Got my lathe powered on, trying to understand my apron controls

twooldvolvos

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I finally turned my South Bend 10K on after clearing it out a permanent spot and running power in my basement. Before the chips fly, I am becoming comfortable with the lathe features. The one I need the most help with at the moment is the apron controls, specifically the purposes of the half-nut lever, the feed change lever, and the clutch.

I understand that if feed change lever is engaged, I should be able to use the clutch to start and stop the feeding. Mine will not stop when the clutch wheel is all the way CCW. Is this correct?

Also, I understand that the clutch does nothing if the half-nut lever is engaged. Is this correct?

Lastly, is it safe to engage the half-nut and the feed change levers lathePluggedIn.JPGwhen the lead screw is turning?

Thanks to everyone for your help.
 
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With the "star" clutch knob fully ccw the carriage (or cross feed) should not move. If it does no matter where you set it, there is something wrong-
It might be broken or bound up somehow. A very reliable system but does require attention about every half-century or so.

The half nut lever is typically used mostly for cutting threads where you want a precise increment of carriage movement per revolution of the leadscrew, however you can use it for feeding if you like, but there is more risk of damage if you "crash" the carriage or tool into the chuck as opposed to using the feed clutch mechanism. The feed clutch is designed to slip whereas the half-nuts won't.

It's been a while since I ran a Southie but I think that's basically accurate info
-Mark
 
Oh I've been there. I had a SB 13. Lots of fun you'll have.
John is right as usual.

I believe this is it or you may find a free PDF somewhere...

 
Great looking machine. I have the bench version.
On mine, with the clutch all the way CCW the carriage does not move.
It's perfectly fine and necessary to engage the half-nut lever while the lead screw is moving.
I never change the levers while the lead screw is moving.

This screenshot is from the 55th edition of How to run a lathe:
View attachment 344464

David,

Thanks for your reply.

I just did a test.

Feed change lever: up (longitudinal)
Lead screw: engaged down (forward)
Clutch: all the way CCW
Half nut lever: down (off)

When I turned the clutch CW, the apron moved to the right as expected. Looks like it works after all!

Dan
 
The controls are interlocked.

The 3 position lever-like arm selects which drive to use and if in cross feed the 1/2 nut will not go in.

The SB books have good detail on the lathe, the sears manual even more.

Sent from my SAMSUNG-SM-G930A using Tapatalk
 
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