canned cycles G98 G99

[Dan911]

I did a search of this here and found little and it was referring to earlier versions.

What is the behavior with G98 G99 within UCCNC? It seems UCCNC is always in G98 unless G99 called within Gcode. But the problem I been finding is if Gcode is written like example below it's still going to run in G98. If run the Gcode second time it will than run a G99 procedure.

N25 G73 G99 Z-0.75 R0.125 Q0.0625 F5

Also at times with G83 I found it will start pecking at its initial plane not at R value.

Any info on what expected consistent behavior between peck start from initial plane and R would also be appreciated.

Thanks,
Dan

[Dan911]

After doing some extensive testing my results concluded that G98 and G99 has to be invoked before any canned cycle. I have an Alphacam PP and it outputted per example above, G98 or G99 after the canned cycle code. This worked well for Mach3 but will have to adjust PP for UCCNC.

For the G83/G73 pecking cycle, I guess it wouldn't be called a bug... but it's certainly not functioning the way I normally seen it work in Mach3 and what I read on how it should function. If doing multiple holes the first hole works as it should except it don't G0 to R, it uses feedrate for the canned cycle. Every hole after it starts pecking at initial plane, and not at Q value. It seems it's using 1/2 Q value until it reaches R value than works as it should.

Dan

[cncdrive]

Hi Dan,

I will need some time to check this out. I remember that we changed something about the canned cycles, but currently I can't remember what, will have to look it up.
And I think we only made the change in the version which will support the G41/G42, because currently we making no more development, only minor bug fixes on the current test release,
because now there is that version and the new to be soon released version, so now whenever we fix or change something we have to make it 2 times,
so is why I posted the info some time ago that now the development is frozen until we release the version which will support the G41/G42.
Maybe it would be the best idea to get back to this topic after we released that version, because then we will only have to check and change things if required in one place only.

[Dan911]

G98 and G99 drove me crazy for a while, but now I know of it's conditions and work around it's no big deal to me, although I would think it shouldn't make a difference if code was written.

G83 G99 Z-0.75 R0.125 Q0.0625 F5

or...

G99 G83 Z-0.75 R0.125 Q0.0625 F5

Shouldn't the line of code be invoked regardless of order? G83 I rarely use, but if using a high initial plane to avoid clamps with a lot of holes to drill and pecking starting there I can see it being very time consuming and annoying. I did check version 37 and these conditions are there also, this is why when searching I was very surprised not to find more info on it.

Thanks for your response,
Dan