Lathe - Switch/Wiring



Drum Switch (Feb 9, 2001) Asbestos & Old Switches (May 26, 2003)
Spindle Forward Reverse switch (Mar 19, 2001) Wiring motor to reversing drum switch (Jun 5, 2003)
Wiring diagram (Sep 3, 2001) Cutler hammer drum switch (Oct 8, 2003)
Automatic Starter switch 13" SB help (Jul 29, 2001) 9C workshop forward/reverse switch (Nov 16, 2003)
1953 South Bend Wiring (Sep 21, 2002) Electrical switch heavy 10 (Jan 27, 2004)
Forward/reverse switch wiring diagram (Dec 2, 2002) Cutler-hammer drum switch wiring (Feb 29, 2004)
Reverse switch (Jan 19, 2003) Drum Switch Wiring (Jun 12, 2004)
What's this switch for? (May 1, 2003) Furnas Reversing switch HP1 style R1A 220VAC wiring (Dec 30, 2004)
SB 9 motor Switch Diagram (May 8, 2003)  
Drum Switch
I have just gotten a 9" Model C South Bend lathe. The info from this group has already provided a great deal of help to me. I have been setting my lathe up for my particular needs, and I have a question: I have a Furnas Forward Off Reverse Drum Switch, but the switch is only wired for reverse. My Baldor motor says it is capable of being reversed. What would be the typical wiring schematic for a forward AND REVERSE setup on my lathe? Or does anybody know where to find out more info on this? Or is this not advisable due to the fact that the chuck might back itself off the spindle? Thoughts and opinions anyone? Also, I am missing a threading dial. Would it be possible to make one, if I was able to find out how many teeth are on the thread dial gear that engage w/ the lead screw? Does anybody know how many teeth there are? Frank (202)
Frank, Reversing is not real useful (at least for me on my 9" SB). And yes, the chuck on my SB will unscrew if I'm not careful about high-acceleration reverse. If you only have reverse right now, either your switch/motor may be wired wrong or the switch/wires broken. The Baldor motor should have instructions on the label on swapping the start winding wires in order to reverse the motor (so it will go forward in your case). BTW, Baldor is a very good brand! There is a nice article in "PROJECTS Three" the Home Shop Machinist book about setting up motors and reversing switches. I also recall an article in one of those books about making your own threading dial for a SB. I'll track down both articles and see if I can put 'em up on the web if you can't get them else where. I don't have a scanner so I thought I might try faxing it to myself. Paul R. (203)
Frank, There are a couple of reasons for having a reversible motor on your lathe. Grinding, spring winding, backing out taps and dies from the work, and left hand tapping are the most common. Chucks on threaded spindles do have the nasty habit of unthreading but in all the work I have done, I only once did I have a chuck loosen up on me. Others will tell you about bouncing a chuck down the bed and across the shop but this usually happens only if the chuck wasn't set and/or the spindle is operated at high RPM and then stopped suddenly or reversed (instant reversing motors). Baldor motors are generally good motors. Is it a single phase or three phase motor? Three phase hook-up is straight forward. Single phase will depend on whether your motor is to be wired for 115V or 230V operation. If you haven't decided which, I will recommend 230V. First of all, you will have to identify the leads coming out of the motor. They should have metal tags (old) or white inked (later) numbers on the leads like T1, T2, etc. A single phase dual voltage reversible motor should have: T1, T2, T3, T4, T5, and T8. They are: T1, T2, T3, T4 - Run winding leads, T5, T8 - Start winding leads. For 115V operation, the leads should be wired: T1 + T3 - L1 (Line input) T2 + T4 - L2 (Line input) T5 and T8 are wired to L1 and L2 and to reverse the motor, you reverse T5 and T8 in respects to L1 and L2 For 230V operation, the leads should be wired: T1 - L1 T4 - L2 T2 + T3 + T5 - (just wire nut these together) T8 - L1 or L2 (depending on the motor rotation you want) Now I cannot be sure of which model of Furnas drum switch you have. If it is like most of the ones I see, when you take the cover off there will be nine terminals arranged in three sets of three. There will be three jumpers connecting the three terminals at one side to the terminals on the other side. Two jumpers criss-cross and one is a straight through. If it is like the one I mentioned, then wiring for 230V single phase is easy. Send mean e-mail and I'll send you a wiring diagram. If you have a different style of drum switch, there may be a wiring diagram on the underside of the drum switch cover. From that, you should be able to wire up your motor. Webb (204)
Frank, I posted a wiring diagram for your reference. Webb (205)
The Home Shop Machinist May June issue 2000 has an article on how to make a thread dial for a lathe and the information can be used to make one for a SB 9". Ed (206)
WOW!! I couldn't believe all of the help you guys gave me! I rewired my lathe today and everything works GREAT including reverse. Thank you, wyman100 for your detailed instructions. They helped tremendously! Does anyone happen to have a copy of the tread dial article? I could pay postage and copy costs. I just finished turning down some bushings for an English Wheel that I am helping my father build. Frank (207)
Frank, I found the "Projects" volume that has the threading dial project for a 9" SB. Send me your U.S. mail address and I'll send you a copy. I was going to get someone to scan it in for me, but that would take a while. Paul R. (208)
Frank, I have the article on the thread dial making send me your address and I will get it off to you Ed (209)
Frank, I have posted a wiring diagram for a Furnas Drum Switch for 115 volt operation. Webb (211)
Spindle Forward Reverse switch
A while back I bought a 9" Model A mounted on a metal cabinet stand with the underneath drive unit. I am just now starting to get it cleaned up and running. My question is whether or not my Forward/Reverse switch is wired correctly. When in Forward, the spindle (Looking at it from the tailstock) turns in the Clockwise direction. This seems backward to me. When going forward, shouldn't it spin in the counter clockwise direction so the cutting is done on the top edge of the tool bit? Mike (347)
Mike, Yup, sounds backwards. Paul R. (348)
Wiring diagram
