clipping a thread

[91blackbird]

Need some help. Do all my threading on a G92, does anyone know an easy way to do a clip? Controls are Fanuc 21i-tb, on a l&l45-80 lathe. Thanks.

[cogsman1]

What is "Clipping a thread"?

[neilw20]

What is "Clipping a thread"?

[Geof]

Originally Posted by neilw20 What is "Clipping a thread"?

Different name for a Higbee cut?? An abrupt start that takes away the feather edge at the beginning of a thread.

[neilw20]

Thanks Geof.
Never too old to learn a new name.

[chucker]

Try the link below I ran across it the other day talks about using a G32 to do the higbee cut

http://www.cnczone.com/vb.../t-121785.html

[g-codeguy]

Blackbird, I thank you for the question, and thanks to the others for their replies. I learned something new today...always a pleasure. Now I will have to give it a try myself. We do lots of threading, but never had a call for this type of thread.

[brtlatjgt]

Can use same thread cycle. Just move your start point over 1/2 lead and shorten thread length. You can actually use a regular turning tool or I like to use grooving insert for the thread cycle on the higbee.

[91blackbird]

Thanks for the replies. We ended up using a groving tool to do it. Worked not to bad. I will look into a G32 to see if it will work. Moving the thread over 1/2 a pitch was what I wanted to do, but we weren't sure that was what the blueprint called for.

[g-codeguy]

Originally Posted by 91blackbird Thanks for the replies. We ended up using a groving tool to do it. Worked not to bad. I will look into a G32 to see if it will work. Moving the thread over 1/2 a pitch was what I wanted to do, but we weren't sure that was what the blueprint called for.

Mind telliing me what RPM you used? I tried it on a thread running at S1500 and it took 3/4 of a turn to pull out. Not acceptable! It seems to me that this would work only at very low RPMs. Rapid on our Daewoo is pretty fast. Fast enough that I always flip the switch to 50% for manually moving the turret.

Thanks.

[91blackbird]

I think the rpm we used was 200, same speed as threading.

[littlerobb]

All turning centers are going to rapid at different ipm's depending on year, make, model. I find that 50 rpm is good because You can offset your grooving tool on the X axis and it is turning slow enough that you can watch where it is on the Z axis and make your adjustments there.

Or if you aare just backing the start position off half the pitch, keep in mind that regardless of what the Z offset may be on the grooving tool it must be exactly the same as the threading tool, doing this makes a more repreatable program, just inform your operators.