[300sniper]

first of all i am totally new to cnc machining so i may use some wrong terms or miss some information so please feel free to correct me.

i have a machinist buddy of mine helping me with my first project on my pcnc. we have the program written up and created a fixture using g54-59. the fixture went great but now when we load the program for the parts white and grey arcs are all over the job display screen. it looks like spaghetti. they go way off of the part and we can not find any thing in the program that creates them. we tried dry running the program 3" over the part and g54 goes good. when it goes to the g55, it starts having a mind of it's own. the g55-59 programs were just a copy/paste of the g54 but they are not working correctly.

i loaded the program into the free download of mach 3 here at home and it looks fine. there are none of the white or grey mystery arcs on it. i scrolled through it and it looks fine here.

does any one have any sugestions?

thanks.

[ger21]

Is the IJ mode set the same on both?

[300sniper]

Is the IJ mode set the same on both?

thanks. i'll have to head down to the shop today and check that. after reading your post i found this:

NOTE: If you get funny looking circles when you load the G-code generated with this post into Mach3 do not despair. All is well, but you have to change the "IJ MODE" setting in Mach3. You will find it in Config/State settings.

from this site: http://cnc.novalab.org/mach_files.htm

[300sniper]

i have been letting the program run in the free down load of mach 3 at home and i now see that it is doing the same thing except the lines are not shown on the display. when the program gets to about line 139 it starts making arcs that go way off the part. when i scroll through the program line by line, the tool path looks correct. it is just when it runs that it has a problem.

is there some one that would be willing to look at the program and see if they can find something obvious? i'd really appreciate it.

[ger21]

just post it here and I'll look at it. What version of Mach are you running, and are you using cutter comp by chance?

[300sniper]

just post it here and I'll look at it. What version of Mach are you running, and are you using cutter comp by chance?

i am using mach3 that came with my tormach that i got about a month ago. yes, we are using cutter comp. this is also about where the program starts messing up. again i am new to this so i am listening to what my friend tells me. he said this program would work fine on his machine at work. some things may look weird because he went back in and changed some things trying to trouble shoot it.

[ger21]

It's hard to say, since I don't have all your offsets entered, but I deleted all the drill cycles at the start, and it ran OK after that. But all my offsets were set to 0.

I'm guessing it's a cutter comp error. I'd try upgrading to the latest version and see if that fixes it. Some recent versions had some cutter comp errors in them.

Your saying on a dry run it ran OK until the offsets changed, then it didn't run right? Or does it run correctly, but just display wrong?

If updating Mach doesn't fix it, you might want to send it to Art.

[300sniper]

Your saying on a dry run it ran OK until the offsets changed, then it didn't run right? Or does it run correctly, but just display wrong?

on the dry run it worked fine during the first pocket in g54 with the offset. the second pocket on g54 started having a mind of its own. we even started further into the program to see what happens with the outer profile and it did the same thing. if i remember correctly, the g54 profile worked fine but when it went to g55 it started making some large arcs. we couldn't make any sense of it.

[ger21]

Perhaps it's a bug with the comp and offsets.

One other thing I noticed. Your using D to specify the tool radius for comp. I believe that the D needs to follow the G41 for it to work correctly. I don't think you can call it ahead of time. Should be G41 D4 Xx.xx

Does it actually work the way you're doing it?

[300sniper]

Perhaps it's a bug with the comp and offsets.

One other thing I noticed. Your using D to specify the tool radius for comp. I believe that the D needs to follow the G41 for it to work correctly. I don't think you can call it ahead of time. Should be G41 D4 Xx.xx

Does it actually work the way you're doing it?

i honestly have no idea about that. it seems to be working fine for the first pocket (alltho it was just cutting air). i will ask my friend about that next time i talk to him. he is out of town today.


i just single blocked through the whole program again on the mach3 here at home and it all looks good. it is when i actually run the program it messes up.

[ger21]

I think what you were seeing is a bug in Mach3. I submitted a simple file to Art. He's looking into it, but I wouldn't use offsets and cutter comp together until it's fixed.

[300sniper]

I think what you were seeing is a bug in Mach3. I submitted a simple file to Art. He's looking into it, but I wouldn't use offsets and cutter comp together until it's fixed.

that is what my friend figured was going on also. i was able to make a program with out using the cutter comp and got it to work just fine. i was going to contact them about this also.

i have another question about the mach3. when i try to over ride the spindle speed, it just shuts off. this has about killed a couple cutters but luckily i was paying attention. should i ask tormach about this or artsoft?

[ger21]

Probably check with tormach first