I have a1/2hp motor, it has 4 stud w/nut terminals. The control switch mounts on a gear cover of the headstock. This switch is "forward-0-reverse" (left to right). Inside the switch box are 3 rows of 3 terminals, the left and right sides are connected by several soldered in jumper wires (factory done)? How does all of this go together. David (1443)
David, you're going to have to supply more information and even then it is going to be difficult for any one to give you accurate and reliable instructions. Is this motor a 120240 VA. model or a straight 120VAC? I can tell you this though. The direction the motor is turning is determined by the start winding which is two wires. The start winding is connected in parallel with the run winding. This winding is switched out of the circuit by a centrifugal switch when the motor gets up to run speed. The motor is reversed by swapping polarity of the start winding with respect to the run winding. The fact that you have only 4 terminal studs on the motor leads me to believe it's a 120VAC model only. An Ohmmeter would be useful here to determine you wire pairs. It may be helpful to contact the manufacturer of the motor for wiring instructions. Did you look on the motor access plate to see if there is any information there? Chris (1448)
Automatic Starter switch 13" SB help
I have a 13" 1939 model High School Classic. Went to use it the other day, nothing happened, after some trouble shooting I determined that the automatic starter switch was not working. I have a lever for off, forward and reverse; (I call it a railroad switch?) and a start and stop button mounted over the lathe. It worked fine for about a year, then yesterday nothing. Determined the stop start buttons were making contact OK. So went to the relay box and sure enough the coil that snaps the switch closed when you press the start button and then open when you press stop was not doing anything. It has voltage to one side of this coil, nothing on the other terminal, so seems like the coil is bad. Further research in the cover of the box reveals replacements parts list to include an "operating coil", the coil has a part no. on it, 69A113, 208v 60 cycle. Any advice will be appreciated, will head to www to find Allen-Bradley for replacement part and try that, less someone in our group has an idea. In the interim have wedged a piece of wood to hold the relay in closed position and used the lathe most of the afternoon yesterday & nothing smelled bad, so assume I am OK, but think I am probably overriding the relay kick-out feature? Big tom (1212)
Tom, are you running single or three phase? My 13" has a single phase motor and doesn't have a starter/ contactor. I just have the forward/ off/ reverse drum switch and that makes things simple. Check McMaster-Carr or Grainger if you need parts for the starter. Chris (1213)
Tom, chances are the switch is just an extra on off switch. This would prevent the motor from starting after a power failure, or as a safety precaution. It can quite possibly left the way it is or just removed. The barrel switch (railroad) switch is all that is needed to operate the motor, and is standard on most units. (1216)
Tom, I've just done a 3 phase to single phase conversion on my lathe. So I've got fair idea of your situation. By wedging the switchgear relay closed your lathe will operate OK with your forward/off/reverse switch. But you're right! Your STOP button won't stop anything anymore. The START button closes the relay to start your lathe and the relay hold up through a set of it's own contacts and the STOP button. Push the STOP button releases the relay, lathe stops, circuit's now ready for the START button again. Simple hey!! You probably have blown the relay's coil. But I wouldn't trust just measuring the voltages either side of the coil. Disconnect the wires on the coil (with the power off) and measure the coils resistance. My coil is about 700 ohms. But that's for 415V. Yours should be somewhat less than that. Certainly, if you read open circuit, the coils definitely gone. If you can measure some resistance then check all the contacts with an ohmmeter. I wouldn't go poking around live AC circuits unless I really needed to - AC is DEADLY!! (Remember that old joke - Q) What's black and crisp and hangs from the ceiling - A) An amateur electrician). If you can't obtain a replacement coil, swap the whole switchgear relay. That's what I did. They're mostly all the same. 1 x coil and 4 x sets of 'normally open' contacts. If you're the least bit unsure of what you're doing ask an electrician - they charge less than mortician!! Oh BTW! I did get a sparky to check mine before I switched it on! Bill (1217)
Here is were I am. Coil is open, i.e. infinite resistance. It should have some resistance, and not be open. Talked to the the place who sold me the lathe, Noel Dempsey, Dempsey Co, Richmond, VA, he has some 13's he is parting out and thinks he probably has the part, also contacted my friend at Plaza Machinery, Joe Bergamo, he too thinks he might have the switch. What Dempsey's said was the 3 phase converter puts out about 220 volts and the coil is rated for 208 volts and if its a bit weak it can and does go. Apparently this is not too uncommon. Allen-Bradley still stocks the coil for about $64, Ugh!, but least you can get it. I will try to get the whole automatic starter unit. Will post after I install new coil to let you know if this fixed it. big tom (1229)
Here is the outcome on the Automatic Starter failure on my 13" SB. Obtained a replacement from a used parted out SB, ck it and it was not open, had some resistance, Installed it and starter circuit worked just fine. Cheked the voltage across the coil and it was about 240v, seems high, but this was line current without the third leg being generated, i.e. phase converter off. Coil is rated at 208v, so herein could be the reason it blew out? Guess we will see how long it lasts. Have determined that it is merely a switch and does not defeat the two circuit breakers in the switch. Anyone know anything about the voltage and whether there is a fix here let me know. Again thanks to Bill and several others for the assistance. big tom (1237)
