Hi,

MACH4 - Does not support G32 only G76

Incorrect, Mach4 supports three Gcodes for threading, g32, g34 and g76 as detailed in LatheGcodeProgramming.pdf
in the Docs folder.

Note that just because Mach, be it Mach3 OR Mach4 supports a Gcode the motion controller is still the device which
enacts it. From OP's account he has discovered that the UC300 does not synchronize thread re-starts....a bit of a problem.

Other motion controllers do support it, in Mach3 the parallel port does, as does the ESS, 57CNC and Hicon.
In Mach4 the ESS, PMDX_424, 57CNC and Hicon all support lathe threading but NOT the Darwin parallel port.

Craig

The uc300 requires an A/B encoder and a single spindle pulse per rev. The encode signals tell teh UC300 what direction the spindle is turning and at what speed. The single spindle index signal sets teh starting point of the thread.
From what I remember from testing all this years ago Mach3 threading with a uc300 worked OK . There were just a few quirks to contend with on certain types of threading.

You can turn threads just fine with UCCNC and the uc300 or the uc400. Being it is encoder controlled you always have perfect thread pitch control.

Last I knew Mach4 cannot thread with a uc300 due to plugin restrictions

(;-) TP

Hi,

Quote

MACH4 - Does not support G32 only G76

Incorrect, Mach4 supports three Gcodes for threading, g32, g34 and g76 as detailed in LatheGcodeProgramming.pdf
in the Docs folder.

Craig

Craig, you are only HALF RIGHT
Copied from the Doc...
G32 1 Threading* N 31
G34 1 Variable Lead Threading* N 33
G35 1 Clockwise Circular Threading* N 34
G36 1 Counterclockwise Circular Threading* N 34
Didn't you notice the * marks?

It means Mach4 Hobby version users will have only G76.

Hi,
really, pages 7 and 8 of the Mach4Lathe.pdf...

Craig

Hi,
really, pages 7 and 8 of the Mach4Lathe.pdf...

Craig

Exactly what I am saying.
Only G76 does NOT have "*" mark
It means G32 G34 G35 G36 are ONLY available if you pay $1,400 for the Mark 4 Industrial Version??

So I am on to the next issue.  I installed a 3rd channel on the original encoder wheel so it now has A/B and Z for an effective ppr of 400.  G32 now works in Mach 3 but with an odd behavior.  I cannot figure out how to cut a straight thread with no movement in X.  In the tests I'm running, it always wants to move X negative by .100" (running diameter mode so it's moving 0.50 radius).  If I enter an X parameter in the G32, the behavior changes but not to any expected number.  The Z movement appears to be correct.

Any ideas on this?

Thanks,

Mark

Hi,
could it be that when the G32 move is executed it is in incremental mode?

If that were the case then the X parameter in the G32 line of code would be X0.0 for a constant diameter thread,
any other X parameter would cause an increase or decrease in diameter.

May I suggest putting a G90 prior to the line containing  G32.

Craig

OK - now I have localized the problem with G32 using Mach 3 Lathe on a Win7 UC300ETH/UB1 setup.  If I call Tool 0, G32 works as expected with no problems.  If I call any tool with a non-zero X-offset in the tool table, G32 moves in X while it's moving in Z (even with no X motion programmed).  I can work around this by doing threading as a separate operation with T0 or by using the threading tool as my reference tool.  Still, I don't understand this problem and would like to fix it.  As usual, any ideas are appreciated - TIA! -Mark

In the example, below, tool 2 has an X offset in the tool table and this code will fail, as it is, by moving the tool in X during the run - if I change the tool call to T0, it runs correctly.  FWIW, the example code uses "made up" values - it isn't a real threading operation. 

G0 G40 G18 G54 G80 G50 G90
T202
M3 S600
g94
G0 X0.525
G0 Z4
G0 X0.5
G32 Z3 F0.01

G0 X0.525
G0 Z4

G0 X0.490
G32 Z3 F0.01

G0 X0.525
G0 Z4
M30