G92 threading cycle

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paul
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G92 threading cycle

Post by paul » Fri 01 Jul , 2011 14:01 pm

Hi
when trying the G92 example from the help files it only does 1 threading pass then just steps in one line at a time for each X value without making a cutting pass. The example looks right so could it be a bug perhaps?
Cheers
Paul

NØØ5Ø GØØ X16.25 Z5.Ø ;
NØØ6Ø G92 X15.6 Z-4Ø.Ø F2.Ø ;
NØØ7Ø X15.2 ;
NØØ8Ø X14.8 ;
NØØ9Ø X14.5 ;
NØ1ØØ X14.2 ;
NØ11Ø X13.9 ;
NØ12Ø X13.9 ;
NØ13Ø X13.546 ;
NØ14Ø X13.546 ;

jaycnc
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Re: G92 threading cycle

Post by jaycnc » Sat 02 Jul , 2011 20:31 pm

G92, X,Y and F values need to be specified in each line. :)


G92 X?? Y?? F??
G92 X?? Y?? F??

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Re: G92 threading cycle

Post by Denford Admin » Mon 04 Jul , 2011 9:09 am

You're right - the example seems to be suggesting G92 is modal - ie, all subsequent lines will carry out a G92 until another G code (eg G0/G1) is programmed

I'll report it as either an error in the example, or a bug in the software.

dubstar_04
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Re: G92 threading cycle

Post by dubstar_04 » Tue 15 May , 2018 23:13 pm

Denford Admin wrote:You're right - the example seems to be suggesting G92 is modal - ie, all subsequent lines will carry out a G92 until another G code (eg G0/G1) is programmed

I'll report it as either an error in the example, or a bug in the software.

I'm having issues with this at the moment. Did this ever get fixed?

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Re: G92 threading cycle

Post by bpmsl » Sat 21 Jul , 2018 17:51 pm

Hi folks, more threading weirdness.

With the DOS control software my novaturn threaded perfectly, in VRTurning it seems to cut the threads compressed in z.

I discovered that for my 1999 novaturn the steps per mm were different from the default machine setup in the latest VRTurning so I had to change them from 160 to 200 (I also changed the steps per F setting). Are the number of encoder pulses different too? (viewtopic.php?f=42&t=3515)

Also the following block of code runs well on its own (apart from the threads being compressed in Z):-

(THREAD1)
M1
T0101
M06 T0101
G99
G50 S3500
G96 S548 M3
G0 X33.6 Z5.542
G0 Z7.242

G92 X8.938 Z-4.458 F1.5
G92 X8.498 Z-4.458 F1.5
G92 X8.16 Z-4.458 F1.5

G0 X33.6 Z5.542
G28 U0.

But if the above is executed in the whole programme (file attached) after the T0101 tool change and one if not both of the G0 moves the lathe sends the cross slide up to max x and then slowly descends and would crash the tool If i don't stop the programme.

The code is from a fettled Fusion 360 FANUC lathe post.

Any thoughts would be much appreciated.

Cheers
BPM
Attachments
1001.txt
(4.3 KiB) Downloaded 65 times

bpmsl
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Re: G92 threading cycle

Post by bpmsl » Sat 21 Jul , 2018 19:07 pm

bpmsl wrote:Hi folks, more threading weirdness.

With the DOS control software my novaturn threaded perfectly, in VRTurning it seems to cut the threads compressed in z.

I discovered that for my 1999 novaturn the steps per mm were different from the default machine setup in the latest VRTurning so I had to change them from 160 to 200 (I also changed the steps per F setting). Are the number of encoder pulses different too? (viewtopic.php?f=42&t=3515)

...

Any thoughts would be much appreciated.

Cheers
BPM
Further info my Novaturn Encoder is marked as PPR 2000.

The default VR Turning spindle "encoder count" for the novamill in teh latest software is 4000, should I change this to 2000 to match my encoder? Or is there some gearing to consider?

Any thoughts would be much appreciated.

Cheers
BPM
Last edited by bpmsl on Sat 21 Jul , 2018 22:53 pm, edited 1 time in total.

TDIPower
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Re: G92 threading cycle

Post by TDIPower » Sat 21 Jul , 2018 19:51 pm

Would love to be able to help, I'm yet to get my lathe changed over from DOS to VR, interested in where/how you got the Fusion post processor. I could only find one for milling which works well.

I would give it a go on changing the value though, if it works great, if not just change it back!

Pete

bpmsl
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Re: G92 threading cycle

Post by bpmsl » Sun 22 Jul , 2018 10:37 am

Hi Pete,
I've been working with the post developed here
https://groups.google.com/forum/m/#!msg ... 14WNt0AQAJ

It's a work in progress. I'll upload a fettled version when I'm happy it's working relatively well.

I'm going to optical tachometer the spindle and see if the speeds are right. I'm beginning to think the reason for the spindle getting warm might be because its been running at double speed so maxing out at 7000 rpm. If so I hope I haven't damaged the bearings.

We will see! Will post an update when I know more :-).

Cheers
Barry M

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Re: G92 threading cycle

Post by TDIPower » Thu 26 Jul , 2018 21:01 pm

Cheers for that Barry, I had seen something about the Nottingham hack space a while ago, I think I even dload a file but couldn't get fusion to 'see' the postprocessor file. Really hope you can sort the issue out on yours and the Fusion processor too.

My lath conversion is well on the back burner yet again, I had set myself the task of rebuilding the axles on my Landrover this week, it's gone a bit mad and a chassis is now on order! Mind you that job has been on the back burner for 13yrs!

Pete

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