lathe ????

Trying to get the 10" south bend lathe in our shop tuned up, the clutch that engages the power feed and cross doesnt appear to be working, I took the compound slide off so I could have a look inside the carriage but cant seem to get to the clutch, how do I fix it? Also, our compound slide has some slight front to back slop, looks like the br*** threaded couple under the compound slide might be the culprit (worn causing slop??) does that sound right and if so where can I find replacement parts??? thanks-

 

I suggest checking out the Practical Machinist forum www.practicalmachinist.com. They have a dedicated South Bend forum, and people willing to help.

 

yup great web site dedicated to machine tools , lots of knowledge like here except aimed at machinery .

 

Don't know about 'clutches' on South Bends, but I am wondering if they're like the Atlas/Craftsman and use 'half-nuts' to engage the lead screw?

You have to have the direction selector in one direction or the other to have the lead screw drive the carriage or cross-slide.

Make sure you're not in neutral.

Any chance the South Bend has to be "in gear" to drive the carriage or cross-slide?

It's common for the cross-slide screw - usually an Acme thread - to make the cross-slide travel off the threads.
Going toward the back of the lathe.

A little slop in the cross-slide or carriage is common in older lathes.

 

Thats how it works,if the half nuts are stipped that lathe won't be much good for anything but rough work. You need a new lead screw and half nuts in that case.
Just make sure a bit of swarf hasn't gone into the lever for the half nuts.

 

You might try Lindsay publications they have a nice little booklet they reproduced from southbend called keeping your lathe in trim.They also have a ton of other lathe,machine tool and casting books to help you out. Pool.

 

on my 10L for carriage travel you need:

lead screw turning (lead screw shift lever on head down for forward moving carriage)
1/2 nut lever down
center shift lever in top hole
clutch knob turned clockwise to engage, counterclockwise to release

1/2 nuts are engaged only to cut threads. You don't want to be using them for the everyday moving of the carriage, that's what the clutch is for.

You can deal with a lot of slop in the nut for the cross slide, mine has two turns and it don't matter. But that part is availible, check out PracticalMachinist, there is a supplier on there that sells them.

 

Great answer.
What do you use to make a long right to left - or the opposite - cut when turning something down?

There's a very fine feed selection on my Craftsman Commercial and I use the 3-4 slowest feeds.

Cranking the carriage back is done with the manual feed wheel.

Sometimes I'm envious of lathe owners with the power return gizmo....

 

There should be a reverser ,how else can you cut left hand threads? or return the carriage to a point where you cutting from to ensure accuracy?

 

I think I have all the levers going the proper direction. C9 to answer your question I think the lever can be put in position to move the saddle left to right and vice versa. As far as slop I think I can live with it, just make sure cross slide is back towards me when I start cutting (my craftsman lathe at home has the same slop, it doesnt however have a power feed, just the half nuts - glad I learned your not supposed to use the half nuts for a power feed, I had been doing that) the SB is the first lathe I've used with a power feed. On the SB I can get the lead screw engaged in either direction and the half nuts seem to engage just fine. My clutch doesnt have a knob like the lathes I've seen in pics on the net. Instead it has a lever that you pull up or push down, the clutch just doesnt seem to be engaging? I do have the SB lathe book and the How to keep your lathe in trim manual as well - havent found anything in the books about adjusting/maintaining the clutch???
On a seperate note, what has made this an issue is I have a number of students using the lathe. I have a hand full of kids who are messing around with those little knock-offs of the old Honda 50cc engine. These kids have been putting big bore 110cc kits on these motors and doing all sorts of trick stuff. Theyve had to take the main shafts out of these engines and turn them down to fit in the 50cc cases - they are doing some pretty neat hot roddy stuff with these little things...the hot rod bug is pretty safe with some of our mechanics of the future, have faith! thanks-

 

C9, you asking me?

The lead screw gear shift on the head has for., rev., and neutral. So you can send the carridge either way under power.
Same with the cross head, you reverse the leadscrew to go the other way.
I normally cut under power and wind back by hand unless I need to cut my way back.

DirtyNails, When thread cutting sometimes I back the tool out a little and then reverse the whole lathe to get back to start, with short lenghts of thread.
On long threads, you withdraw the tool and shut off the lathe, then wind the carridge back by hand and pick up the next cut with the thread indicator dial that's bolted to the right end of the carridge. It has a dial which indexes the lead screw to the spindle to get the tool in the right spot for the thread. some kinda of magic.
And yeah, You can do left threads by running the leadscrew in rev and the spindle forward.

 

Look on Ebay for a reprint copy of the Southbend manual, "How To Run A Lathe". These are kind of the 'Bible' of running a lathe. And for sure, visit the SB forum on Practical Machinist - the members there are as knowledgable and helpful on machine tools as are the HAMB members on hotrods.

 

Go to this site and post in the south bend lathe section they can help you out.

http://www.practicalmachinist.com/vb/index.php

 

mines a 1953 SB 13" and you have forw, N and rev up on the head and when the lever on the cairage is in neut(center). you can engage the clutch by turnung the knob. the Half nuts will not engage if the clutch is engaged and vice e vers e hope that helps