Tom, Glad to hear you've fixed your problem. As to the fact you're reading 240V across the coil - I wouldn't worry too much about that. The coil would have been designed to handle small fluctuations in line voltage. I did a quick calc on your readings. I had to think back 30 years to my early training. My AC theory and DC theory may be a little rusty! You haven't stated the resistance of your coil, but if we take my coil at 700 ohms at 415 volts using the formula I = E/R my coil draws about 600 mA ( a bit over half an amp). If we assume yours should draw about the same current, your resistance will be about 300 ohms (at 208V). From that, if we take your actual line voltage 240V the current drawn is about 800 mA (I = 240/300). That sought of difference at those voltages shouldn't burn out your coil. These calcs are for DC. With AC you have to consider other factors like impedance, inductance, etc, but the figures are fairly close. In my experience, in the old electromechanical telephone switches, coils will burn out if you look at them the wrong way (just to spoil your day). In truth they wear out just like any other part. Stop worrying about your coil and start making chips! Bill (1243)
Bill, ck with ohm meter, about 1 ohm????, even disconnected one lead to ensure I was not getting a read through a wire or something, must be something wrong, certainly would not have 240 amps running thru this, good grief. Must be something is wrong with meter. However lathe works just fine and will continue to use it, if the coil goes, so it goes. Anyway I now fundamentally understand the switching function of this device to include the two overheating kick outs. Will let all know if it blows again, and ck with Dempsey about another back up. Bill are you in Australia? big tom (1247)
Tom, Yes I come from the land down under! I live in the south western suburbs of Sydney and work a couple of miles from the Olympic site. I'm on this list because I own a Hercus model 'C' 9" lathe, which is a clone of the South Bend model 'C' (see pics in the 'Files' folder). They say that imitation is the sincerest form of flattery! I would check your ohmmeter! 1 ohm is not far off a short circuit. Unless you have other components in the circuit like a large resistor, 1 ohm across 240v would at least dim the lights of every house for a couple of blocks around you, apart from making your lathe glow red (57.6 KW - P=ExI) I've done some further checking since my last reply. I checked the resistance of the 240v coil of the switchgear I installed to convert my lathe to 240v from 415v. It's about 650 ohms. So the current drawn by that is only about 370 mA. The old coil rated at 415v was 700 ohms, so in hindsight I probably could of gotten away with rewiring the old switchgear. The old switchgear incorporated the thermal overload breakers. Luckily the new 240v motor had it's own overload breaker and I didn't have to worry about that when I swapped switchgears. Bill (1255)
Bill, Well finally got a hold of a digit volt-ohm meter, my coil on the starter switch, 13" SB is 685 Ohms, so at 240v its drawing about 350 mA based on your analysis. Working fine so far. I will see if plaza machinery has located another replacement just to have a back up. again thanks for the assistance. I might not have mentioned that when I went back to Dempsey Machinery in Richmond, VA, to pay for the coil, I wound up buying the whole rest of the partially parted out 13" SB, got a nice drum switch, bed, headstock with spindle, motor, base, apron with most parts for $80 which included the coil. Will put some of it on ebay, but most is too heavy to ship. Also will be purchasing a new meter. big tom (1298)
Tom, I'm glad to hear it was your ohmmeter that was wrong and you have what looks like a normal coil. Good deal an spare lathe. Good idea on selling your spare bits on Ebay. Say why don't you sell each part 2 or 3 times. Take their money and don't ship the parts to anybody. You could change your name to Al and... Oh hang on that's already been done! Seriously, it's hard to imagine someone like Al Babbin and companies like Dempsey Machinery existing in same world. But what the heck, we have our share of rogues and con men here in Aus. too. Bill (1301)
1953 South Bend Wiring
I have a 1953 South Bend Lathe with a GE Model No. 5KC45AB1421,1/4Horse Power; Single Phase;TypeKC;1725 RPM;115 Volt; 4 Amp.;60 Cycle Motor and a Furnas Switch Type RSB44. Motor has 5 wires Numbered 1,2,3,4,5 . Anyone have knowledge how to wire power supply to Switch then Switch to Motor. I have tried South Bend to no avail ,as well as a couple of local rewinding shops and Home Shop Machinist message board. Furnas Switch has six terminals,3 on right side,3 on left side. Switch is neutral in center position. I can't read Schematics, but line drawings showing location of each numbered wire from motor to switch and from switch to power supply would be most helpful. Mike (6400)
Mike I don't have anything which lists the specific motor and switch you mention. I do have form 645A from SB (undated, but likely from the mid 1950's, since that is the vintage of my lathe). Only one picture shows a 5 wire motor labeled 1-5 with a Furnas drum switch. The chart refers to the motor as a "GE capacitor type KC, instant reversing, single phase", which partially matches yours as far as it goes (you didn't mention instant reversing) . The controller shown is a "No 789 Furnas drum switch RSB 5". It has two rows of 3 contacts, as you describe (but many of them do). If you want I can describe the configuration (I don't have a scanner) and you can try it. Frank (6401)
Please describe wiring. My motor is instant reversing also. Thanks. I noticed from some literature, that right side of Furnas switch is usually designated from top to bottom A,B C Left side D,E,F. If you can describe each wire number that goes to each letter, I think I'll be able to follow it. Also, please tell me what letters the power leads go to. Mike (6402)
Mike If the drum switch contacts are: D A E B F C viewed with the handle at the top, then connect as follows. motor connection 1 to F motor connection 2 to E motor connection 3 to D motor connection 4 to B and C (jumpered together) motor connection 5 to one side of the AC line switch connection A to the other side of the AC line If you want the motor to go the other direction for a given switch position, reverse motor connections 2 and 4. When you try it I wouldn't leave it connected very long if the motor doesn't start rotating right away. If this isn't the right connection I expect it would be easy to fry the motor if left connected for any duration. Frank (6403)
