Need Help!- CITIZEN A20 LINK THREADING

[glenn105]

We are new to using a Citizen A20 Swiss Style Screw Machine and are working with a job that requires LINK THREADING. Our question is as follows:

What would be your suggestions for best results LINK THREADING a 1/4"-28 2A stud that requires 2-1/2" of thread? (We are threading 304 and 316 Stainless Steel)

1) RPM: we are currently running 600 RPM.
2) INSERTS: we are using SECO 16ERAG CP500 R/H
3) We are picking up on the thread back 2 full threads.

THANKS GUYS!
-Glenn

[ProProcess]

Originally Posted by glenn105 ... LINK THREADING...

What is "LINK THREADING"?

[Tcooper571]

I have run a few Citizen A20's in the past and am a bit confused by what you mean about "Link Threading", I am assuming you mean turn, thread, turn, thread? If so WINCNC which is an editor software specifically for Citizen Machines that has this programming option built into the software and will write the complete section of program for you. All you need to to is fill in some basic info and away you go.

You can even download a free 30 day trial at http://www.marucit.com/products/index.html. Then if you choose to keep it you purchase it at the same website after your trial. I highly recommend trying this software for anyone that has a Citizen. Good Luck.

[ProProcess]

Originally Posted by Tcooper571 ...WINCNC which is an editor software specifically for Citizen Machines ... I highly recommend trying this software for anyone that has a Citizen. ...

I second that!!

[glenn105]

Thanks for the tips, guys... We've seen WINCNC, but have not used it yet. Probably will give it a try.

FYI - "LINK THREADING" is threading a section of the workpiece and then moving the workpiece or picking it up in the sub-spindle and then coming back at the piece to continue the thread to produce a longer threaded section.

Still looking for some suggestions on RPMS etc.

thanks,
-Glenn

[ProProcess]

Originally Posted by glenn105 ... FYI - "LINK THREADING" is threading a section of the workpiece and then moving the workpiece or picking it up in the sub-spindle and then coming back at the piece to continue the thread to produce a longer threaded section. ...

Are you still attached to the bar and supporting with the sub.
Or ...
Are you cutting off and blending the threrad with back working tools?

Originally Posted by glenn105 ... Still looking for some suggestions on RPMS etc. ...

I would first suggest that you contact SECO for a recommendations.
They would be able to give specific information about the grade and how to apply it in the material you are using.


You have not really said, are you having a specific problem?

[glenn105]

We are working between spindles. Workpiece is being held by both the main and sub.
Because of the length of the part, we need to thread in sections. We have played with a few different RPMS, but just not sure how fast we can push it using the SECO Inserts.
We can't seem to find any suggested settings for these particular inserts. One thing we like about Ingersoll tools and some others is that they suggested settings are printed on the packaging. (SFM)
THANKS!
-Glenn

[ProProcess]

Originally Posted by glenn105 ... We have played with a few different RPMS, but just not sure how fast we can push it using the SECO Inserts. We can't seem to find any suggested settings for these particular inserts. ...

Have you tried this "Thread Turning Wizzard" from the SECO website.
I have not tried it, but I found it quite quickly with Google.
Good luck!
Let us know how it works.

[citizencnc]

Check this out.

YouTube- CNC Citizen L32 making a part

YouTube- CNC Citizen L32 making a part

[ProProcess]

Originally Posted by citizencnc Check this out. YouTube- CNC Citizen L32 making a part

That is indeed a long thread, though I would not recommend processing a thread in this manner, especially under the original poster's conditions.
Threading the stock diameter with a swiss machine is just asking for trouble.
The video is in Brass and you may be able to get away with doing this.
The issue is that when you thread, you inevitably produce a burr (all be it small) on the OD.
This burr in Brass can be sheared off as it retracts in the guide bushing (you can hear it in the video).
In 304 or 316 SS you will likely get "stuck" in the guide bushing causing the material to "slip" in the main spindle which will cause disaster to ensue.