Hello Guest it is May 10, 2021, 09:21:58 PM

Author Topic: K values in XY plane error for turning operation  (Read 412 times)

0 Members and 1 Guest are viewing this topic.

K values in XY plane error for turning operation
« on: November 25, 2020, 05:18:47 PM »
I'm trying to turn a ball on the end of a motorcycle push rod. I used the Rounding Canned Cycle in Mach 4. However, when I run the code I get "K word given for arc in XY plane". When I search the net and this forum all the topics refer to milling operations, and not turning.

I've attached a file showing my inputs for the Rounding Cycle.

I've also copied the output code below.

Finally, I've attached my profile.

Why is it looking for the XY plane? What is the K value for? I though I and J control arcs.

Joe



N0 (Machine type - MachMotion Lathe Canned Cycles)
N5 (Filename: C:\Mach4Hobby\GcodeFiles\Parting Cycle.tap)
N10 (Generated on 11/25/20 at 16:58:52)
N15 G00 G40 G54 G64 G80 G90.1 G99 G17 G21 (Safe Start Block)
N20 %


N25 %
N30 (Starting Gcode for Rounding Cycle: RoundingCycle-0)
N35 ([Xi, Zi] = [7.04, 23.46]; [Xf, Zf] = [0.0, 30.5]; Radius = 14.08; Z- Direction; OD)
N40 G50 S2750 (Spindle Speed Cap)
N45 (Roughing)
N50 G00 G40 G54 G64 G80 G90.1 G99 G17 G21 (Safe Start Block)
N55 %


N60 %
N65 T0101 (Tool Change)
N70 G99 (Feed per Revolution)
N75 G97 S600 (Constant Speed)
N80 M03 (Spindle Forward)
N85 M09
N90 G00 X7.240 Z30.615  (Rapid move to Clearance Height)
N95 G01 X6.540 F0.250  (Cut in on X-Axis)
N100 G01 Z26.474 F0.250  (Cut in on Z-Axis)
N105 G03 X7.040 Z25.362 I-3.451 K12.190 F0.250  (Spring Pass Sweep)
N110 G00 X7.240 Z26.574  (Pull out to Retreat)
N115

Offline Graham Waterworth

*
  • *
  •  2,322 2,322
  • Yorkshire Dales, England
    • View Profile
Re: K values in XY plane error for turning operation
« Reply #1 on: November 27, 2020, 08:01:00 PM »
Lathes use XZ plane which is G18 so swap G17 for G18 and try again.
Without engineers the world stops
Re: K values in XY plane error for turning operation
« Reply #2 on: November 28, 2020, 10:33:37 AM »
Thank you, I didn't read the Safety Block - assumed that a lathe canned cycle would choose G18!!

This seems to be a bug in the Canned Cycle

Joe
Diameter output instead of R in Rounding Canned Cycle with Arc center = Incr
« Reply #3 on: November 28, 2020, 11:35:26 AM »
However, there seems to be another issue.

My Arc Center has been set to Incremental in Configure

However, for the inputs shown in the attached Rounding Canned Cycle file Xi7.04, Zi23.46, Xf 0.00, Zf 30.5 and R = 7.04, the GCode output shows a radius of 14.08, instead of the 7.04. Not sure why this is happening.

Joe

Offline Graham Waterworth

*
  • *
  •  2,322 2,322
  • Yorkshire Dales, England
    • View Profile
Re: K values in XY plane error for turning operation
« Reply #4 on: November 28, 2020, 10:02:49 PM »
The X axis works in Diameter unless you have it set to radius mode, most lathes work be in diameter as do lathe CAM systems.
Without engineers the world stops
Re: K values in XY plane error for turning operation
« Reply #5 on: December 01, 2020, 01:48:20 PM »
Thank you, Graham. The machine I use was set to Radius. I reset it to Diameter and the G17 now is switched correctly to G18. Though the code still says [Radius=14.08] when the Radius is 7.04, it actually cuts the correct diameter. Thank you for your help.

Joe