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mattpatt
01-05-2011, 08:05 AM
Hi All,

Here's one that I can't figure out, but not 100% sure whether it's related to Solidcam or my Fadal/Fanuc.

Machining a very simple 2D profile with some internal and external radii.

Choose the profile strategy and click compensation. 8mm endmill. Link in/out is "arc".

This works without issue, but as I'm trying to blend into another surface I found that I need to add to the tool diameter just to hold the tool away from the job a little.

This has never worked for me. If I reduce the diameter in the tool offset list (say from 8mm to 7.9mm), or input something like -0.1mm into the wear it works.

But that's still not my problem.

I went back to Solidcam and changed the tool from 8mm to 8.2mm thinking I could be smart and then fiddle with the tool size of wear in the tool offset. But no matter what I did I just kept getting compensation errors on the screen.

The only way round it was to just put in any old size tool into Solidcam, but it had to be a whole number (8mm, 9mm, 10mm etc) and then I could play with it as much as I needed to in the tool offset. It's now running at a 10mm endmill in solidcam, with compensation, but as a 8.02mm tool in the tool offset list. The actual tool is an 8mm endmill.

Not sure if it says somewhere that I need to use a whole number for the tool size if using compensation. I can't recall having this issue before, but I usually have the right tool for the job.

It doesn't error out in Solidcam in any way, and I can't really see any issues in the Cimco edit. Not sure what's going on!

If my Haas wasn't full on I'd try running the program on that, but I don't want to stop it. But that would tell me if it's a Fanuc or a solidcam problem.

Any ideas?

Cheers,

Matt.

Brakeman Bob
01-07-2011, 03:45 AM
Matt,

Does it alarm out if you check "Use fillet size for last cut" on the Technology page and set the fillet rad at 0.1? This means that your internal corners will be at least Tool Rad + 0.1 (I presume it is the internal corners you are having a problem with). If it is all corners that giving issues, then it sounds like a parameter issue in the control. Fanuc (at least the 16MA does) has a parameter that allows the user to manipulate the mis-match on CRC interference.

mattpatt
01-07-2011, 04:59 AM
Thanks Bob.

I haven't checked anything yet as I'm banging away at another job.

The strange issue is that if I use a whole number in Solidcam, with compensation then i don't get the error on the fanuc if I then use a smaller tool.

The example is program using a 10mm endmill, with compensation. Set an 8mm endmill on the machine, and set 8mm in the diameter offset. Or 8.02mm in this case.

The above works fine.

Another example is program using a 9mm endmill, with compensation. Set an 8mm endmill on the machine, and set 8mm in the diameter offset. Or 8.02mm in this case.

This is also no problem.

Third example is program using a 8.5mm endmill, with compensation. Set an 8mm endmill on the machine, and set 8mm in the diameter offset. Or 8.02mm in this case.

This third example will error out.

It only seems to be the internal corners, so I'll see what I can find out.

Cheers!

Matt.

Brakeman Bob
01-10-2011, 03:08 AM
Internal corners indicate that this is a control / parameter issue. I am not as up to speed as I was with Fanuc parameters, but the answer lies in there somewhere. I'm sorry I cannot be more help. What I will say is that you are only looking for microns - I have seen Fanuc 16MA alarm out with CRC interference with an error of 0.001.