anyone else undercutting?

[rsbeadle]

I am having great success with the new undercutting abilities of V9. I have hade some lolipop tools special made to cut about .080 under surfaces to finish parts 100% on cnc with a three axis machines. The only problem is the long processing time. I have come across an insert tool that will cut about .125 under but I have to define it as a slotmill (.600 flute w/.060R). This definition causes the process time to go through the roof (1.5 to 2 hrs for a 1 meg nci file). Anyone defining tools differently to speed up processing time?

[Mike Whitten CAD/CAM Contractors]

Can you just flowline it?

 

Many times, depending on the situation, it will be much better to just create a nice new single coons patch and flowline it.

 

Mike

[rsbeadle]

I have to protect the surfaces above the undercut. I haven't tried flowline. I have been using rough contour. The output has always been correct with contour. I have tried rough pocket with the lolipop tool but it sometimes retracts through the upper surface causing a gouge. I can't remember if flowline is supported with undercut. I'll look into it. One problem with flowline is that all the surfaces need to flow in the same direction. I am using geometry with multiple surfaces. Think of a square boss 2 inches tall, 1 across from 1.5 up and .875 across down from 1.5. I have to cut all the way around the boss while protecting the top and other surfaces around the sides and bottom. (extrusion hollow die). Thanks

[Mike Whitten CAD/CAM Contractors]

Steve,

 

I have had similar problems as you have descibed when I tried undercutting a few times. To undercut with flowline, all you do is turn off the "check flowline motion for gouge" in the flowline parameters and depending on the part you must turn off "check gap motion for gouge" in the gap settings. So, used care to check for gouging. The big trick is the surfaces. As long as they are nice the flowline works perfectly.

 

I am not an expert, this is just what has worked for me in the past.

 

Thanks,

Mike