You mentioned schematics, if you have schematics, post them in the photo's section. It should be very easy to wire if you do have them. That is if they are the motor schematics. The drum switch might also have them, but that is not too important as you can figure that out with a continuity tester. A 5 wire is typically on for neutral (or power) that goes direct and not through the switch. then there would be 2 wires that go from the power (or neutral) to the motor direct. then 2 that get reversed. swapping those two would determine direction. The complication comes if the motor is dual voltage. Dave (6406)
The schematic I mentioned was from a internet source for general wiring of Drum type switches. As related, all I know is 5 wires coming out of motor numbered 1,2,3,4,5 and Drum Switch. I failed to mention that terminals E Fon Drum Switch are jumped. Mike (6410)
Tried your wiring plan. Got motor to "Hum" on forward, shorted out on reverse. Drum Switch was already jumped at terminals E F. I changed to C D. Mike (6411)
Correction on my last e-mail. I jumped B C as you advised. Mike (6412)
[snip] doesn't start rotating right away. If this isn't the right connection I expect it would be easy to fry the motor if left connected for any duration. To prevent the magic smoke from escaping from any of the components, temporarily wire a 100 watt light bulb in series. If you miswire something to create a dead short, the worst that happens is the bulb lights to full brightness. If you wire it correctly, the motor should start turning if there's no load. A 100 watt bulb will limit the current to just under 1 amp maximum. Ken (6414)
Mike See if you can find a schematic of the specific motor you have. If you can find that I expect we can figure out how to run it with the switch you have. I would try calling GE and see if they can supply a schematic. I wonder if the rewinders you spoke to have a reference showing schematics, even if they don't necessarily know how to hook it up with your controller. Don't worry about not being able to interpret the schematic yourself. Just get a copy, and either scan it or mail it. If you can't come up with a schematic, do you have an ohm-meter, or know somebody from whom you can borrow one? If you can supply resistances between various motor connections I expect we can take a better guess at reasonable connections. You will need to measure all combinations of the motor connections, and check "zero" ohms on the meter (by connecting the leads) to make sure the relatively low resistances you are measuring are reasonably accurate. Actually, if you find an ohm-meter, determine which connections on the switch are connected to which others when the switch is in each of the 3 positions (I expect that none of the connections are connected to any other in the center position). I have one schematic for a Furnas drum switch, and it seems to imply they are all the same, but it is worth verifying. Frank (6415)
Ken I agree the 100W bulb (or other resistance) in series is a good general technique. I don't like series resistance as much for motor testing, since it can prevent the motor from starting. My experience is that it is pretty hard to damage a motor with the voltage it was designed to run on (i.e. 110V on a known, 110V motor) if the voltage is only applied for a few seconds, since the damage mechanisms are thermal, and the thermal masses are generally large (i.e. it takes longer for the magic smoke to escape). Frank (6416)
I got it wired. For the record it goes like this. D-No.2 A-No.1 E B-No.4 F-No.3 C-Hot Line No.5 wire- Neutral Line. Terminals E F are jumped. Motor wired for Clockwise rotation. Instant start up. Runs very smooth in both directions. Mike (6418)
Forward/reverse switch wiring diagram
Does anyone know how to wire the forward/reverse switch for a SB9C?I have it wired to operate in forward but would also like to have reverse capabilities. Bill (7695)
Are you using 3 phase or single phase power? John (7697)
John, I am using single phase. The motor is 1/2 hp.110/220v Capacitor start. The motor has reverse capabilities. Bill (7700)
Bill I was going to go home and look at my motor and drum switch but decided to go a Google search first. Take a look at the following site: http://www.metalwebnews.com/howto/elec-mtr/elec-mtr.html  I just skimmed it but it looks like everything you need to know is there. I haven't checked the diagrams (they are in ASCII) I'll try to draw up a better diagram tonight. I don't think there are enough poles in the drum switch to switch both leads and get reverse as well, therefore you have to make sure that the hot wire is the switched wire. This will work at 110V but I'm pretty sure it can't be done at 220V. At least not in a safe manner. One thing you should note is that you won't get true reversing with single phase. The motor will run in either direction but you have to wait for it to completely stop before reversing. John (7707)
John, thanks for the information and link. I added the url to my favorites and also saved the page for further viewing. I must say the ASCII drawings are hard to understand and read. Bill (7708)
John. BTW I will be using the motor on 110v.I don't have 220 service in my shop yet. I am trying to get everything set back up. I just moved to a new location. Bill (7709)
Bill, Have you looked on the inside of the drum switch cover? Both of my lathes had wiring diagrams glued inside the switch cover that showed how to wire up two different types of motors. Check there and if you don't find what you need, I'll copy mine and post it for you. Glen (7713)
Glen. Took off the cover and yep there it was. Boy do I feel stupid. It was right under my nose all this time. I never even thought to look there before. Bill (7714)
Reverse switch
Where can I find a forward/reverse switch for my 9c? I thought I had seen pictures of them mounted on 9a's and 9b's. Rich (8774)
Rich You can find reversing switches at WW Grainger. They are in most cities. You have to be a business to buy there but any business card will do it. They have gears, motors and all sorts of cool stuff. They give you a huge catalogue for free. max (8780)
That switch is a common "drum switch" it is available at any electric supply house. It can be used to reverse both single phase and three phase motors. You will need to know the horsepower of the motor and the voltage at which you are going to operate it to select the switch. RC (8783)
What's this switch for?
