# Clausing 6300 Threading Chart Help



## pc620 (May 6, 2021)

I just found and joined this forum. I finally bought my very first lathe a month ago (always wanted one) - had to do a lot of cleaning-ups. I have been reading many threads related to thread cutting chart but still cannot find specifics to my lathe as the charts are different. I don't know how to read the chart (see attached photo).

Say if I want to cut a 5/8-11 thread, how do I set up the lathe:
1) Sliding Gear In
2) Set Gear Shifter Knob to the LEFT (I think)
3) What's next?
4) How do I read the table to the right where it says "Decimal figures are long feeds"? What does this mean?

Thanks in advance for the response.


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## mmcmdl (May 6, 2021)

Long as in longitudinal .


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## pc620 (May 6, 2021)

mmcmdl said:


> Long as in longitudinal .


Thank you. Now I know what it is but still don't understand what each number on this table indicates. For instance, what does the number 7 mean?


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## mmcmdl (May 6, 2021)

You have a chart with threads per inch and feed rates per revolution . Cross feed is equal to 1/4 of the longitudinal feed . It's only one chart so there isn't a left or right side . For instance the 7 equals 7 threads per inch .


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## mmcmdl (May 6, 2021)

BTW welcome to the site and ask as many questions as you need . All members are friendly  on here ( Most of the time )


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## Shootymacshootface (May 6, 2021)

On the left side of the gearbox there is the sliding gear, which would be on tbe upper left if viewed from the spindle end. And tbe gear selector on the lower right. With the gear disengaged (the lever on the front that moves up and down) push or pull the gear selector so that the desired row is highlighted on the chart. Then have the other controlls in the positions that are designated on the chart. That will get you the desired thread pitch witb the lead screw. The decimal numbers are what you get for movement per revolution when using the carriage feed and not the lead screw.
I have a 6329, feel free to ask if you aren't sure about something.


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## pc620 (May 6, 2021)

Thanks for the reply. I have a little better understanding now but still unclear of something.
I am attaching another photo for this discussion. To achieve 11 pitch thread, pushed gear sliding IN, I highlighted the position of the the gear selector (see photo) and set the gear shifter to the Left position. Is this the correct setup needed to get 11 pitch thread?

Update 1:
I just did a slight cut test and I think I know how to read the chart now. Thank you much for the help. *My next question is, does it matter when you engage the half nut (1, 2, 3 or 4) as long you re-engage it at the same number?*

Update 2: 
Just watched YT video by Joe Piecznski on the thread chaser gauge usage. Very good video and got my question above answered.


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## mmcmdl (May 6, 2021)

Yes it is . If you're just getting started , you can make a light cut by hand and check the pitch to make sure . Just engage the leadscrew and turn chuck by hand after setting all handles etc .


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## Shootymacshootface (May 7, 2021)

Yes, I think you get it. Just to be sure, this is what everything should look like for an 11 TPI thread.


Why does your window not have that red bar behind it? Or am I just not seeing it? 
Here is some more info about using the thread dial, and a chart for the carriage feeds.


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## pc620 (May 7, 2021)

Thanks much for sharing the instructions - I am saving them now and will review them closely as soon I get a chance. My lathe is not equipped with variable drive but I am using VFD for speed control.


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## Shootymacshootface (May 7, 2021)

The drive is just a convenience. When you are threading you will want to start off slow 75 rpms or so.


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## pc620 (May 7, 2021)

Shootymacshootface said:


> The drive is just a convenience. When you are threading you will want to start off slow 75 rpms or so.


Will keep this in mind. Thank you.


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