Shaft collides with stock during simulation

[Anonymous]

I did a search on this error but only found a couple of topics that did not help. I have a relatively simple model that I'm just using to get familiar with CAM. My current issue is that, during simulation, I'm getting these "Shaft collides with part" errors in the last contour operation. That's the last operation that is cutting the outside of my part. First I'm not really sure what that means and second I'm not sure how to avoid it. 

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[LibertyMachine]

The flute length of the tool is .750". The thickness of the part is also .750". It sees these as colliding at the top. Increasing the flute length, even but a few thousandths will make the alarm go away

[markgutierrez]

I have a question about this. In essence, by increasing the flute length we are tricking Fusion 360 into removing the Shaft-collides-with-stock alarms. But is it okay that the shaft collides with the stock? What if the stock was much taller than .750"? Let's say .850". What kind of trouble are we getting into by allowing the shaft the collide with the stock?  Thanks!

[seth.madore]

It all depends on the material, size of tool, rigidity of machine. If you are pushing a tool hard through a tougher material like stainless, the rubbing of the tool shank would likely cause excess heat and premature failure of the tool. Something like plastic or aluminum? I'd probably want to avoid it, but for a single part I'd probably muddle through.

Long story short; avoid it if you can 🙂

[Fueler]

Mark,

If your stock is .750 tall the wiser, safer move is to use an end mill with a longer flue length like 1".

Like Seth was getting at what you are trying to do has a 50/50 chance of working the way you expect and I vote for not likely to work.  

[830403205]

i get it a lot shaft collides with stock.

the easiest way around this and it works  every time, is to use multiple passes,

if the tool is cutting on 1 pass it throws out the error and u have plenty of collisions.

hope this helps u. will not go into the why.