On Tue, Nov 18, 2014 at 6:47 AM, Gene Heskett <[email protected]> wrote:
> On Tuesday 18 November 2014 05:52:16 Mark Wendt did opine > And Gene did reply: > > On Tue, Nov 18, 2014 at 5:42 AM, Viesturs Lؤپcis > > <[email protected]> > > > > wrote: > > > 2014-11-18 12:29 GMT+02:00 Mark Wendt <[email protected]>: > > > > is there any way with screw mapping that I could "adjust" the Z > > > > axis with screw mapping so as it hits each individual "inch" along > > > > the X axis? > > > > > > IMHO something like that might be done with a small "compensation > > > table", which takes X position, looks up necessary Z compensation > > > amount and then either adds/subtracts it to axis.2.motor-pos.cmd and > > > axis.2.motor-pos-fb respectively (just like thc module) for stepper > > > machine or it can be added to Z position in [slightly customized] > > > kinematics module. > > > For Z axis in particular you might want to take a look at probekins > > > as well. > > > > > > Viesturs > > > > That sounds pretty close to what I was thinking about. > > > > The CNC saw beveler is a two axis machine, X and Z. It's stepper > > based, with two steppers on the X axis, one slaved to the other. I'm > > at work and don't have access to the computer that runs the machine. > > I have manually "probed" the X axis and have a listing of all the > > heights per inch of the X axis (no way to really use a machine probe > > under probekins due to the nature of beast). But mapping out Z axis > > height for a given X position is definitely what I'm interested in > > doing. > > > > Mark > > So would I, Mark. I am not Christan Scientist enough to believe my X table > does not sag/rock in the relatively short ways as it moves its CG off > center. Which, because the x motor is hanging off the right end, is > certainly offset to the right by 4 or 5 inches. The relatively short ways > precludes keeping the CG within the available way length travel for quite > a bit of the work I've done on it. This would I'd assume, also be a > problem with the G0704 & clones. > > Certainly I can probe it and record it, but what do I do with that data > after I have the probe file? I often mount work on the right half of the > table so that its working position is better balanced. It would be nice > to be able to use the full length of the table and believe the resultant > cut is within a couple thou of straight, something I cannot do now with > any confidence that its right. > > > Cheers, Gene Heskett > Gene, The probekins routine that Viesturs pointed out (I did a little bit of reading on that this morning) might just work for you. It does require a probe mapping of the area you want to cover, and does some magical 3D stuff (through the use of matplotlib and stl files). I've also seen a pcb probe program which maps out the top of a PCB and makes corrections to the G Code file to do similar work, but that's using the G Code to do the work, rather than actually mapping an X/Y axis height versus the Z axis height. I need to do some reading to determine a course of action. Andy posted a couple of links I haven't had a chance to get to yet, which may be the simplest solution yet. Mark ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
