Thanks for the info. John
-----Original Message----- From: Stephen Wille Padnos [mailto:[EMAIL PROTECTED] Sent: Thursday, October 16, 2008 6:08 PM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] Calibration of Sherline Mill under CNC John Domville wrote: >I have read and printed the 1.3.9.3 notes, don't really understand them. >All I know is that >The default steps set up in the config wizard are all 200. (For every AXIS) >When I tell one of axis to move >1 inch (1.000) the actual tool movement is less than half. (around .480) >That's why I arbitrarily >Plugged in twice the value to see what happened, (400) and when I cut 1 inch >again it came out around(.960) But I am told that is not the way to do it. >I need to find someone with the same 5000 series mill running the same >Sherline controller and see what his settings are. The motors I have are 1/8 >degree. > > 1/8 degree sounds like a strange motor, most steppers are 1.8 degrees (200 steps) per rev - is that what you meant? You should get the information from Sherline. They should be able to tell you how many steps per revolution the motors are, how many microsteps their drivers take (and how to set that, if there are multiple options), whether there's any gearing, and what the screw pitch is. When you enter these numbers into stepconf, it will calculate the correct SCALE value for you. Remember, the numbers in stepconf are just samples - you have to enter meaningful values from your machine documentation to get accurate results. Even if you don't have all the correct numbers, you can measure the travel (measure carefully, all motion afterwards will be based on the accuracy of these measurements). To do this, first set the SCALE "close". Then, jog as far one way as possible then a little bit back (to take up any backlash). Then, use an MDI move, or several large jogs, to move as far as you can for that axis (ideally at least 6" for X, 3" for Y and Z). If you measure the actual travel, you will then have all the information you need to calculate the SCALE. Example: SCALE guess: 400 expected travel: 6" actual travel: 5" The scale would need to be adjusted to 6 (expected)/5 (actual) * 400 (SCALE guess) = 480 The number should be pretty "round", but you can use decimals if necessary (487.931 would be valid, but surprising). You should only have strange numbers if you're using a metric mill (one with a screw pitch in mm) with inch units or vice versa. - Steve ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
