2009/9/29 Kirk Wallace <[email protected]>: > I still think your threading problem is due to the Z acceleration issue. > You may try cutting an air thread that is as long as your Z axis will > allow. If your thread wanders the same across the thread then I would > look into your encoder more. If the wander settles to a perfect sync to > your spindle, then look at the accel problem.
As always, it is more complicated than this... G61.1 helps, but only if I turn down my max accel rate, otherwise it drives the stepper too fast and it stalls. It is not a complete solution, either. I almost managed to cut (another) thread in my component (on the basis that only I will ever use it, as long as there is one good thread it will work) by giving it 2" run-up and tweaking the spindle speed for max stability, but it only takes one dodgy run, and it gouges, stalls, and messes up utterly. And it did. Sometimes is settles perfectly adequately, and sometimes it just goes wild. There is clearly too much dither in the current encoder, I will make another one. It does look like more axis acceleration would help, but I have it turned up to the point where I can't home, and it is still not responsive enough. I am slightly confused about the difference between MAXACCELL and STEPGENMAXACCELL, does anyone know what does what? I found that with G61.1, MAXACCELL = 300 and STEPGENMAXACELL = 1000 (!) I could almost use it, but then it stalled the stepper mid cut... I am pretty much convinced that if I could get to the controller parameters that handle the synch between spindle and axis I could tune it to work with my current max accell. It isn't like the machine is horribly sluggish, 300mm/s/s is enough to get up to top speed (and twice the speed needed for threading) in 1mm. -- atp ------------------------------------------------------------------------------ Come build with us! The BlackBerry® Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9-12, 2009. Register now! http://p.sf.net/sfu/devconf _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
