MACH3 g43 and g54 post process problems

[ANDERSONRODANDCHOPPER]

Hello,

I am new to CAM and more specifically fusion 360 CAM.   I am running MACH3 as well.    My problem is after I have homed and zero'd my machine and start cycle the machine runs the program offset left during the 1st facing operation at the correct Z and then during the 2D adaptive operation runs approx .5" high on the z with the same left offset.    Same tool in both operations.   From what I have read this may be a G43 and/or a G54 problem in my code.   I have changed my post process to .tap file extension and do not use G28 and that has helped my "bad character, K word" and Z crashing problems.    My question is how do I set up my post process to eliminate this "offset" or is this a setting in MACH3 I need to adjust.    I do not want to edit code on every program I run if possible.   This seems very time consuming and considering the fact that I don't know what I am doing I feel it sets me up for more problems....

I tried to post the code but it wont let me attach a .TAP file  Is their a way to work around this?

Thank you for your time.

Josh

[LibertyMachine]

Would you be able/willing to share the Fusion file you are working on? It possibly sounds like a setting in one of your operations that might be off.

To export and share: File > Export > Save to local folder. Come back to this thread and attach file.

To share the .tap file: rename it to have a .nc or .txt extension. The Fusion .f3d file will provide us with better info though

[ANDERSONRODANDCHOPPER]

Thank you.  See attached.

[LibertyMachine]

The Adaptive does not run a left or right offset, but is simply computer calculated toolpath. You have it going down to only a half inch deep. Is that what you are refering to, or does it start the adaptive cut a half inch higher than the part?

[ANDERSONRODANDCHOPPER]

First is starts facing at the far top right corner of the part but at the correct Z  and runs extra long on the left and back to the right edge... so on and so forth.   If you stop the program and tell it to return to zero it returns offset to the left approx 1/2".  If I continue to let it run into the adaptive operation it runs that program approx a 1/2 high as well.    In the cam it simulates it correctly but on the machine it is off set.  

[ANDERSONRODANDCHOPPER]

On another note.... Last night I bored some holes using the 2D bore operation with the same tool and it worked fine.    XYZ all perfect.    Although when I tried to change to the radius tool it crashed.   I had to do another post process and run the chamfer as a separate program which ran fine as well.  That is my next lesson, how to learn program in tool changes so the machine pauses and then when I start it again it runs correctly with a different tool without crashing....

[LibertyMachine]

Hmm.... That is odd indeed. What sort of machine are you using? Have you spent any time on the Mach3 forums to see what other people with your configurations are doing?

I'm going to tag @daniel_lyall who knows more than a few things about the Mach3 interface 

[ANDERSONRODANDCHOPPER]

It is a small X2 style mini mill.  It seems to run simple profile and circular programs fine.   Soon as I try to get fancy I start running into problems.      I will start looking on MACH3 as well.   Thank you,

Standing by...

[ANDERSONRODANDCHOPPER]

I put it on you tube real quick so you can see what it is doing.

https://youtu.be/weEhr8yCxvk

[LibertyMachine]

I now see what you mean about the left offset. I was thinking tool offset, you were talking about physically being off the part.

How did you establish your G54? How did you tell the control where the part is?

[ANDERSONRODANDCHOPPER]

I first reference all home in machine cord.  Then I set XYand Z at the stock top center origin of the part which is how I have it set up in my CAM. I have not consciously set up my G54, not really sure about that other than it has to do with offsets???   Again, when I run a simple bore and profile program last night it worked fine.

[LibertyMachine]

It's been a long time since I've used Mach3, so I'm running on memory. 

G54 is the means by which you establish the location of your part, on your table/machine. The program gives you coordinates based on a determined point on the part (this is from your Setup in Fusion). Your machine needs to know where that part is. G54 will give you that ability.

Now, I seem to recall Mach also had the ability to zero out the DRO and treat that as your work offset. Is this what you are doing? If so, than I wonder if you could A) remove the G54 call from your program, or B) is there a value in the G54 field on another page in Mach3?

Sidenote; how are you finding center of the part, eyeball, indicator, edgefinder?

[ANDERSONRODANDCHOPPER]

For now I am centering it real rough with my digital calipers as I am just practicing and I don't need to be exact.   I am comfortable with using the edge finder to be Exact when the time comes.   I have edited out the G43 line and the G54 out of my code and it still ran the same.    Additionally, I have seen in the offset tab of MACH a G54 offset which i have set to 0 as well but i dont know if this is the one I am am looking for.    I can make a quick vid for you if you like to show you my zeroing process.

[ANDERSONRODANDCHOPPER]

Another couple quick vids of the situation.

http://youtu.be/3Ef_Tn23v_U

http://youtu.be/-RTvMoDVgLl

[HughesTooling]

Have you got limit\home switches on the machine? I've built a small engraving machine using Mach3, when I boot up I let it go through the homing procedure this automatically sets G53 (machine coordinate system) when the home is finished the control end up in G54 without me doing anything and recalls any offset I have stored. If you go to the offset tab are the machine and part coordinates different. I haven't looked at this tab for a while because it should just work but there should be a readout of the machine coordinates and they should only change if you home the machine and they will be different than the part system(G54).

Mark

[ANDERSONRODANDCHOPPER]

@HughesTooling

Mark,

Yes, I am using the homing procedure.   For some reason I cannot reset or Zero on any of the G54-G59 tabs.  At the bottom right of the offset page is a couple buttons for save work offsets and save tool offsets neither of which will allow me to save any changes I have made.    I suspect somewhere on this offsets page is my problem but still have not got past it yet.

Thanks

Josh

[daniel_lyall]

@LibertyMachine it's a fusion bug that does not show up anywhere or you can't find it in mach3.

when you home your machine that should be machine zero or home then when you move it to zero to the part that is work zero. and if you zero out the machine at the work X, Y, Z zero that is the offset set.

@ANDERSONRODANDCHOPPER now before you try anything else you need to enter the cancel codes into the MDI, G16, G40, G49 do them one at a time. now home the machine, then set your work zero and run a air test to see if it fixes your problem.

the Mach3 post processor in fusion should be fine with your machine as it is. you won't G28 to be at the end before the X and Y move's so it goes straight up.

with big routers it's not so much of a problem. but mills it is you don't want to hit a clamp or anything so please leave G28 there.

air test 1001.tap see if it run's good

[ANDERSONRODANDCHOPPER]

Update:

I figured it out!!!!!!   It was all my fault....go figure huh.  A bit embarrassing but anyways here is what I did and where I went wrong.

To begin, I was frustrated and decided to completely start over from the beginning as far as my setup on the mill and homing everything.  So as I was tearing everything apart I realized I may have  had the stock fixtured too far to the limits of my table.   I re positioned the stock, homed/zerod as you guys had advised and air tested.  No more weird offset!! I believe what was happening when the machine started, was it ran up against the soft limits and took off from there essentially resetting itself to an offset that would allow it to do its job just in a slightly different location.  When I would stop the program and push return to zero it would go to its "new zero" .   Now that I have it re-positioned I fired it up live, it has been running correctly for the last 1/2 hour and throwin chips like a dream.   What a relief.

So for now I would say that the Fusion Cam is good, no bugs.   I will leave the MDI alone.  How do I leave G28 in without it crashing?  It goes straight up past the limit and crashes.

Thank you again  @LibertyMachine and @daniel_lyall.

Josh

[daniel_lyall]

set your Z home as a limit as well, you can do that 

[ANDERSONRODANDCHOPPER · Accepted solution]

Thanks again everyone.  I will consider this case closed.

Josh