Here is the Roadrunner from Mach3. I haven't bee able to cut this running any faster then 15ipm. I usualy try to run 40ipm.
Thanks,
Dennis
Mach3 Version R3.043.022
I'm going to try KMotionCNC to see if I can get this to work. I've got a tun of orders to get cut and out the door tomorrow and I really don;t want to be up all night.
Thanks,
Dennis
Here is the Roadrunner from Mach3. I haven't bee able to cut this running any faster then 15ipm. I usualy try to run 40ipm.
Thanks,
Dennis
KMotionCNC's not working for me. The Y-axis is still acting up.
FYI, I've moved everything back to JP7. I swapped stepper drives between Y and Z and JP5 wouldn't work with all of the drives I have...even though their the same model number.
Any luck getting yours to fail?
-Dennis
Hi Dennis,
Actually yes I also see a problem. At various places in the road runner it stalls my bench motor above a certain feed rate of ~45ipm. I don't see the problem with KMotionCNC. It runs fine at 60ipm. I've extracted a fragment of GCode that shows the problem every time in Mach3. It is only about a dozen lines of GCode. The problem occurs sort of at the end of a straightaway before going into a curve. I've also captured the output trajectory in KFLOP and it seems to have a big ringing pulse. At this point my guess would be that it is a bug in our Plugin. I've attached the GCode Fragment. Could you run it and see if you observe the same thing?
But I don't understand why you also have a problem with KMotionCNC if that is the issue.
Regards
TK
Regards
TK http://dynomotion.com
That piece of code runs fine for me.
Mine looses location as its coming around to cut the other foot. The two lines that make up the leg end up overlapping.
-Dennis
Tom,
Do you think it may be worth while to swap the channels between the X and Y axes to see if there's something wrong with the board?
-Dennis
Hi Dennis,
Hmmm more inconsistancies...
I made a change that seems to fix my issues. It removes feature we added a few months ago to improve USB rates. Please give it a try.
Save the Dynomotion.dll in your Mach3\Plugins directory and copy in the one attached here (remove the .txt). See if that makes a difference.
Regards
Regards
TK http://dynomotion.com
I think that is unlikely to be the problem.Do you think it may be worth while to swap the channels between the X and Y axes to see if there's something wrong with the board?
Please try the new plugin.
There is an issue with KFLOP not exactly meeting the spec on direction setup for those drives. And actually the "off" voltage for the inputs is out of spec also (they require more than 4V and less than 0.5V - KFLOP provides 4.5V but about 1V when "off"). The opto LED they show should shut off at 1V but it might shut off too slowly. That may be why at the higher microstepping rates it did unexpected things. That's the only other thing I can think of.
Regards
TK
Regards
TK http://dynomotion.com
I'll give the new plugin a try here in a little bit. I found that if I set the maximum velocity to 20ipm for the Y-axis, it'll run perfectly.
I needed to make some headway on the jobs that have to go out tomorrow. I'll let you know as soon as I can.
Thanks for all your help,
Dennis
Nope. I still had to back by max velocity down to 20 ipm before it was reliable.
Hi Dennis,
Hope you got some product shipped.
I'm not sure what is going on with your system. It may be you have a mechanical resonance problem.
To look for a mechanical resonance it can be useful to try a long move with super low acceleration. This gradually sweeps through the full frequency spectrum. You can do this with the Step Response Screen which will remove Mach3, our Plugin, and so forth from the picture.
I think your Y axis has resolution of 4000steps/inch so 60ipm would be 4000 steps/sec. To accelerate over 20 seconds would be acceleration of 200 steps/sec2. So try a move something like:
Max Vel = 4000
Max Accel = 200
Max Jerk = 100000
Size = 100000
Then listen for a stall or a bad chatter at some speed.
Regards
Regards
TK http://dynomotion.com
Tom,
The motors are actually at 16000 steps/inch now.
Attached are a couple screen shots of the configurations where the resonance is bad.
In the pic named "resonance", the resonance starts on the ramp up at about 90% of max speed. The motors stalls right before max speed and then remains stalled for about the first third of the ramp down.
In the pic named "resonance2", the resonance starts and the motor stalls about have way through the ramp up and the motor remains stalled for almost two thirds of the ramp down.
Thanks,
Dennis
Last edited by nova24; 02-14-2012 at 02:30 AM. Reason: typo
FIXED!!!!
The resonance was the issue.
I reduced the Y-axis motor speed by installing a 4:1 timing belt between the motor and the screw.
Now that the motors running slower I'm not hitting those resonance frequencies that stall the motor and I have more torque to boot.
I'm still cautiously optimistic. But, the two test cuts I did, the Mach3 Roadrunner and my machine test pattern, ran perfect at up to 70 ipm!
I have a lot to cut tomorrow so that will be the big test.
Thank you Tom and Gery for all the help.
-Dennis