Optirough/rest insists on ramping into the part

[JB7280]

I've tried changing nearly every setting, and boundary I can think of, and no matter what I do, Optirough wants to ramp down into the part.  I've moved on, and started creating my own dynamic toolpaths instead, but what gives?

 

[Chally72]

To enter from air while using a stock model, you must give Optirough a containment boundary that includes the air to enter from. If you're using Silhouette Boundary in Toolpath Control, which it looks like you are, change the Compensate To strategy to Outside, and add 2" into the offset value, just to give it a bigger boundary area to search for air to enter from. Instead of using Silhouette Boundary, I commonly just do something like draw a big wireframe circle that encompasses my stock and part and then select that as a containment. 

 

Now, the next common entry problem with Optirough is it likes to cut holes and pockets first, and side mill second, which is the exact opposite of how I like to approach parts. For that, we can use the Skip All Pockets choice in Toolpath Control that was added for Mastercam 2021 to basically tell the path to side cut only, and never try to enter with a helix or ramp. Before 2021, even with playing around with a skip pocket size, Optirough was pretty ambitious in trying to ramp into tiny areas even when a helix didn't fit or you didn't want it to go there.

 

Here's a good video on Optirough flow in 2021 where we're concerned about entries:

 

[JB7280]

I actually tried using the large wireframe rectangles you see as the containment boundary, which are well outside of the part, but the key seemed to be in just telling it to skip the pockets smaller than _____.  There is a very shallow rectangle shaped pocket that it was trying to cut first.    I will check out that video this evening.  Thank you!

[Chally72]

The trick I used in 2020 and earlier to ensure that there was NEVER a ramp entry anywhere even if it somehow found a loophole in my Skip Pockets Smaller Than setting was to set my entry method to Medial and give the additional slot width some large value like 10". I know this method seems goofy, but when you leave the entry method at Helix, Mastercam will actually go back and try to do a ramp if the helix fails because it'd be too large: