problem with G31 speed

[acourtjester]

I have run into a new problem with converting my new table from router to plasma. For some reason the probe is giving me trouble. I want to change the feed rate for the probe, and have not found a solution. I have tried to edit the Post processor with no luck. Looked on the web for info but no can be found, other talk about it but no info on how to change it. I can single step the G-code and the thing works as it should, but under normal operation it does not move as it should. I have a tool change for the router bit which uses the probe under a snippet and that works great.
I am using Mach 3 with a USB BOB
N0100 M06 T3 ( Plasma, 0.055 inch kerf shielded 16 Ga)
N0110 G00 X0.0512 Y-0.0787 Z0.5000
N0120 G31 Z -100 F19.685
N0130 G92 Z0.0
N0140 G00 Z0.00
N0150 G92 Z0.0
N0160 Z0.1500

[robertspark]

Probing is a motion controller routine... So it is controlled within the motion controller.

If you place a Fxxxx in the line just above the g31 does that sort it?

[acourtjester]

I was looking for a change that would be done so each time I used the probe, so I did not need to manually make the change in the G-code. I need to have it in the post processor so the g-code is generated with it.

[djreiswig]

Try moving the F in the post probing routine so it is placed on the line above the G31 line. If you're not sure, post this section of the pp so we can see it.

[robertspark]

I was looking for a change that would be done so each time I used the probe, so I did not need to manually make the change in the G-code. I need to have it in the post processor so the g-code is generated with it.

Send me / post your post processor and I'll edit it and send it back (quicker than waffling on about it)

[acourtjester]

Thanks Robert I will continue trying differrent things here.

[robertspark]

Tom,

Try this one (I just edited around line 96, added 2 lines and commented one line out)

Plasma PriceCNC AVHC10 THC zFloat 2 Les With Pierce Delay- G31 ROB edit.zip

(1.51 KiB) Downloaded 38 times

[robertspark]

Thanks Robert I will continue trying differrent things here.

Tom,

Try this one (I just edited around line 96, added 2 lines and commented one line out)

Plasma PriceCNC AVHC10 THC zFloat 2 Les With Pierce Delay- G31 ROB edit.zip

(1.51 KiB) Downloaded 40 times

[acourtjester]

thanks for the reply Robert, it did not change the operation, now what did was I added a pause before the G31 command line and that fixed it ,it now works as I wanted. There seems to be a funny thing happening and I heard this also in the "change tool" button I added.
When the G31 command is given the Z winds up slow then increases speed not at all what I expect from a stepper. No other time does it act like that. Hit the page up/down and z reacts like X and Y quick start and movement.
Now how to install that pause before the G31 command line in the post processor????

[robertspark]

How much delay works and I will add the number

G4 Pxxx?

[acourtjester]

I have edited the post with a line above the g31 command line and it creates a G-code with the delay in it.
I copied another line and change the wording to fit.

post fix.JPG (53.09 KiB) Viewed 649 times

[robertspark]

I have edited the post with a line above the g31 command line and it creates a G-code with the delay in it.
I copied another line and change the wording to fit.
post fix.JPG

yup that will work, once you get the hang of it the post processor is easy to modify.

you don't need the "/n" at the beginning as /n just means new line (but it will work just fine with or without it)

[acourtjester]

Thanks for your help, I had done this before when switching from a floating head surface sensor (G28) to ohmic sensor (G31).
the copy and paste was better then my trying to type in a line, I kept getting a sad face with a tongue sticking out at me when I would save it

[robertspark]

Why reinvent the wheel... That is what copy and paste is for.... If we all spent the time doing things our own unique way from scratch every time we would never get anywhere progress wise