I picked up a 9" model A tonight. Seems to work ok, will need a lot of help rebuilding though. She's a CL344ZD, sn 52561NKR9. The motor has been replaced with a Leeson 110V, and there is a switch in the middle of the stand that says forward and reverse, but isn't hooked up. Is this a power/direction switch? Also, where can I get manuals and such. Almost every handle on it has a ton of backlash, including the feed. The bed is in good shape, and it does run. But there is work to be done. Steve (10688)
Sounds like you got the product of a Saturday afternoon electrical job. often if a switch goes, the cost of a replacement is so high, people will use what is laying around. or bypass it for a variable speed drive. it seems to me that I see a lot of drum switches mounted on the headstocks. (10694)
Hard to tell what the switch is for and if you can use it, without a little more info. you will need to know if the motor is reversible ( look at nameplate or wiring diagram). most if not all SB came standard with a reversible motor but this was with the standard f/o/r switch ( forward/off/reverse) switch to control the motor. the wiring diagrams are in the files here on the board. if you have a standard SB switch and reversible motor you can probably rewire for this use. many motors are non-reversible and if you need that feature you are better off to get a motor made for it - they aren't usually much more expensive than the non-reversible -on the used market. if the motor is not reversible you can replace or use as-is, just skip the SB switch or remove it until you want to go both ways. i use reverse very sparingly and seldom under load ( this tries to spin the chuck off the threads.) it is useful for things like backing up for threading and some other stuff though. (10696)
The reversing switches have some uses, but on a lathe with a threaded spindle there is always the possibility of unscrewing the chuck or faceplate if you run it in reverse. I avoided the temptation By removing the drum switch, and installing a regular toggle switch, in an ordinary electrical box, near the tailstock end of the lathe. (You may not want yours that far down, my machine has a 3' bed) Locating the switch away from the headstock means you don't have to reach past the rotating parts to stop the thing. The person who installed the single phase motor on yours may have taken one look at that switch and just shook their head. Its a triple pole double throw switch capable of reversing either a single phase or a three phase motor, within its horsepower rating. Without the diagram its a head scratcher to hook up on a single phase motor. You have to go into the terminal box of the motor and bring out the start circuit leads. Those leads are connected to the drum switch so their polarity will be reversed. The third pole of the switch is used to make and break the run circuit. Not a pleasant Saturday afternoon for those unfamiliar with this sort of thing. Rob (10697)
Clarke, Tell me about it! When I got my lathe the motor was a non runner. I got a good reversing motor to replace it, but spent not only an unpleasant Saturday, but into Sunday too, and never figured the thing. In the end, I got a decent new NVR switch and went for the one way operation. The big fat red stop button is an easy hit now. The little clamp bracket with the set screw that held the original SB switch onto the front of the ways, I now used as an adjustable stop marker. Len (10699)
Steve There should be a schematic inside the cover of the switch and one on the motor detailing which leads get power and which leads are changed to reverse the motor. Send me these two schematics and I will try and figure it out for you. max Now own a project lathe, what's this switch for? (10700)
I don't see any schematics on the switch anywhere, so I took some pics of it and put up a temp webpage for you to check out. The motor is a 110V leeson single phase that claims it is capable of CW or CCW rotation, whether it will shift "on the fly" is another question all together. The drum switch (?) has 6 leads coming out from it (3 phase days?) Anyway you can check out the pics at http://www.turningwood.com/southbendswitch.htm  Steve (10712)
Its the same as the switch on my SB9 from the 50's take a look at this page there's a butch of pics of the shop there about half way done you'll see some pics of the southbend and where it mounts on mine I've seen a few others with this same switch. Some where I've got schematics on how to wire it, My motor will not reverse anymore and its not weird to spec now so I can't just look but I'll try and find what I have in the CD pill. The Wood Dragon (10715)
No, all that is there is correct. All the leesons I have dealt with have either 6 or 8 wires, all 110/220 single phase. the individual wires are the motor windings. nothing funny with this. The Tx numbers are their manufacturing standard. re-read the motor nameplate. See where it says interchange wires T3 T5 to change rotation. applies to both voltages. No look at your drum switch. you should play with it with a test light or a VOM/ continuity tester. PLEASE use a low voltage test light. If you must use 110V, BE CAREFUL! what you are NOT showing is the drum itself. It will probably look like to copper "F"'s , one inverted and backwards nested into the other. That is really the business end you need to look at. you can see the bottom of the fingers in the open shot. By the way, the one on the 'top' looks REALLY worn. You should consider replacing the whole thing. They are only $35 or so from Grainger, McMaster Carr, etc...cheaper than a new motor or your health. assuming 110V, you really only have 4 wires to deal with "T1/T8", "T2/T4", T3 T5 these are marked on the wires themselves. You need to figure out which terminals are common and which are criss crossed. For sake of discussion, we will number the terminals like this- 1 2 x 3 4 x 5 6 x notice the jumpers across the terminals from 1x, 3x, 5x. I think you can interchange those terminals. in fwd (CW) position you will find that terminals 1 3 5 are continuous and 2 4 6 in reverse (CCW) 1 4 5 and 2 3 6 are continuous. so you will wire it 1 hot 2 neutral (power cord) 3 T3 4 T5 (to motor) 5 T1/T8 6 T2/T4 (to motor) i may have cw/ccw mixed up. I have to look at the lathe to figure it out. But I think you get the idea now. If you can, post a pic of the drum itself to be sure. dennis (10717)
