On 16 April 2013 01:17, Gene Heskett <ghesk...@wdtv.com> wrote: > Ooookkaaaaayyy. Now, what is the diff between probing for a switch closing > where the switch may be mounted on the ways, and my probing for a ground > contact where the contact just happens to be removable because otherwise it > would get in the way of doing any work?
Because the thing you are probing with is of variable length. (the tool). You would have exactly the same problems as you report if, instead, mischievous elves were to randomly move your conventional homing switches around. The issue is that the INI file contains _axis_ home positions, and you are homing with a sensor on the tool-point. Your way will work as long as you never use any touch-off or offsets, but if you do have offsets then the code compensates for them, but the physical world is _also_ compensating for them. > But on my small lathe, how would one go about putting tool offsets into the > tool.tbl that mean something when in changing a tool, the stickout its > clamped up at is effectively completely random give or take 1 cm or so? You can only use a tool table if you have reproducible tool lengths. The solution that people with collet-routers have to use is to do a length-probe after any tool change. Your situation is exactly the same. The difference is that the router folk are not trying to use the length-probe as a home switch too. > To me, it makes 100x as much sense to mount the tool such that it can reach > its cuts ok, drop the gauge on the ways and simply re-home the machine. And I think that you would do better to home to physical marks on the axes (if you lack the IO for switches) and then _probe_ the tool length when you change tools. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis & visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
