South Bend 9... newbie... help!

I moved the SB9 flat belt slippage question into a new thread.

The South Bend "How To Use A Lathe", like the Atlas "Manual of Lathe Operations", was revised and reprinted several times over the decades. With downloads, it doesn't matter so much - you can always download a different one if you come across it. But if spending good money on a hard copy, try to buy one printed during the years that your particular model was in production. That way, some of the photographs and text has a better chance of showing or pertaining directly to your particular model.

Robert D.
 
I took the tin plate off (guard) and I found the pin on the gear that you release for either a back gear or something else..
I got the motor wired up and turning in the right direction... the manual for the motor says it can turn two ways.? does that mean I can wire the original toggle switch
that came on the lathe to make it turn forwards and reverse? its a just a single phase motor but again it says it can turn two directions..
havent had the motor hooked up since I fixed the wiring... well have to see how the gears work in getting this baby to turn slower.. I hope it works.. it sure is hard to turn threads at 1200rpm

thank you to all whom have chimed in. It is greatly appreciated.. I hope I didnt come off like a jerk who wants all the answers from a post.. and doesnt want to spend money..- I was just frustrated cause
I have spent a pretty penny to get this thing going and Im still not sure where Iam going yet... and $$ right now is tight - and I have a tuition bill due by aug 2 for 3k so $50 for a manual really does have to wait..
thanks to all and keep well.
MM
 
You should be able to wire it up for rev with the existing switch.yes vns

Pull the pin out and engage the backgear to run in backgear mode, rotate by hand to see how it all works.

1200 rpm? The lowest speed should be approx 250rpm (smallest pulley on the spindle and motor).

With money being tight, I'd suggest being a little more resourceful before buying new parts. Most of the $400 already spent, could have been saved by sourcing a used motor or repairing the original and making your own toolpost.
 
I looked at that PDf of "How to Run a Lathe" and it's an ancient version, probably 1920s, and predates your lathe (and mine). I bought a reprint of a later edition which was correct for a 1950s era 9A. Yours is likely from the 1930s. I don't know if there is a reprint that covers your exact model with the single tumbler. I haven't seen one in digital nor hardcopy.

Does your motor pully (and the matching driven pulley) have 2 different grooves? If so, you would have a total of 12 speeds, including back gears.

It's not uncommon for the spindle to be stuck and not release when you pull the backgear pin. Just fille that oil hole with light oil (ATF) and run it a bit with that pin pulled, and it will free up.

The correct oil for spindle and most of the other points is ISO 68, spindle oil, or 20W Non-detergent. for the home machinist almost any light oil will work until you find some spindle oil. I used ATF for years. Just use it generously.

Have fun!
 
Mike,

Basically, all single phase capacitor start AC motors can be made to start and run in either direction. Some do not have the necessary wires to do that brought to the outside world and you have to disassemble the motor and add the wires if you want to be able to reverse it from an external switch. But from what you wrote, yours has the necessary wires brought out.

However, not all ON-OFF switches are capable of being wired for FWD-OFF-REV. Although a custom built switch could actually get by with fewer terminals (such switches are not normally built and would no doubt cost an arm and a leg as they would only be useful for one function), a switch capable of being wired to turn on and off a single phase motor and to run it in either direction will normally have at least 9 terminals to which you can attach wires. If your switch has at least 9, it probably can be so wired. But I have seen Chinese made switches with as many as 16 terminals that could not. If you want to wire your motor for FWD-OFF-REV, post some photos and the make and model number of the switch if US made.

Keep in mind though that if (and I think it does) the SB 9 has a threaded spindle nose, you cannot safely turn, face or thread in reverse.

Also, on the subject of spindle speed, the QCGB has no affect on the spindle RPM. The spindle drives it, not the other way 'round. Spindle RPM changes are affected by either moving the belt(s) to different pulley conbinations or by engaging or disengaging the back gears (if an SB 9 has back gears).

Robert D

MikeManz said:
I took the tin plate off (guard) and I found the pin on the gear that you release for either a back gear or something else..
I got the motor wired up and turning in the right direction... the manual for the motor says it can turn two ways.? does that mean I can wire the original toggle switch
that came on the lathe to make it turn forwards and reverse? its a just a single phase motor but again it says it can turn two directions..
havent had the motor hooked up since I fixed the wiring... will have to see how the gears work in getting this baby to turn slower.. I hope it works.. it sure is hard to turn threads at 1200rpm

thank you to all whom have chimed in. It is greatly appreciated.. I hope I didnt come off like a jerk who wants all the answers from a post.. and doesnt want to spend money..- I was just frustrated cause
I have spent a pretty penny to get this thing going and Im still not sure where Iam going yet... and $$ right now is tight - and I have a tuition bill due by aug 2 for 3k so $50 for a manual really does have to wait..
thanks to all and keep well.
MM
Click to expand...
 