Can you get a picture of the wiper (rotating part). I need to know if there is some internal connection or if they just connect terminals. Jim B. (10720)
Near the end of the Army's South Bend lathe manual is a wiring diagram for the standard South Bend single phase drum switch. This site offers a free download of the manual. http://metalworking.com/DropBox/_2001_retired_files/sbarmylathe.pdf  Rich (10721)
I have posted internal "guts" pics of the switch. Steve (10724)
I have posted the pics and run continuity checks across the pins. For the sake of argument, I have numbered them sequentially (9 contacts total) 123 456 789 There are physical wires coming out of 1,2,4,5,7,8 The jumper wires go from 1-3 4-9 7-6 Numbers show where I get tome With the switch in off 1-3 4-9 7-6 Reverse 1-2-3 4-8-9 7-5-6 Forward 1-2-3 4-5-9 7-8-6 (10725)
SB 9 motor Switch Diagram
Clint, Here is one more piece of info that might be useful. Please be kind, I've been up late drawing this out. Webb (10894)
I've been up late drawing this out. The orientation of that drawing could be misleading to the unknowing. Drum switches are usually oriented ABC in the vertical mode. The drawing shows it in the horizontal mode. No problem for someone familiar with the scheme. Somewhat confusing to a non electrical person trying to connect those wires. RC (10897)
Can you actually buy the replacement switches from SB? I would like to "restore" my lathe and want to use the same switch.(10900)
Does SB sell replacement switches for the lathes? I would like the same drum switch as what came with it, for nostalgic purposes.  Steve (10901)
Webb and all, I added a bit of detail to the switch picture showing the contact action and motor coil/switch names. RichD (10902)
I have a revised and I hope, improved diagram based on the suggestions posted here. Webb (10905)
At the risk of being boring, I have included a 230V single phase version for those who wish to wire their lathe for 230 Volts. Webb (10912)
Asbestos & Old Switches
I was cleaning up the old electrical to my recently acquired SB 9. Upon removing the cover to the 1946 Cutler-Hammer rotary drum switch, I noticed a 2" wide, 1/16" thick liner of asbestos tape probably for heat/spark protection in a friable condition no less. I carefully placed a layer of electrical tape over the broken areas of asbestos tape. Just wanted to let you all know, be careful with old electrical items, the can contain asbestos. Also take caution when blowing with compressed air, items which may contain asbestos. Eric (11486)
Wiring motor to reversing drum switch
I'm trying to wire up my 9" South Bend. I have a G.E. capacitor start single phase motor. It is a four lead type I believe. The drum controller is from Arrow, Hart and Hegeman Electric Co. size 0. I'm not an electrician so if anybody could give me a clear and simple wiring schematic to attach these to together for forward and reverse I'd really appreciate it. I have the wiring schematic for the switch but it really doesn't explain which wires are which. Unfortunately I don't have the wiring schematic for the motor. Bill (11769)
Bill, I have the exact problem as well. Hope someone will post a wiring diagram. I have a single phase 1/2 HP GE motor and a Cutler Hammer reversing drum switch. Eric (11789)
Bill Wiring up your motor would be a cinch if you have an ohm or continuity meter. You have the wiring schematic for the drum switch which ought to be easy to follow, probe around with the meter to verify contacts behave as you understand the schematic. Check your work before plugging it in and switching on. Now the 4 lead motor and don't forget the 5th lead which is the green ground wire.. Two of the leads are the motor windings and will check out to have about 2 and 1/2 Ohms and the other pair will be wired direct (except for the mechanical switch inside the end of the motor), one wire to each terminal of the motor start capacitor. Between the two wires will be 2 or 3 megaohms resistance. So to run the motor connect a capacitor lead to one motor winding lead and the other capacitor lead to the other motor winding lead. Motor will then run in one direction. To run the motor in the other direction you will be wiring in the drum switch to swap the motor capacitor lead positions.. . You have no problem you cant readily figure out on your own. Worst screw-up I did to have a similar problem was one time I removed my 3 phase motor from the top of my vertical mill and sat it on the mill table. I did that to change the pulley belt and then I bumped the motor off the table and because the wires were only so long it ripped all 7 wires out of the motor terminal block. The drum switch on that machine gives me two speeds in each direction. It took me an hour of head scratching and probing with a multimeter to get it sorted out. I am not an electrician either. Steven (11793)
I have a sheet that shows 6 different wiring diagrams. They cover the following: Furnas drum switch with GE motor single phase, Furnas drum switch with Westinghouse motor single phase, Cutler Hammer drum switch with Westinghouse motor single phase, Cutler Hammer drum switch with 3 phase motor, Cutler Hammer drum switch with 2 phase motor, Cutler Hammer drum switch with GE motor single phase. I do not have a way to scan them so I can either fax or mail them. Please advise if interested. Rose Marvin (11795)
Rose, If no one else offers, I can scan in your documents and place them in the group (assuming its okay with LeBlond). Paul R. (11796)
