Clausing 6329 Metric Threading?

[Shootymacshootface]

I have been wondering if there are any gears in existence that would allow this lathe to cut metric threads.
Any thoughts?

 

[Rootpass]

Harold Hall has a book detailing metric threading on an imperial machine. Basically saying that if you use the closest imp thread to the metric you want that the difference is so small as to not be a problem. I believe it’s in Metal Workers Data Book.

 

[Shootymacshootface]

Thanks for the info. My experience has been that no common hardware is interchangeable, but I had never had access to a machine that could cut so many different threads. Yet, another creative way of seeing things in the world of machining.
Thanks!

 

[mickri]

I know nothing about a Clausing 6329 lathe. So I can only give you a general idea of what to do to cut metric threads. There are threads about how to do this on Craftsman lathes. Cutting Metric Threads Through A Qcgb On A Craftsman 12x36 | The Hobby-Machinist (hobby-machinist.com) It involves some math to figure out what threads can be cut. Halligan142 has a video on how to do it on a South Bend lathe. On the Craftsman 12x36 with a QCGB you replace a 48 tooth idler gear with a 52/44 combo gear to be able to cut the common metric threads. I did this modification on my lathe. It is handy to be able to cut metric threads.

Hope this helps you out.

 

[Shootymacshootface]

I know nothing about a Clausing 6329 lathe. So I can only give you a general idea of what to do to cut metric threads. There are threads about how to do this on Craftsman lathes. Cutting Metric Threads Through A Qcgb On A Craftsman 12x36 | The Hobby-Machinist (hobby-machinist.com) It involves some math to figure out what threads can be cut. Halligan142 has a video on how to do it on a South Bend lathe. On the Craftsman 12x36 with a QCGB you replace a 48 tooth idler gear with a 52/44 combo gear to be able to cut the common metric threads. I did this modification on my lathe. It is handy to be able to cut metric threads.

Hope this helps you out.

Thank you!

 

[wa5cab]

Simply using the nearest inch pitch thread to the metric pitch that you want may or may not work. And in general will not work for making a metric lead screw. It all depends upon two things. First, the selection of inch threads offered by your machine. And second, how long or thick the female metric thread is.

A guy in South Africa figured out how to do it pretty well for any of the QCGB equipped Atlas or Atlas-Craftsman machines. "pretty well" being defined as the actual pitch being cut measured in inches being correct to at least 3 decimal points. Whether the same approach could be made to work with the 6300 Series or not I don;t know, but don't think so as the Atlas boxes cut all threads except for the coarsest few with the Sliding gear IN. And the inch or metric metric conversion was selected by the sliding gear at the expense of not being able to cut 4.0 through 7.5 TPI. . Whereas the 6300 box cuts half of the available TPI with the sliding gear IN and the other half with it OUT.

Clausing at one time offered "metric conversion kits" for at least some of their inch-based machines. Unfortunately, the few instruction manuals that we have copies of don't include the 6300. I would recommend that you call Clausing next week and ask them what was at one time available. And assuming that there was one made for the 6300, see whether or not they still have the drawings for any parts that were in the kit, plus a copy of the instructions that came with the kit. Ask for either Tom or Ron McNett. Phone # is 800-323-0972. And let us know what you learn.

 

[Shootymacshootface]

Simply using the nearest inch pitch thread to the metric pitch that you want may or may not work. And in general will not work for making a metric lead screw. It all depends upon two things. First, the selection of inch threads offered by your machine. And second, how long or thick the female metric thread is.

A guy in South Africa figured out how to do it pretty well for any of the QCGB equipped Atlas or Atlas-Craftsman machines. "pretty well" being defined as the actual pitch being cut measured in inches being correct to at least 3 decimal points. Whether the same approach could be made to work with the 6300 Series or not I don;t know, but don't think so as the Atlas boxes cut all threads except for the coarsest few with the Sliding gear IN. And the inch or metric metric conversion was selected by the sliding gear at the expense of not being able to cut 4.0 through 7.5 TPI. . Whereas the 6300 box cuts half of the available TPI with the sliding gear IN and the other half with it OUT.

Clausing at one time offered "metric conversion kits" for at least some of their inch-based machines. Unfortunately, the few instruction manuals that we have copies of don't include the 6300. I would recommend that you call Clausing next week and ask them what was at one time available. And assuming that there was one made for the 6300, see whether or not they still have the drawings for any parts that were in the kit, plus a copy of the instructions that came with the kit. Ask for either Tom or Ron McNett. Phone # is 800-323-0972. And let us know what you learn.

Thank you.
I have spoken with those folks before regarding my mill. They still have a surprisingly good about of parts for long out of production machines. If I could get my hands on some drawings, that would be amazing.
John

 

[Nutfarmer]

The 6300 doesn't use change gears. I don't see any way to fit a metric transposing set on it. All threading changes are made with a three stage quick change box that runs in oil.

 

[Shootymacshootface]

The 6300 doesn't use change gears. I don't see any way to fit a metric transposing set on it. All threading changes are made with a three stage quick change box that runs in oil.

That doesn't surprise me at all after seeing how the cover is bolted on. Its not very easy to remove.
I will compare imperial and metric pitches, take some notes and do a little experimenting.
Lathes are so awesome!
Thanks!