I found the back gears.. I was able to get it to a lower speed.. I understand what you guys mean by using the second pulley on the shaft of the motor.. I will post some pics of the forward reverse on/off switch
I have.. its the original that came with the lathe.. new problem.. its seems as though the lathe is vibrating to the point that threading is bad.. and the threads I am cutting are all chopped up.. its not the tool
I can almost guarantee its the lathe.. maybe my gears are junky? or the surface in the garage is just uneven enough to be a problem... I did my best to make sure its sitting level.. but it seems to "bounce" so as to cause an issue with finish with turning and facing.. and Im using inserts that are new... I will post pics tomorrow.. thanks to all..
 
I use HSS to thread with the back gear ...I'm new to it so I like nice and slow ...Those carbides I think don't like slow and I hav not had good luck with them ....You may need to check your headstock bearings ...but I'd bet it's the carbide.....I am very happy using high speed steel for everything, Also work if sticking out more than a little (use judgement here) needs to be supported with a center or steadyrest or you will likely get the finish you describe
 
rafe said:
I use HSS to thread with the back gear ...I'm new to it so I like nice and slow ...Those carbides I think don't like slow and I hav not had good luck with them ....You may need to check your headstock bearings ...but I'd bet it's the carbide.....I am very happy using high speed steel for everything, Also work if sticking out more than a little (use judgement here) needs to be supported with a center or steadyrest or you will likely get the finish you describe
Click to expand...
+1 good advice.
 
MikeManz said:
I found the back gears.. I was able to get it to a lower speed.. I understand what you guys mean by using the second pulley on the shaft of the motor.. I will post some pics of the forward reverse on/off switch
I have.. its the original that came with the lathe.. new problem.. its seems as though the lathe is vibrating to the point that threading is bad.. and the threads I am cutting are all chopped up.. its not the tool
I can almost guarantee its the lathe.. maybe my gears are junky? or the surface in the garage is just uneven enough to be a problem... I did my best to make sure its sitting level.. but it seems to "bounce" so as to cause an issue with finish with turning and facing.. and Im using inserts that are new... I will post pics tomorrow.. thanks to all..
Click to expand...

I am curious "vibrating / bounce gears junky?" Are you saying the lathe is not sitting flat on the floor? OK, jack up the right tailstock side in the middle of the two legs so it now sits on three legs, its now level. Try it. yes or no? With the belt on high better or worse. Better or worse running with no chuck?
Junky gears =they dont turn fast enough to be out of balance, i think the most gears can do, is to be noisy. Does it vibrate or bounce in back gears?
Mostly vibrations out of balance comes from something spinning fast not slow. bad threading, issues with finish turning, you sure its not chatter? As far as I know at least with my South Bends, they dont like inserts carbide all the new stuff. Kind of like putting high test gas in a Model T. It does no good at all. all I can say the lathe should run like a top. And its just the case of tracking it down like vibrations in a car will drive ya! For some reason I have allways played "second fiddle". Made short, a customer with 1 ton box truck (it went smooth as silk) but the driveshaft center bearing got a little loud, to he had that and a U joint replaced for $xxx bucks. Truck then shook like hell brought it back with no avail. Then it comes here to the problem child. Owner claims they just greased the origional bearing?? We took all apart, examined all and found "the big dollar rate shop" pressed the
center bearing probably with a big socket (on the outside race not on the press point) thus wrecking the bearing. So I charged him 25 bucks plus a
new bearing. Should of came here in the first place. Im trying to say, who knows what has been done to your lathe in the past. So you have to think like a animal MD. Doctor who are the smartest: Like animals and machines, the patients dont talk. With time and thought, you will figure it out. Just
remember it wasnt born with that condition. Please get back with some findings, I am curious, something simple I bet. Sam
 
Carbide likes fast, deep hot cuts, which your SB does NOT like. Stick with high speed steel at least at first.
2nd and more likely is rigidity of your cutter setup. If you are using the original lantern post setup you need the least overhang possible.
Lastly, if using a lantern with carbide, the toolholders usually have a built in rake angle of 15 degrees, sometimes more. Carbide needs zero degrees. There are zero degree toolholders for carbide, but they are rare.

I would also add that not all steel machines alike. Some alloys are exceedingly difficult to machine, especially on older small equipment.
 
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