Efficient facing across a diameter

[genxmachining.mill]

Hi, I am trying to face across a diameter using multiple depths but it cuts a lot of air near the beginning. I have defined my stock shape as a cylinder and set up a facing toolpath. Top height is set to stock top, bottom to selected contours. The toolpath still traverses the entire width of the face near the top of the stock. What can I do to ensure the toolpath only cuts where the stock exists?

[johnswetz1982]

File>Export>*.f3d and attach to post so we can better understand what you mean. I THINK based on what you are saying is that you defined your stock as round but it is not really round?

[engineguy]

@genxmachining.mill 

Have you tried using your model as "stock solid" in setup??

[daniel_lyall]

You need to post the model there are quite a few things what can make a toolpath fail to do what is needed, we can not help you if you do not help your self, and I take it you are the person from titans of CNC facebook group.

[genxmachining.mill]

Attached model

[genxmachining.mill]

Yes, I modeled a solid prior to the flats and used that as my stock. It reads my top height properly (set to stock top) but does not account for the narrow width near the top.

[daniel_lyall]

It is doing what it is meant to do, I know what you mean as well.

[genxmachining.mill]

After playing around for the past week, I still did not come up with a solution so I manually drew out the width of flat for each level. Highly tedious but it was worth it. Saves 40 mins/part and about 250 inches of air cutting. I've attached a photo of the final toolpaths.

Appreciate all those who took their time to look into it. Cheers!

[rmsmachine]

Have you tried using 3D Adaptive Clearing?  I was able to open your model and set up a tool path using the same step downs and width of cut as what you had in your facing operation and cut the cycle time in half.

Maybe that is not as good as why you came up with but it might be an approach you can use in the future.  The 3d Adaptive is pretty powerful path that has gotten me out of a few tight spots.

In this case the only "special" thing I did was set the rough step down the same as the finishing step down.

[Anonymous]

I will try that out. Thank you very much for your suggestion!