Thanks Rose and Paul for the wiring diagrams. Now to see if I can figure them out. The top left diagram appears to be the closest to what I have. I just wonder if the number sequence is just for orientation. On my motor the number sequence seems to be reversed. I also have no numbers 1 or 6 . Where these numbers are are where I believe the AC power is connected. Bill(11952)
Cutler hammer drum switch
I have a 10" heavy. It came with a 3ph motor I am changing it to a 1ph motor. does anybody have a wire diagram for using the existing drum switch to rewire for the new motor. Dan (14349)
If you go to the South Bend Lathe Pic on the Yahoo group there is a schematic that may be of help. Dave (14350)
Dan, A month or two ago I uploaded a copy of the wiring diagram I found inside my Furnas drum switch to the Files section of this board. It shows about 6 or 8 different hookups for various types of motors including a 3 phase "Y". It is in several different file formats so you should be able to view at least one of them. I would assume that other brands of drum switches are much the same. One thing you must be sure of is that it is rated for the voltage and current involved. Voltage is probably OK but check current carefully or it is in danger of burning up. Current will be higher with a single phase motor of the same hp. As I said, this is a copy of the original. I tried to reproduce it exactly as I wanted to mount it in the original location after cleaning and repainting the switch cover. I even used similar fonts. My original is now a pile of pulp that's been flushed out of the bottom of the ultrasonic cleaner. Paul A. (14392)
Dan, I changed my motor and have the same switch. The wiring is motor dependant. The top contacts are the on/off and the lower two act as a reversing switch for a single phase motor. Send me the motor wiring and I can create a schematic for you. (14395)
9C workshop forward/reverse switch
While cutting threads (no chasing dial) on my 9C workshop(1938) pedestal, I lost the reverse side of my canister style switch that is mounted on my rocking pedestal. Can these switches be repaired? Rick (15027)
My experience is that with these drum switches, the fingers wear out where the contacts touch. Not really worth fixing considering that a Dayton drum switch from Grainger or McMaster Carr is $35. dennis (15028)
You may be able to get the switch going for long enough to finish the thread by using an ignition file on the contacts. I would then proceed to replace it. (Don't forget to unplug the machine). Reversing a lathe with a threaded spindle isn't a real good practice. You can use a thread dial or a carriage stop to catch threads, and replace the drum switch with a regular switch. RC (15034)
Electrical switch heavy 10
Would anyone out there have a picture they could email us of a heavy 10 with a twin lever gear box with either a push button or toggle lever reversing switch mounted on the front of the lathe just below the pan? We are currently restoring a 77 model, 4 1/2 foot bed and all we have in the electrical is a square hole where it went. A picture of some of the options of how South Bend put them out would be very helpful. Our other lathe just like it the switch riser comes off of the back of the bed at the head and this bed has no place for it. Grumpy (16886)
Check in the FAQ in the files section. Scroll down to drum switches. SouthBendLatheFAQ.html If the answer isn't there, have a look inside the drum switch on your other lathe. Both of mine had wiring diagrams inside. Glen (16887)
Did you try the files section of the group? There are wiring diagrams under techinfo folder. dennis (16888)
I have a Heavy 10 with a secondary switch in the cabinet as well as the switch on top. The lower switch is for the RARE South Bend option of an independent motor for the gearbox. Look at my homepage for pictures http://home.pacbell.net/daveanne/index.html (16908)
Cutler-hammer drum switch wiring
I know this subject has been covered numerous times but I still can't find just what I need. I am in the process of changing the old 3 phase motor on my Heavy 10 for a modern Dayton 220 volt single phase unit. I have downloaded all I can find on the matter, including the original south bend instructions, but all applications show 4+ wires coming from the motor to the switch. Per the diagram shown on the side of the new motor, I am only left with 3 leads (2 hot, plus one neutral to hook up to the switch. Also, my power supply from the breaker box to the switch will be 2 hot plus one neutral. I suspect part of the issue may be with the wiring to the start up windings but am not sure. Mark (17502)
Mark, a 220 1 phase motor can have as many as 3 coils and 7 wires available. What type motor is it? What is the starting scheme? Is it a dual voltage (120/220) motor? Slit phase, split phase cap start, etc. This info is needed to help find the correct connection. RichD (17503)
I will collect the specifics and re-post. Mark (17504)
I have posted a picture of the motor plate in southbendlathepix. It is under "photos" and is #28. The motor I am going to install is a Dayton, 6K305C, 1.5HP, 1PH, 115/230 volt, capacitor start, 1725rpm motor. It has 7 connections available. These are listed P1, P2, T2, T3, T4, T5, and T8. P1 is grounded to the motor frame, and the picture listed above shows the recommended connections on the motor plate. Mark (17505)
Mark, Are you sure P1 is connected to the motor frame? Have you checked with an ohm meter? Looks to me like it's for one side of the 220VAC line. T4,5 is the other 220VAC connection. RichD (17506)
I checked P1 and it is NOT grounded to the frame. Any help on where I go from here? (17508)
Mark- did you get paperwork on the motor? It gives you instructions on what the wiring is for your voltage? Just a thought, but you could call Grainger to talk to their tech support folks. That motor is still in production. You need to figure out the wiring of the motor and then that of the switch to mate the two. dennis (17509)
