Fusion 360 CAM offsetting profiles

[jixxer.james]

Hey all,

Having an issues with Fusion offsetting my profiles by 0.2mm.

There is noting I can find that mentions that as an option.

The Axis measurements have been checked and all is well.

Checked the Tool options, no offsets in there.

Each profile, weather a pocket or contour, when selected it simulates that it cuts right, but once the code is generated, its all offset by 0.2mm all round.

Any ideas on what to try would be greatly appreciated.

Seems to be only since the new update... Is there something I am missing ???

[engineguy]

Can you please upload the Fusion file you are having issues with?

If you haven`t done this before then use the "Export" facility in Fusion and save the file to your computer somewhere, then when you answer the thread you can attach.

Off the top of my head do you possibly have "Stock to leave" checked and no Finish Pass set ??

Regards

Rob

[engineguy]

@jixxer.james

P.S. Just had a thought, check how/where you have your WCS set in your CAM Setup, if you have for example set stock to a "Relative Box" with 0.2mm bigger than your model and selected the box corner instead of the model then the code will show a 0.2mm difference, if the model corner is selected then here will be no extra 0.2mm, have a look in your setup, maybe the answer

Regards

Rob

[jixxer.james]

From what I can remember from the file, the WCS is the top centre of the box, but I will check ...

Its weird. The OD cuts 0.2mm larger, and the inside cuts 0.2mm smaller...
It's doing my head in. hahaha

Thank in advance for the suggestions and help.

Would love to get back up and running as soon as I can, but obviously with as close as I can to the actual model …
0.2 doesn't sound like a lot, but when it has to fit in something, it's a lot. 

It used to be on point, but then when the new update for Fusion happened, something changed and I can't get it back to what it was ...

[engineguy]

@jixxer.james

Well, it sounds like the issue is at the machine, I checked all your settings and the code produced was correct to the model.

However, if the outside contours are too large and the inner ones too small it sounds like the tool in the machine is smaller than the one programmed in Fusion, I see that you are using a 1/8" (3.175mm) tool in all operations in the program so Fusion will offset the correct amount for that diameter of tool, daft question I know but is it possible that you have a smaller cutter in the machine? 3mm maybe??

Regards

Rob

[jixxer.james]

Am I programming it the right way to get a good result ???

I did my best to measure that tool, and it seemed pretty much on size.

I even tried just drilling a hole to check and that seemed to be as close as 3.175 as I could measure.

Are you suggesting that I use a re-sized tool and retry it all ??? This one was straight out of the box, so I just assumed it was ok.

Is there a way to measure a tool accurately with a set of verniers ???

[engineguy]

@jixxer.james

Your vernier should be close enough

Sounds as though the tool is correct, I  did generate some code for a couple of your contours and it was outputting correctly for the operation and I couldn`t find anything else in you setups etc, all looks good.

Don`t know what control you have on the machine but it`s possible you have an offset in your machine control for tool #1, I can`t think of anything else for now.

I did see that you also had a tool in your tool setup for the program that was a 2.975mm dia, perhaps you selected that by mistake when you generated the toolpath and code, just a wild guess but it is a 0.2 mm difference ??

That does give exactly 0.2mm difference, could be that maybe??

Regards

Rob

[jixxer.james]

Yeah, that random tool may have been an attempt to offset it on the tool diameter to fix the issue.

It didn't. hahaha

I am back onto it today, so hopefully with a reinstall of some programs, I might able to find the issue and sort it out.

Even with the offset on the tool, it still offset the profile, so leaning towards a program issue more than a tech one.

Great in theory, but harder to completely figure out. DOH.