Avoiding "Rapid collision with stock"

[kevinGG4T7]

I was wondering if someone could take a look at this for me? No matter what I try I cannot avoid getting “Rapid collision with stock errors” in the Simulation when it runs the Parallel toolpath. I've tried everything I know how to do to prevent this, but I'm out of ideas. The only tool path that I can get to work is Geodesic, but this isn't really the toolpath I'd like as it's too complicated and would run for 8 hours.

What am I doing wrong? I’ve been at this for hours and I’m just going around in circles, so a fresh pair of eyes would be much appreciated. Is there a way to prevent these errors when running the Parallel toothpath?

[Ringarn67]

Bottom of dune to bottom of stock is 0.25 in!
Axial Stock to leave in 2D countour2 is 0.5in.
Tool in Parallel2 has "permission" to go outside model as long as it touches upper surface of model.
And in bottom left corner, as in other places, 2D Contour is "above" bottom of dune.

Solution 1, Thicker Stock
Solution 2, Much lower Axial Stock to Leave (like 0.05in)
Solution 3, set Tool boundary to "Tool center on boundary" together with Little lower Axial Stock to Leave (like 0.24in)

Also, Vertical Lead-in is only 0.1, so tool go straight down to material left from Pocket, change it to 0.75in

Nice design btw, I will study it and learn a lot, as I have no experience what so ever of surfaces

[seth.madore]

The finishing toolpaths have very little knowledge and control over what stock is there and how to navigate around it. The easiest things to do are:

1: Leave less stock with 2D toolpaths

2: Increase the Vertical Lead-in radius to a much larger value. In your file, I found that a 1" value would do the job (although smaller would work)

 

[kevinGG4T7]

Thanks so much for taking a look. I'll try those ideas. 

Thanks for the complement about the design. I wish I could take credit for the concept, but Kristian Laholm is the genius behind the idea, in his video https://www.youtube.com/watch?v=ltqmIIbAoVE&t=718s

Cheers

[kevinGG4T7]

Hope this is helpful to others:

No matter what I did I just could not get the parallel toolpath to stop giving Rapid collision errors. I was tempted to run the file anyway, and hope ofr the best.

However, thanks to some suggestions by others, I got it working by switching to a Scallop toolpath and setting the lead-ins to 1". 

I'll start the milling in the morning and hopefully all will be well!