if they could even do that deep a cut. Anyway, I need a feed rate per rev, and a good swag on the doc for the tapering operation that would allow me to do it all with the same tool. The steel being carved for the external is 1/2" A2 right out of the pvc paper. My nut material is TSC cold rolled, unless I can find some fine threaded 7/16 in grade 8 at TSC. Maybe even 3/8" if I can take enough off the back of the internal tool to allow clearance for the retrace path. This small, that is a problem for sure. But how should the DOC be determined in order to complete the job in no more than 8 or 10 passes when the taper is possibly 1.25mm in radius change over a 20mm z travel? Recommendations intended to extend the tool life so its still decently sharp after doing 10 or 20 such complete operations if indeed that is possible. On the little monster no less. Thanks. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
