On Monday, December 26, 2011 10:36:04 AM Dave Caroline did opine: > The tool cutting brass is one I found amongst some cutters at a clock > and watch show > It just suited the job, you can also use commercial thread mills > eg > http://www.kennametal.com/en-US/products_services/metalworking/tapping/t > hread_mills/thread_mills_products.jhtml > These of course have to be ordered per tpi, and Kennametal has any pricing hidden behind a login screen. Bad dog they be, no biscuit from me.
> While designed for steel but have a limited range as designed not for > tilting to the correct thread angle > so will produce a concave shape to the thread form if out of design > range (I dont know the maths to show the effect) > but my first attempt did show the error as the tool is large in > diameter compared to thread angle > > note this code lacks sensible centerline finding and b axis angle > although #4 is the value it should be based on > and reviewing it some comments are a bit off :) > > e&oe > > (metric worm cnc prog) > (cnc preamble) > G20 (set inches) > G64 (?) > G90 (set absolute) > G94 (set inches per min) > #<number_of_starts>=1 (#9 number of starts) > (for mod worm calc DP for it) > > #<DP>=25 (#10 DP of system) > #<teeth>=60 > #<pcd_wheel>=[#<teeth>/#<DP>] (d ebug, pcd of wheel #14) > #<pcd_worm>=[[1.25-[#<pcd_wheel>/2]]*2] (de bug, worm pitch dia df > #<pcd_worm>) > #<n_turns>= 6 (#11 number of turns in worm) > #<rotation_angle>=[360 * #<n_turns>] (#1 set rotation degrees) > > #<m>=[1/#<DP>] (#6 m imperial module) > > > #<df>=[#<pcd_worm> / #<m>] (deb ug,q diameter factor #<df>) > #<df_od>=[4 / #<m>] (de bug,q diameter factor #<df_od>) > > #7=[3.14159625*#<number_of_starts> * #<m>] (D EBUG,Lead =pi*1*#<m> L=#7 > ) #8=[#<number_of_starts>/#<df>] > #9=[#<number_of_starts>/#<df_od>] > #2=[atan[#8]/[1] ] (debug,angle of helix #2 angle to rotate > trunnion from vertical when I get one!!) > #<tp_angle>=[atan[#9]/[1] ] (deb ug,angle of helix to rotate ar > tip #<tp_angle>) > #3=[#<n_turns>*#7] (DEB UG,length of cut #3) > #4=[sin[#2] * #3] (DE BUG,y=#4 offset to move to track worm > centerline) #5=[cos[#2] * #3] (DE BUG,shortened Z=#5 because > tilted) > #20=[#4] (D EBUB,corrected direction y offset #20) > G0 X0 Y0 Z0 (move cutter centerline lowest point in line with axis and > touch off) > G0 F1 A-5 (rotate blank back to start+1) > G0 F1 A0 (rotate blank to draw center line) > > G1 F.1 X-.063 Y0 Z0 A0 (move cutter to depth) > G1 F.05 x-.063 Y[0-#20] Z[0-#5] A[0-#<rotation_angle>] (rotate blank 7 > turns) > > G1 F1 X0 Y[0-#20] Z[0-#5] A[0-#<rotation_angle>] (move cutter out) > > (G10 L2 P1 A0) > > (G92 A-2520) > G0 A0 (rotate blank back to start) > G0 X0 Y0 Z0 > > > if email buggers the above see > http://www.archivist.info/cnc/worm2.ngc > Will do, thanks. > > Dave Caroline > > ------------------------------------------------------------------------ > ------ Write once. Port to many. > Get the SDK and tools to simplify cross-platform app development. Create > new or port existing apps to sell to consumers worldwide. Explore the > Intel AppUpSM program developer opportunity. appdeveloper.intel.com/join > http://p.sf.net/sfu/intel-appdev > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> Goes (Went) over like a lead balloon. ------------------------------------------------------------------------------ Write once. Port to many. Get the SDK and tools to simplify cross-platform app development. Create new or port existing apps to sell to consumers worldwide. Explore the Intel AppUpSM program developer opportunity. appdeveloper.intel.com/join http://p.sf.net/sfu/intel-appdev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users