G02 G03 Arcs not working

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rbmgf7
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G02 G03 Arcs not working

Post by rbmgf7 »

I can't get G02 G03 to work in my main-use processor. I was actually using it for my router and messing around between processors, the G02 G03 works a lot smoother than the straight moves on arcs.

I'm trying to make it work for my main processor for plasma cutting but I can't get it to work. I can switch to another processor which gives me the G02 and G03 but I lose other functions (THC, probing, etc).

I've been staring at how the settings work on the bottom half of the code for the processors. Seems like the Function OnArc() is what calculates the arc and a setting earlier in the code under function OnInit () as minArcSize determines when it'll be an arc or straight move. Well, I literally copied the code from the working processor into my main-use processor and no change. It'll still post only straight moves.

What else am I missing? If it helps, I use the "Mach3 plasma THC with scriber and backlash compensation" as my main processor and the other one with the working G02 G03 is "Mach3 plasma drill with THC".
Les Newell
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Re: G02 G03 Arcs not working

Post by Les Newell »

Do you need the backlash compensation? Due to the way that post works it has to break arcs into a series of line segments. If you are using Mach3 you need to make sure CV is enabled. If not it will run very slowly and roughly around arcs.
rbmgf7
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Re: G02 G03 Arcs not working

Post by rbmgf7 »

I went to another processor (Mach3 plasma) that seems to be barebones. I was able to post with G02 G03 but this processor doesn't have Probing. I copied the Function Reference() from a working Probing processor to include all the initial settings and declarations but nothing relating to Probing shows up when I post.

Is there something beneath what's editable in the processor that won't allow me to make these changes? I assume the processors are using code that relates to Sheetcam-only functions?
Les Newell
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Re: G02 G03 Arcs not working

Post by Les Newell »

What exactly are you trying to do? If you don't need backlash compensation use the 'Mach2 THC with scriber' post. This does probing. You can ignore the scriber specific stuff.
rbmgf7
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Re: G02 G03 Arcs not working

Post by rbmgf7 »

Just like the subject says, trying to get G02 G03 working. I just discovered the processor you said. Either way, for some reason when I want to add attributes like Probe or Arc to a processor without either function, they still won't work, yet the post still compiles with no errors. Just wondering if there is something beneath the processor that could be edited to make these functions work so I could essential write my own processor.
Les Newell
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Re: G02 G03 Arcs not working

Post by Les Newell »

If you want G02/G03 arcs you can't use backlash compensation. In that case you should start with the 'Mach2 THC with scriber' post as I suggested earlier. It does the probing cycles already.
rbmgf7
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Re: G02 G03 Arcs not working

Post by rbmgf7 »

So how can I write my own processor?
Les Newell
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Re: G02 G03 Arcs not working

Post by Les Newell »

I wouldn't recommend writing one from scratch. Start with one that is close and work from there.
As I asked before, what do you want to do in your post that one of the existing ones does not do?
rbmgf7
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Re: G02 G03 Arcs not working

Post by rbmgf7 »

What's wrong with writing my own processor? I built my table from the ground-up, I also want to know how the software ticks.

As I mentioned earlier, when I added functions to the program from another processor, the processor wasn't responding nor was it giving an error. I don't see any declarations in the setup so not sure what prompts the processor to acknowledge certain functions. I see all the processors for other machines so I figure there is something missing. I figure there has to be some other way than what's visible in the edit screen.
Les Newell
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Re: G02 G03 Arcs not working

Post by Les Newell »

rbmgf7 wrote:What's wrong with writing my own processor?
Nothing. It is likely to be a bit of a learning curve to start from scratch though.
As I mentioned earlier, when I added functions to the program from another processor, the processor wasn't responding nor was it giving an error. I don't see any declarations in the setup so not sure what prompts the processor to acknowledge certain functions. I see all the processors for other machines so I figure there is something missing. I figure there has to be some other way than what's visible in the edit screen.
Have you looked at the documentation? Look in Options->machine->post processor->post documentation

The function you added was Function Reference(). That function is called by some other functions in that post processor. If you didn't include those calls the function would do nothing.
Kirkamiller
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Re: G02 G03 Arcs not working

Post by Kirkamiller »

This is a great thread. I have spent a bit of time trying to figure out how to get the sheetcam post processor to output G02 and G03 commands instead of G01 straight line moves on curves and still have the floating z head rezero z before every pierce cut. The Mach 2 THC with scriber post processor doesn't appear to be in the sheetcam list anymore. I found that the Wright CNC Pro Kit Updated 12-17 worked, it uses the G31 probe and appears to output G02 and G03 commands for curved segments.
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