Tom, can the backlash add on be changed to add on negative an no add in positive direction. That would be
a typical convention say in a manual lathe.
George
5 axis CNC Router/3d printer
Moderators: TomKerekes, dynomotion
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TomKerekes
- Posts: 2546
- Joined: Mon Dec 04, 2017 1:49 am
Re: 5 axis CNC Router/3d printer
Hi George,
I don't think that should be necessary. As long as there is an addition one way or another it should work the same. The only issue should be with enabling where we don't necessarily know where the machine physically is within the backlash. We assume we are in the negative end of the backlash. One step negative will just move one step as the backlash should be already taken out in that direction. One step positive will move the backlash amount plus one step to take out the backlash. So make sure the axis was last moved negative before Zeroing/Re-enabling.
I don't think that should be necessary. As long as there is an addition one way or another it should work the same. The only issue should be with enabling where we don't necessarily know where the machine physically is within the backlash. We assume we are in the negative end of the backlash. One step negative will just move one step as the backlash should be already taken out in that direction. One step positive will move the backlash amount plus one step to take out the backlash. So make sure the axis was last moved negative before Zeroing/Re-enabling.
Regards,
Tom Kerekes
Dynomotion, Inc.
Tom Kerekes
Dynomotion, Inc.
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George Butty
- Posts: 104
- Joined: Sun Mar 22, 2020 9:36 pm
Re: 5 axis CNC Router/3d printer
Hi Tom, solved my backlash problem. It was my gearbox for the B&C axis. Was missing shims
on side of one gear set. Any ways ran into another strange problem. Not sure if it is a posting
problem or not. I have attached two files and the larger file is a combination of two sets of
surfaces I am trying to machine. The program works fine on the first set of surfaces and
then when it gets to line 29047( set M00 to stop machine at this point) the machine moves into position
to cut the remaining surfaces. Head turns into position and starts cutting. The problem is that the cutter
is out of position and seems to cut a scaled movement from what it should be (out by inches). Makes the patterned move
but seems to be running at half the scale and not following contures the way it should. If I run the file in Kmotioncnc in simulation mode it shows that it's running correctly. I reposted just the surfaces I am having problems with to isolate them out and have same
problem. (smaller file). Looks good in simulation mode but way off in actual positions. Any Idea's?
George
on side of one gear set. Any ways ran into another strange problem. Not sure if it is a posting
problem or not. I have attached two files and the larger file is a combination of two sets of
surfaces I am trying to machine. The program works fine on the first set of surfaces and
then when it gets to line 29047( set M00 to stop machine at this point) the machine moves into position
to cut the remaining surfaces. Head turns into position and starts cutting. The problem is that the cutter
is out of position and seems to cut a scaled movement from what it should be (out by inches). Makes the patterned move
but seems to be running at half the scale and not following contures the way it should. If I run the file in Kmotioncnc in simulation mode it shows that it's running correctly. I reposted just the surfaces I am having problems with to isolate them out and have same
problem. (smaller file). Looks good in simulation mode but way off in actual positions. Any Idea's?
George
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George Butty
- Posts: 104
- Joined: Sun Mar 22, 2020 9:36 pm
Re: 5 axis CNC Router/3d printer
HI Tom, sorry about last post. Found the problem, had wrong Tool length offset. Looked good on first set of surfaces but
was off by a mile too.
George
was off by a mile too.
George