5 axis CNC Router/3d printer

[George Butty]

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

[TomKerekes]

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.

[George Butty]

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

[George Butty]

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

[George Butty]

Hi Tom, working on changing the way I home my machine. Need more accuracy when setting up B and C axis.
The Teknic motors are tricky to set up. Has no index pulse. I have managed to get a consistent home setting
and now I need to set my offset from the zeroed position set by Teknic. I MoveAtVel in the negative direction
which works fine. When I MoveAtVel in positive direction, the axis moves but then Zero's its position. Basically
the axis moves absolute in the negative but moves relative in the positive. I need absolute moves both ways.
using ver. 5.3.1

George

[TomKerekes]

Hi George,

Sorry I don’t understand. The Move should be absolute regardless of starting position and destination. Maybe post your code. Also tell us the initial position, target destination, and what happens. What signal are you using for the zero position?

[George Butty]

Found it, I was enable the BAxis at the wrong time and it reset counter .
Thanks
George

[George Butty]

Hi Tom, can you please look at the attached files. When I home my machine
using the 5 Axis Router Home.c , the X axis (ch1) stops when it hits the limit.
The limit is programed to be disabled at this point. Want to ride over limit.
In KmotionCNC the over limit LED comes on and the axis is stopped.
The XAxis is the only axis that does this . The rest are fine.
When I run the 5 Axis Router X Home Debug.c , it works fine.
For the life of me, I can't find the problem.
Your input would be welcome.
George

[TomKerekes]

B and C are being saved in Y and Z

Code: Select all

    SaveXLimits = ch1->LimitSwitchOptions;
	SaveYLimits = ch2->LimitSwitchOptions;
	SaveZLimits = ch3->LimitSwitchOptions;
	SaveYLimits = ch4->LimitSwitchOptions;
	SaveZLimits = ch5->LimitSwitchOptions;

Z is being restored to X

Code: Select all

    ch1->LimitSwitchOptions = SaveZLimits;  // restore limit setting

HTH

[George Butty]

Thanks Tom, I guess I was brain dead yesterday!

George