90 DEG THREAD RUNOUT

[HEAVY METAL]

How can I create a straight 90 run out at the start of a thread. the straight move must follow the pitch dia. I am using the threadmill toolpath but when i use the entry/exit line length it does not move in Z along the thread pitch I am programming in the xy top plane and using a special thread form cutter. I tried creating the helix geo and using that and a contour toolpath but it wont work with compensation.

[john316]

.

 

Does your machine controller accept helical moves? The lead-in with helical should take care of it.

 

.

[John Summers]

This looks like a roll/unroll problem that hasn't really been addressed. Let's assume that you're geometry is unrolled (a straight line). Roll it up, and add straight entry and exit lines. Then unroll it. Now the entry/exit lines are curved in the unrolled domain. Or you could just add the lines to the already flat helix to keep from breaking it up.

[HEAVY METAL]

what toolpath should i use the threadmill path or 3d contour . the 3d path works if I set the compensation type to off. I created the hekix and the used trim extend on the ends at the gace me the 90 deg runouts following the pitch. I would like to have compensation on so i can step cutter over. do i need to scale my helix

[HEAVY METAL]

the run outs are not a arc move but a straight move in along the y with the z moving with the thread pitch

[John Summers]

I'm not sure I understand your part thoroughly. Maybe you could send me a part file. I don't think you want to scale a helix. The curve I was talking about would result from unrolling a straight line entry/exit line.

[John Summers]

After looking at the part, scaling the helix does make sense. The helix axis is on Z, so scaling it in X,Y but not Z would give the right kind of offset. So would 'offset contour'.