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Are 'I' and 'J' parameters modal?
« on: April 23, 2008, 06:00:18 PM »
Hi,

I am in the process of finalising a fairly complex mould and have completed the CAD and have produced the toolpaths using EdgeCam with a downloaded post processor for Mach2/3. When I simulate the run, in Mach, it falls over saying that I, J, K & R words are all missing. This is where the tool does a profiling cut around some bosses. The first line of the sequence has the I and J words but subsequent ones do not.

Looking through some text on the internet suggests that I and J parameters are modal which should mean they only need placing on the first line of the sequence. Is this true or am I reading it wrong?

It has been rather tedious but I can get round the problem by using a text editor and copying and pasting the missing parameters into each line - time consuming, but it works.

Help would be appreciated.

Mike

PS It takes about three hours to run the program through Mach's simulator to find problems!!!!

vmax549

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Re: Are 'I' and 'J' parameters modal?
« Reply #1 on: April 23, 2008, 08:53:21 PM »
MIKE there is a bug that will give you that particular error when there may not be one. Not seeing your code it is hard to tell if it is the same bug. If MACH does see a real error it may invoke the other bug.

(;-) TP

Offline Chip

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Re: Are 'I' and 'J' parameters modal?
« Reply #2 on: April 23, 2008, 09:18:33 PM »
Hi, Mike

In your G-code post file are there any G90.1 or G91.1 thy set Mach to ether ABS I,J or INC I, J Modes for G02, G03's.

Some Post Processor/CAM's don't add them automatically, You need to modify the Post or add them to your G-code file.

Mach should pick this up during G-code file Loading, What ver of Mach are you runing ?

Hope this Helps, Chip
Re: Are 'I' and 'J' parameters modal?
« Reply #3 on: April 24, 2008, 06:03:52 PM »
Hi guys,

Thanks for the responses.

There are no G90.1 or G91.1 words in the code and there is no problem with code other than the I and J parameters missing on every line after the first. I hope I have successfully attached a screen shot of part of the code. It is a profiling routine that cuts the outside of a circular boss in 0.25mm increments. You will notice on the first line of the routine, the first G2, it has the I and J parameters but the remaining G2s do not.

I have successfully, edited the program, using copy and paste but it was tedious and very easy to miss one as there are 23 of these bosses and the whole program runs to 1/4 million blocks!!! What is more, there are two of these programs, one for the top of a mould and one for the bottom.

Another thing - when running the program through Mach, the latest version incidentally, in simulation mode, is there any way of skipping a faulty line? This program takes nearly two hours to simulate and every time it found an error I had to start again, after fixing the error of course. If a line could be skipped, I could make a note of the line number/s and fix the lot at one go. It has taken the best part of three days to debug these two programs.

Mike

Offline Chip

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Re: Are 'I' and 'J' parameters modal?
« Reply #4 on: April 24, 2008, 09:59:35 PM »
Hi, Mike

I now in LCam's Post there is a feature uses's " [ ] ", If there present [ {Gmode} ], It only post's changes the G-code if the x,y,z value has changed.

Maybe this is what is going on with your EdgeCam's post, Is there a editor, Can you edit your Mach3 Post provided/used by EdgeCam.

Thanks, Chip

Offline Graham Waterworth

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Re: Are 'I' and 'J' parameters modal?
« Reply #5 on: April 25, 2008, 03:50:33 AM »
Hi Mike,

you need to look at the EdgeCAM post, it will have to be set so that IJK's are not modal, or to output commands of equal values.

If you are stuck send me the post.

Graham.
America gave us powered flight, England the steam train and Germany the car.  Who invented the first boat?
Re: Are 'I' and 'J' parameters modal?
« Reply #6 on: April 25, 2008, 04:51:26 PM »
Graham,

Thanks for the offer but I am not sure I can separate the post processor from the program. Edgecam seems to use a code wizard and fancy code generator that uses multiple files to produce code from. The post I downloaded was from the Mach support site (this one) but I notice there is now a message saying it will soon be updated from the company. I have attached the file previously downloaded.

I tried to scratch about with the code wizard but got myself into too much difficulty as it is not very intuitive and far more knowledge is needed than I currently have. In fact I managed to produce about half a million lines of pure rubbish that Mach did not even want to look at.

Unless there is anything you can do with the file, I suspect I will have to carry on hand editing the files as they appear to run just fine, once the graft has been done.

Thanks again,

Mike
Re: Are 'I' and 'J' parameters modal?
« Reply #7 on: April 25, 2008, 04:56:34 PM »
Chip,

Apologies, I didn't respond to your reply.

I think most of what I need to say I put in the reply to Graham. I need more training to be able to edit the post.

Mike

Offline Chip

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Re: Are 'I' and 'J' parameters modal?
« Reply #8 on: April 25, 2008, 10:03:53 PM »
Hi, Mike

Post editing, It's always something, Isn't it.

Thanks, Chip