2D Pocket rest machining incomplete

[mellamanjefe]

I am programming the machining of a bit holder tray. The front has a large pocket to hold loose parts and tools. To achieve this I am using a 1" diameter facing bit to do a rough clearing with the 2D adaptive operation. In this adaptive operation I selected Stock To Leave and set the Radial value to 0.5mm and the vertical to 0mm. My understanding is that this leaves no extra on the bottom of the pocket and 0.5mm around the edges on the vertical walls. The simulation seems to confirm this for me.

To finish the pocket and square off a bit its upper corners I derived a 2D pocket operation from the 2D adaptive. Then selected Rest Machining and entered the diameter of the tool used in the parent operation (25.4mm / 1"). Then I deselected the "Stock To Leave" option to ensure that it pulls the bit up to the edges of the model contours. This is where the computed path does not do what I expect. First it does clear the upper corners from the stock left by the previous tool and in doing so also clears the 0.5 mm of radial stock. But the operation stops there and I cannot figure out what I a missing to make it follow the rest of the pocket's contour around and complete the removal of the 0.5mm in the rest of the edges.

I attach the file and a link to a screencast to hopefully make things clear.

Thanks!

Screencast:

http://autode.sk/2E7tHuZ

[Steinwerks · Accepted solution]

The 2D toolpaths are not stock aware, and so when you turn on Rest Machining it is really only going to clean out corners that the previous tool definition (in the Rest Machining section) cannot reach. In order for this to work after an Adaptive toolpath you would also want to add the minimum radius from that toolpath to the tool diameter since it will leave a cusp otherwise.

Basically the 2D Pocket is not looking at the stock, it's just getting a previous corner condition definition from the Rest Machining tool diameter.

Edit:

What I would suggest is running a 3D Adaptive or 3D Pocket in that boundary with Rest Machining from Previous Operations turned on with a small amount of Radial Stock to Leave, and finish the wall with a 2D Contour.

[mellamanjefe]

@SteinwerksOk, reading your description this makes sense to me now. What I was missing is that there is a difference between what the tool in the Rest Machining operation is UNABLE to clear (the 90 deg corners in this case) and what it is TOLD not to clear (the Stock to Leave). Thank you for the insight, I now see why the results are different than what I expected. I will look into your suggested strategy with the 3D Adaptive to explore that workflow.

As I was working on this while waiting for a reply, I added a derived 2D contour from the 2D pocket which had the effect of completing the work I mistakenly expected the 2D pocket to do.

Thanks!