Can't create a turning profile toolpath

[KerryHarrison]

For some reason, I can't seem to create a very simple turning tool path.

It seems the normal 2D profile shown in blue is not created properly. Almost like Fusion does not see the model correctly. I tried removing the hole and slot that are thru one wall but that made no difference.

Any suggestions?

Files attached.

Thanks!

[Steinwerks · Accepted solution]

So the issue seems twofold here. Initially I thought it was simply due to Spun Profile not being used. After turning that on though it still failed so I messed around some more, made a solid by copying a featureless bit previous in the design history, etc. After just about calling it quits, I decided to try one last ditch effort, and I gave the Setup an X axis definition. It doesn't actually follow anything proper, but it doesn't matter. However, along with Spun Profile, it fixes the issue (for some reason):

@xander.luciano can we log this as a bug?

[KerryHarrison]

All fixed. Thank You!!

[xander.luciano]

@Steinwerks

Thanks for the tag! Logged as CAM-5600

Spun profile creating incorrect geometry has been reported before, but it was mostly from complex or dirty geometry. This one I tried everything with to get working and had very limited success. Notice the double wall on the profile? Even though the profile was successfully generated, it didn't get generated correctly. I had to cut the model in half and eliminate the holes in order for it to be correct. 

Now I have no idea how spun profile works behind the scenes, so I tried a bunch of different things in hopes that I would discover some link so I could recommend a workaround. In the end, I would recommend using separate "clean" bodies for turning operations (as I did in my youtube tutorial). The easiest way I find to do that is with the following workflow.

Skip 1 Minute into the video unless you wanna learn how to pattern holes.

And now for the image dump:

This is technically valid as far as the kernel is concerned, but the profile is incorrect.



Examples of invalid, incorrect profiles.

Hopefully that'll at least serve as a good visual to show what an incorrect valid profile, an invalid, and a valid spun profile all look like.

A good tip I always like to emphasize is "Garbage in, Garbage out." Keep the model as simple as it can be for all operations, and you'll get the best results out.

Hope that helps!
Xander Luciano

p.s. Here's a link to the youtube tutorial on mill/turn operations if anyone's interested: https://www.youtube.com/watch?v=FTQG3Qj3TYg

[Lonnie.Cady]

Attached is a screen cast to that hopefully sheds some light on the problem in the software.

The spun profile will actually work correctly if you delete the snapshot from the time line.  Fusion does not appear to handle capturing the part movement and translating that into the cam side.  Or there is a problem with creating the holes on a part that has been moved.  Either way deleting the snapshot appears to clear it up.

@xander.luciano I believe if you look closely at your last image where you split the part in half, you are still not getting the correct geometry.  If you look it appears as though one side of the spun profile is thicker than the other.  Issues like this have come up in the HSMWorks releases and are tough to see unless you verify the gcode diameter that is being output.

@xander.luciano thanks for sharing the copy body trick.  In many cases though parts wont be machined from native fusion models so fusion really needs to be able to handle spun profile with out creating extra geometry.

I would guess the profile is being spun around the origin before the snapshot causing the body to not be spun around the z axis.

[Lonnie.Cady]

Attached is a file how I would create the tool path.  Just to give you an example of some different settings you can compare to yours.

Some things I changed were

1. added lead in and lead out

2. go home a beginning and end

3. changed from both ways to front to back

4. unchecked allow grooving 

5. added some stock to the od in setup

6. added to backside confinement to turn diameter further for part off tool