How to force negative A-axis movement?

[jerry426]

I am new to HSM but I have many years of experience with machining and 25+ years of software development.

I have a Hurco VMX30U 5-axis machine (table/table) and I need to force ALL A-axis moves to be negative?  I've tried everything I could find regarding the machine setup in the UI and what should have been the needed changes in the post processor javascript code. 

I am working on my first HSM part using a 3+2 approach for all the operations. Most of them are posting as desired with A-axis negative movement while 2 of the parallel ops are posting with A-axis positive movement. 

Unrelated to the A-axis movement problem, I have 2 Pencil operations which should both post at A-90 but one of them is being generated as A0. The only difference on these should be the C-axis rotation with A-90 for both.

Any ideas? I cannot post my part files, but I attached my CPS file.

[Laurens-3DTechDraw]

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@jerry426 wrote:

I am new to HSM but I have many years of experience with machining and 25+ years of software development.

I have a Hurco VMX30U 5-axis machine (table/table) and I need to force ALL A-axis moves to be negative?  I've tried everything I could find regarding the machine setup in the UI and what should have been the needed changes in the post processor javascript code. 

I am working on my first HSM part using a 3+2 approach for all the operations. Most of them are posting as desired with A-axis negative movement while 2 of the parallel ops are posting with A-axis positive movement. 

Unrelated to the A-axis movement problem, I have 2 Pencil operations which should both post at A-90 but one of them is being generated as A0. The only difference on these should be the C-axis rotation with A-90 for both.

Any ideas? I cannot post my part files, but I attached my CPS file.

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Are you sure you are actually post processing with this post processor?

Because I wouldn't expect a positive A-axis move.

[jerry426]

Yes, very sure I am using this one because any other change I make to what it generates shows up as expected in the NC code.

[Laurens-3DTechDraw]

Can you post the G-code of the positive A-axis move?

Like min 5 lines prior to the G68.2 and 5 lines after?

[jerry426]

There are 2 Parallel ops with this problem - and one of those even has a problem with the C-axis rotation being wrong. These are mirrored ops based on a plane we added across the mid line of the part. See below:

this one looks to be correct on the C-axis but the A is still positive:
(Parallel3)
N175125 M33
N175130 M13
N175135 G69
N175140 G0 M140
N175145 G53 G0 Z0.
N175150 G54 X0. Y0. A0. C0.
N175155 G68.2 X0. Y0. Z0. A23.578 C-8.13
N175160 X0. Y0. Z6. A23.578 C-8.13
N175165 M32
N175170 M12
N175175 M8
N175180 G0 X0.2562 Y-0.26
N175185 Z0.7675
N175190 G1 Z0.0188 F100.
N175195 Z-0.0952 F50.

this one is completely wrong on the C-axis and now I am curious as to why, being a mirrored op, the A-axis is not the same value as the other one:

(Parallel3)
N183190 M9
N183195 M1
N183200 T3 M6
N183205 T7
N183210 S11000 M3
N183215 M59
N183220 M126
N183225 G54
N183230 M33
N183235 M13
N183240 G69
N183245 G0 M140
N183250 G53 G0 Z0.
N183255 G54 X0. Y0. A0. C0.
N183260 G68.2 X0. Y0. Z0. A20.705 C90.
N183265 X0. Y0. Z6. A20.705 C90.
N183270 M32
N183275 M12
N183280 M8
N183285 G0 X-0.26 Y0.2562
N183290 Z0.7675
N183295 G1 Z0.0188 F100.
N183300 Z-0.0952 F50.

[Laurens-3DTechDraw · Accepted solution]

@jerry426

I see Autodesk has just made a BETA 5-axis Hurco post available.

I think it might be worth a shot to try that one and see if that helps.

Here is the link: https://forums.autodesk.com/t5/hsm-ideas/generic-hurco-5-axis-post/idi-p/6809997

[jerry426]

Thanks for the heads up on this. I tried it and based on a quick look at the generated code it looks like my above mentioned problems may be fixed. All the A-axis moves are negative and the Pencil operations where I was seeing wacky indexing of A and C look to be correct. I will more carefully review it ASAP and maybe even try to run it on my machine.

[Laurens-3DTechDraw]

@jerry426 since it seemed you did everything right I suspected something in the post to be weird/wrong.

So when I saw that ideaStation post about a 5-Axis Hurco I thought there must have been some changes to the 5-Axis. 

Please let us know if it actually runs good on the machine.

[jerry426]

Sending me to the Hurco 5 axis beta they just released was eventually my solution - after Autodesk explained how to fix my errors in the CPS file where the A and C axis parameters are specified. As of last night I am running my part very successfully with the code generated by the Hurco beta post processor.