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G84 does not seem to work for me.

PostPosted: Tue Jun 20, 2017 11:39 am
by Derek
This works:
Code: Select all
S150
M03
N9 G00 Z0.3500
N10 X0.0000 Y0.0000
N11  X0.0000 Y0.0000
N12G33.1 Z-0.5 K.0461
N13M03
N15 G00 Z0.3500
N16 M05
N17 M30


This does not:
Code: Select all
S150
M03
N9 G00 Z0.3500
N10 X0.0000 Y0.0000
N11  X0.0000 Y0.0000
N12G84 Z-0.5 K.0461
N14G80
N15 G00 Z0.3500
N16 M05
N17 M30


The spindle turns on and it positions but just sits there like it's waiting for the index signal.
Thanks
Derek

Re: G84 does not seem to work for me.

PostPosted: Tue Jun 20, 2017 12:58 pm
by dezsoe
Set also P parameter to 1. If P is 0 (or not given) it means left handed tapping (G33.2).

Re: G84 does not seem to work for me.

PostPosted: Tue Jun 20, 2017 1:17 pm
by dezsoe
Also, you can shorten you code, because G84 has X and Y coordinates, so you can use:

Code: Select all
S150
M03
G00 Z0.3500
G84 X0.0000 Y0.0000 Z-0.5 K.0461
G80
G00 Z0.3500
M05
M30

Re: G84 does not seem to work for me.

PostPosted: Tue Jun 20, 2017 1:38 pm
by Derek
That fixed it.

Is this a known G84 or one that you created for UCCNC. I tried a few different post processors and couldn't come up with one that produced a G84 that uses K as the pitch. I can edit my post for UCCNC but it would be easier if it was based on a known convention.

Also wouldn't it make more sense since the overwhelming majority of threads are right hand to have no P default to right hand tap. Seems counter intuitive.

Thanks
Derek

Re: G84 does not seem to work for me.

PostPosted: Tue Jun 20, 2017 2:06 pm
by cncdrive
Hi Derek,

Yes, we've unfortunately made the P parameter in reverse as how we wanted to make it.
I mean we wanted to make it that if P missing then it is right hand tap and when P is defined then left hand, but accidentally made it reversed.
Will reverse this.
Also P parameter for direction now does not seems to be the best idea, because it means a dwell e.g. on the Fanucs, so I will change the P to H parameter and will reverse the direction.

On many controls there is no K parameter, because the feedrate and spindle speed sets the pitch, but I think it is better to have a definable pitch parameter otherwise the user always have to figure the pitch...

Re: G84 does not seem to work for me.

PostPosted: Tue Jun 20, 2017 2:11 pm
by dezsoe
G84 exists in some g-code dialects, but with various meaning of parameters. In UCCNC G33.x uses also K parameter, so it came here too. :)

Re: G84 does not seem to work for me.

PostPosted: Thu Jun 22, 2017 4:34 pm
by Vmax549
Normally with G84/74 teh pitch is set in G95 mode Unit per rev as that gives you the pitch directly. OR it could be done from RPM/Feedrate.

i have never seen a seperate parameter for Feed with G84 (K).

Just a thought. (;-) TP