Chasing Threads Help needed

[mholden]

If you are using an newer Milltronics lathe you can use the tread chasing cycle. see the attached doc. (I had to zip it to get it to upload)
Milltronics offers a program for thead chasing that you can change the depth of cut as well but there is a charge for it.

[Farmers Machine]

I forgot to say the part was about 4" OD and the thread was only like 3/4" long. It has some thread relief but stops at a shoulder. I am using a Milltronics ML20 lathe with Pragatti turret so there is no way to adjust a compound. The lathe is also equiped with conventional induction spindle motor so it does not have spindle orient capabilities. I think an adjustable tool holder is a great Idea it would be easy to adjust it in to match, it just has to be ridjid, easy to adjust, and lockable. and there would have to be some sort of set up program run to sync the spindle to the part, and then adjust the tool into the thread. Thank you, The Farmer.

[HuFlungDung]

Perhaps thread milling might be another thing to try. This would be like a "slow-mo" version of thread chasing. I suppose the advantage would be that 'synchronization' of the thread mill can be easily accomplished with simple commands, and not the cross threading hazard associated with live threading on a lathe spindle.

I suppose chances are good that the whole batch of parts may actually be very uniform in the phase angle of the thread start, if they were all originally run on one machine. The trick would be to have good locating surfaces elsewhere on the part.

[LJ48]

I think HuFlumgDung might have an idea. If you have a Optical comparator you might be able to layout part and thread mill and set depth of mill to match part. Not sure how to get it to run in metric though.

LJ48

[jpawelk]

What type of lathe are you doing the threading on? CNC or manual? If it is a cnc machine (and with proper software and manual operation) you can chase threads with ease. Let me know if you need any assistance.

[Farmers Machine]

It is CNC with handwheels and remote hand wheel atachment. What kind of soft ware would I have to have to Catch lead and repeat 3 or 4 passes to get to depth and gauge properly. Thank you for any Info. The Farmer.

[jpawelk]

Please refer to the zipped file that mholden had posted earlier in this forum. The thread chasing cycle is a one pass operation. Your machine will not be able to chase threads in multiple passes due to it not having spindle orient. The cycle is an automatic cycle where you enter all the data in one conversational page and then handwheel the threading insert into a known good thread and then hit enter and the spindle will then turn on and the machine will make a on shot thread repair. Hope this helps