Mark, I can't make out in the picture what the label says next to "P1" It sort of looks like "Ungrd'd and Line". So, according to the label Pi is one side of the 220 line and the T4/T5 tie points are the other side of the 220 line. Tie the others as shown and tape (insulate) as shown. This is all under "Hi Voltage". The label is marked "115/220", a dual voltage motor. Try that to get it running one way. If you want the motor reversible....next discussion? RichD (17510)
It does say "Ungrd'd line". I think I can get it running one way but the real challenge is getting it running through the drum switch so that it is reversible. The P1, P2, T1, T2 stuff must be some sort of industry standard but my web searches so far haven't turned up anything. The joker in the deck seems to be the starting windings and the capacitor and how those are connected to the rotary switch. I got the motor with the lathe and so don't have any documentation for it other than what is printed on the face plate. Mark (17511)
I am familiar with these. The P1 and P2 are hooked to the overload protection device inside the motor. P1 takes the input lead and P2 comes from the overload device to provide a "protected" lead for low voltage hook-up. the NEMA standard T1 lead is pre-wired to the overload device. Just consider the P1 as the "protected" T1 lead. This motor can be hooked-up to the Cutler-Hammer drum switch either as a 115V or 230V operation. IS there a particular reason you want to do it in 230V? Anyway, you can contact me off-line grotto-man "at" erols "dot" com. Webb (17512)
Mark, Take the T5 and T8 separately to the switch. More later. The switch should have a minimum of 3 sections. Find the section that has only 2 terminals with the rotating part (drum) shorting between the 2 terminals when rotated F or R only. This is where 1 AC line connects and then to the P1 terminal. This turns the power on/off. The remaining sections form a reversing function and can be built several diff ways depending on the particular switch model. The T5 and T8 wires connect thru the switch and then to the T2/3 and T4 motor wires. Throwing to F or R reverses the connections. Study the mechanical build and action of the switch to figure out how to connect it up. It's not that difficult. RichD (17513)
I got mine wire up using info from this site: http://shop.emotorstore.com/estore/TD_Schematic_Diagrams.asp?  Ed (17514)
My guess would be the extra wires are due to the reversing drum switch, not fancy number of coils. At 01:05 PM 2/29/2004 -0500, you wrote: Mark, a 220 1 phase motor can have as many as 3 coils and 7 wires available. What type motor is it? What is the starting scheme? Is it a dual voltage (120/220) motor? Slit phase, split phase cap start, etc. This info is needed to help find the correct connection. RichD (17517)
Drum Switch Wiring
Does anyone have a wiring diagram for a drum switch connected to a motor wired for 220 volts single phase they can email me. Tom (19625)
But be careful using a wiring diagram that isn't original to your switch. I just rewired an old switch. The diagram wasn't legible so I started to use the diagram from my newer switch on the other lathe. Almost as an afterthought I got out my ohmmeter and tested the old switch to verify their internal connections were the same. Surprise!. But much better than being surprised at 110 volts. (19669)
Furnas Reversing switch HP1 style R1A 220VAC wiring
I finally converted my Peerless repulsion/induction motor to 230VAC after many years of running my 9" SB Model A at 115VAC. And I'm trying to figure out how to rewire my Furnas Reversing Switch for 230VAC....I realize previous answers have been submitted on this but they all seem slightly different than what I have: Peerless repulsion/induction motor with leads T1, T2, T3, T4 only. 230VAC now comes in on T1 and T4 with T3 and T2 jumpered together. Furnas Switch: Fwd connects F1-R1, F1-F2, R2-R3, and F3-R3. Rev connects F1-R1, R1-R2, F2-F3, and F3-R3. So my question is - where do I hook up T1, T2, T3, T4 without creating smoke? Mort (23559)
Mort: Repulsion start induction run motors are not electrically reversible. The direction of rotation is set by the physical position of the armature brushes. On yours, you can make it 110V or 220V by wiring two windings in series (220) or in parallel (110). Your described connection- with the two "taps" wired together- sounds correct for 220V. These old motors start like a universal motor (look at a Dremmel) using brushes on a segmented commutator to set up a fixed-geometry repulsion between stator and armature. Once up to speed, a speed sensitive switch shorts out the commutator, converting the motor to an induction type. If the centrifugal switch doesn't change, the motor will continue speed up. Since back EMF is not balanced to limit max speed, it may get fast enough to break things. The Furnas switch should be used as a straight switch- make/break for L1 and L2. With 110, you only need to switch one leg but both need to be on 220. Leave T2 and T3 connected. Reversing one leg won't make it run backwards but will make smoke. Somewhere on the motor should be a mechanical connection that rotates the brush position. This is what reverses these old motors. I suppose some may have had an electrical reverse circuit (more than two brushes?) but that would need access to more than the four wires you have. Bill PS- I am not an electrician. This is my understanding of the system- no guarantees. I strongly suggest you find someone with experience and training to give you a hand since I can't actually see/test what you have.  (23585)
Bill, after further investigation, your analysis is correct. I need a T5 and T8 lead. The brushes are marked with small arrows and rotate about an 1/8" to make the motor reverse. Bottom line, I have an expensive on-off switch and have to reverse the lathe with the reverse gear set. This, of course, makes cutting threads somewhat difficult without investing in a new motor. Mort (23595)

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