Getting lens form cutter to work in a pocket, not succeeding

[Hydrazine]

I am trying to use an Emuge lens form cutter (from the Emuge tool database on this site) to cut a 5-axis pocket in a part.  The part is basically a thin sheet but curved in X and Y (imagine like you cut a 6" x 6" square out of a car tire).  

I have a pocket in the back (concave) side of the part that is about .05in deep and has full radiused walls.  

I want to use a lens form cutter and basically spiral from the center of the pocket to the outside with a little tilt being introduced to maintain tangency on the cutter face.  I should be able to use a nice large stepover with this method and get a nice finish.  But I just cannot get the tool path to work.

I've read that Morph and Parallel are the only paths to work with circle segment cutters, but 5-axis pocketing says it works with accelerated finishing.  I just can't get it to do what I want.

[crazy^millman]

33 minutes ago, Hydrazine said:

I am trying to use an Emuge lens form cutter (from the Emuge tool database on this site) to cut a 5-axis pocket in a part.  The part is basically a thin sheet but curved in X and Y (imagine like you cut a 6" x 6" square out of a car tire).  

I have a pocket in the back (concave) side of the part that is about .05in deep and has full radiused walls.  

I want to use a lens form cutter and basically spiral from the center of the pocket to the outside with a little tilt being introduced to maintain tangency on the cutter face.  I should be able to use a nice large stepover with this method and get a nice finish.  But I just cannot get the tool path to work.

I've read that Morph and Parallel are the only paths to work with circle segment cutters, but 5-axis pocketing says it works with accelerated finishing.  I just can't get it to do what I want.

 

Without a file to play along at home going to be hard to know which way to point you. Can't share the part you're programming them post up something similar so someone can take a look and see what they can come up with.

Edited September 15, 2021 by crazy^millman
Reread and was thinking Barrel verse Lens Form

[gcode]

There is a new video on the Mastercam You Tube Channel demoing a lens cutter.

I can't access You Tube from work so I can't post a link

[crazy^millman]

7 minutes ago, gcode said:

There is a new video on the Mastercam You Tube Channel demoing a lens cutter.

I can't access You Tube from work so I can't post a link

 

[Chally72]

All 3D HST paths support circle segment/Accelerated Finishing geometry, though of course you won't have much control over the contact point. For multiaxis, a Parallel cut pattern strategy, with a curve selection of the pocket outer extents, and passes set to spiral, should get you a good initial pattern that only leaves the outer pocket fillet/wall to deal with.

To get a lens tool to blend out into a perimeter radius in a pocket, I like to use a Tilt Tool collision control strategy to finish up. See how it affects the final passes on the part in the video below to get the lens tool all the way in the corner fillet even when my side tilt strategy for the rest of the path is calling for a different contact point. As long as your tilt strategy puts the tool reasonably close to the right position, this will tilt into the corner fillets very nicely and you'll be hard pressed to see the transition point.

A file would be the best way forward if you're still having trouble. Hope this helps!