Collisions - Bug, or am I misinterpreting?

[HarrisonClassic]

So effectively doing a slot cut though stock for the permitter of an embedded part using a 2D contour

When doing a simulate I have stock and stop on collision selected.

When I look at the progress bar it is suggesting several stock collisions which I don;t understand. The 2D contour is entirely made up of "stock collisions" and I'm not using lead in/out but am doing multiple depth passes so it is in effect "plunging" which is fine. 

When I run the simulate, it does not stop on these red bars but continues so I guess Fusion doesn't think they are actually collisions. It does however stop at the start of the large block of red at the end of the process - I understand that it's my holder striking the stock - I know my tool is too short for that, that's another issue 🙂

Thoughts anyone?

David

[brekmiller]

The error message on your image says "Shaft collides with stock".  The shaft is a non-cutting part of the tool.  Is the tool's shaft the same diameter as the flutes and is your toolpath cutting to a depth that is larger than the height of the flutes?  If so, then the shaft will be touching uncut stock.

Simulation doesn't handle this case very well.  Round off errors mean this is sometimes detected as touching and sometimes not.  Also some users want to be warned when the tool's shaft or holder gets close to stock and others don't want to be warned for rubbing shafts.  There are plans to improve simulation in this regard.

For now, if you don't want to be warned for shaft rubbing, you can reduce the diameter of the shaft by a small amount.

[HarrisonClassic]

Thanks Brek,

There certainly isn't any stock there, but yes it's going deeper than then fluted length.

The stock is removed by a previous adaptive that goes way past the part edge. I'm sorry I showed the toolpath in isolation of the rest of the machining - my bad.

It's wood so having a little bit of unfluted shaft is somewhat tolerable but it would make sense to get a longer bi and cut the chip load down a little to cater for tool stability etc

Thanks

David

[jaredSADUH]

Hi David,

If you don't want to see the collision in your simulation, you could go into your tool selection and edit the tool geometry.  You can make the stick out longer (so the holder doesn't show a crash), the flute length longer (so the shank rubbing doesn't show a crash), change the diameter of the shank or the tool or both...  I'm not sure if that's what you were looking for, but I hope that helps future simulations for you