My numbers are similar (not exactly the same): Major Dia: 0.3678 Minor Dia: 0.3239 Thread Depth: 0.2555
I am measuring with thread wires (0.029 dia) and am trying to get a pitch dia of between 0.3468 and .3430 (class 2A or better). -Tom > On Jun 5, 2017, at 5:30 AM, andy pugh <bodge...@gmail.com> wrote: > > On 5 June 2017 at 02:22, <tom-...@bgp.nu> wrote: > >> Currently I do that by cutting a diameter with the threading tool. I >> measure that with a micrometer and I enter the DRO value in the tool touch >> off for that tool (I have a routine that leaves the tool at the diameter >> after cutting so this works). But I am wondering, I don’t have a DIAMETER >> value in the tool table for the tool. Should I? Is a zero (or >> non-existant) radius value causing Linuxcnc to think the tool is longer >> than it really is when cutting? > > > How do your numbers compare with line 502 of this spreadsheet? > https://docs.google.com/spreadsheets/d/1m5zkO9-SbQaYWbTPlQXJ2VA73Ys8WgWDrPk_rEukHc0/edit?ts=57064122#gid=0 > > (This is a version of the table I complied 20 years or so ago, but modified > to include the effects of crest and root flattening/rounding) > > The DXF file of the inserts shows a 0.05mm radius, whereas as the web-page > table shows 0.06mm. In either case the tip is rounded, not flat. > > You might consider drawing the thread in CAD, with the exact profile for > the thread and grade required, and then fit an exact drawing of the insert > into it. That might answer the question of how to touch-off and what to. > > It is an interesting puzzle, and I am another who will admit to "creeping > up" on one-off threads. > > -- > atp > "A motorcycle is a bicycle with a pandemonium attachment and is designed > for the especial use of mechanical geniuses, daredevils and lunatics." > — George Fitch, Atlanta Constitution Newspaper, 1916 > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
