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Program eratic after a tool change Lathe <resolved. CSS was too high>

Posted: Thu Mar 21, 2024 10:46 am
by PhilipTrueman
I have CNC 12 V5.08 It has been working correctly until last week.
It runs the first program ok then after a tool change it runs the second turning cycle which are all created in conversaional programming.
The tool changes and rapids to the start then it randomly steps off in the X positive and Z positive direction at random amounts of movement.
See video.
https://youtube.com/shorts/9mLSOi1rVkY

Re: Program eratic after a tool change Lathe

Posted: Thu Mar 21, 2024 12:14 pm
by cncsnw
What does this program look like on the graphic preview (F8/Graph) display?

Do programs that you wrote prior to last week still run correctly?

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 5:13 am
by PhilipTrueman
The graph looks normal. The g code looks ok when i look at it in edit.
I dont think it is the program g code.
It has something to do with the tool change that it doesn't like.
It only goes wrong on the second tool change.
It changes to the correct tool for the first operation then only on the second operation after the tool change and after it has made a rapid move to the start of the turning program then it goes wrong.

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 6:52 am
by PhilipTrueman
I changed the x axis motor driver and made new connections on the X and Z axis encoder wires thinking that it could be a bad connection on the wires.
I disconected the encoder wires on the turret motor driver and set the driver to open loop thinking it could have errored out the turret motor.
Still the same problem.

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 7:12 am
by tblough
Immediately after the weird moves with the parting blade, what happens if you restart the program from the beginning? Does the first tool run correctly?

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 7:47 am
by PhilipTrueman
After the eratic moves it just stops when it reaches the x axis limit. Then the software freezes.
Even if i press cycle cancel while making eratic moves.Then the software freezes and i have to re start the software.

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 8:55 am
by PhilipTrueman
I have just changed both the x and Z motor drivers, still the same.
I tried a different Acorn control board, still the same.
Going to install a different version of software.

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 9:07 am
by Ken Rychlik
What about trying the pc tuner? Maybe a communication issue. With it being after a tool change, it makes me wonder about tool offsets G43, G49, Does it go to a G55, G56 ect....

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 10:30 am
by PhilipTrueman
No it is just on G54 work offset.
But there is nothing in the g code telling it to change work offset.

It seems like it has put itself in incremental mode instead of staying in absolute mode and reversed from negative to positive movements.

Re: Program eratic after a tool change Lathe

Posted: Fri Mar 22, 2024 11:42 am
by PhilipTrueman
tblough wrote: Fri Mar 22, 2024 7:12 am Immediately after the weird moves with the parting blade, what happens if you restart the program from the beginning? Does the first tool run correctly?
If i press cycle start again the program runs but the part Z zero has moved positive by about 5 or 6mm, if i run the program a third time the Z part zero moves another 5 or 6mm further away from the part in the positive direction.
I tried just changing from tool 1 to tool 3 for the finishing pass both turning OD.
I have slowed the rapids down by 40% but it still does this sequence.
The second tool change just rapids to what it thinks is part zero then moves away in the positive direction and doesn't take a cut.
Its all very strange what is happening.
I tried re installing a previous version but i couldn't get the turret to work.
Back on V5.08
It stays on G54 work offset all the time and doesn't change. I deleted G55 figures for X position.