South Bend 13" Restoration - Back Gears

[@weshenderson4158]

This is a phenomenal video that explains simply how the headstock and backgear assembly works. Took me far too long to find this perfect video. Maybe add "explanation" to the title. I know others would appreciate finding this. Awesome job. Just what I needed for building a lathe.

[@georgebell7103]

Wow, thanks for the nice comment. There are a dozen more videos iin the SB restoration, you may like those as well.

[@weshenderson4158]

Quite welcome. I'll definitely be checking them out. Thank you.

[@oldfarthacks]

George is very good at providing very clear explanations. I am surprised that he doesn't have one of them there fancy KZbin plates on his wall.

[@JaredAF]

Well just got done starting to mess with the backgears. This whole project is spiraling out of control now, started with just wanted to take off the apron, clean and inspect, and well you know how it goes. I already got X off, might as well take Y off. Oh well, I've got Y off, might as well take Z off. Might as well paint it while I'm here. Haha! Anyway, it looks like someone at some point intentionally overinserted or overtightened the bushings with the set screws to freeze up the back gears. After this they cut the heads of the screws, and painted over them. This lathe saw use in a school, so maybe it was for safety purposes? Anyway, after drilling them out, the backgear started to move, but now I'm wanting to remove the entire assembly to clean, inspect etc. Looks like I just have to beat out the eccentric shaft. I tried beating on the center hole, but the thing doesn't want to budge. I might temporarily put it back on the ways, clamp it down, and try to beat it out. I don't think this assembly has moved in decades, and the backgear lever took a lot of working back and forth with a big 3 foot cheater bar to get it to start moving by hand. By the way turns out this a 15" South Bend series O from 1920 with a 6 foot bed. Pretty awesome, as it was sold to me as a 13"

[@georgebell7103]

Yes, you never know the history of these machines. What the previous owner did, or why. Thanks for the comment, and good luck

[@floggerSG]

Had one of these things for years... never could figure out what the heck that did. Thank you!

[@georgebell7103]

You are welcome

[@JaredAF]

Fantastic video. I have a SB 13" from the later 1910s or early 1920s and the back gear is stuck. I can't get any movement out of the lever by hand and I was trying to see kind of how it comes apart.

[@georgebell7103]

Sounds like the perfect video for you…. Thanks for the comment, glad it was helpful

[@NorthwoodsNoise]

Thank you Mr. Bell, this was extremely helpful. I've been trying to figure out the back gear on my 1923 series O for the longest time. I was always confused about why the headstock locked up with the back gear engaged (motor off of course). I never knew of the latch locking the bull gear to the cone. Makes perfect sense now that I've seen it explained. Thanks again!

[@georgebell7103]

Well, thanks for the nice comment, glad the video was helpful

[@ScottRods]

Another fantastic tutorial, thank you. You are winning KZbin.

[@georgebell7103]

Thanks for your comment. I see we have similar interest..... metal lathe and old cars.

[@ScottRods]

@@georgebell7103 This is my first lathe, so I'm cramming like I'm going for a test. It will pay for itself pretty quickly, as old car parts are expensive as I'm sure you know heheh.

[@DirtForester]

Thank you!!! I’ve been trying to figure out how to use the Back gear on my old SB9.

[@georgebell7103]

You are welcome. Glad the video was helpful

[@TWISTEDSTRINGS69]

Excellent video..I just bought my first lathe and it`s a South Bend 10K..needless to say I have no idea what I`m doing. I`m teaching myself how to use a lathe and mill and have been wondering what those gears are for and what it means when they say to engage the back gears...Now I know, thanks a lot, AJ

[@georgebell7103]

Same with me when I bought this lathe, this video series will help you understand the machine. Good luck

[@TWISTEDSTRINGS69]

Thanks, I`m gonna need it ! haha

[@michaelferguson1828]

Amazing job you are doing on that lathe

[@georgebell7103]

Thanks

[@cdrive5757]

This is an absolutely superior DIY video. The clarity of the back gear assy is awesome! Even looking inside the threaded hole of a set screw seat was VIVID! I could see the conical female bottom where the mating male conical nose of the set screw would seat! WOW! Question: Is that a 3/8-16TPI hole threaded for a Pipe Plug when running and a Zerts grease fitting when lubing? My Heavy 10 came to me with just the threaded hole in the sleeve. Thanks, Wakodahatchee Chris

[@cdrive5757]

Reading back over my question I think I wasn't clear. I'm referring to the threaded lateral hole in the sleeve @ kzbin.info/www/bejne/qWa6l6uwor2Wl5I.

[@georgebell7103]

@@cdrive5757 thanks for your nice comment. Are you referring to the grease fitting thread? If so, on this machine it is a standard 1/4 28 thread. However, they might be different on other sized SB machines.

[@cdrive5757]

@@georgebell7103 Thanks for your reply. Somehow the previous owner of my SB-H10 lost the cap screw for that grease hole. Oddly, my hole is a buggered 3/8-16 which I don't think was original and is not as common for Zerts grease fittings. I machined a low profile 3/8-16 screw to plug the hole and ordered some 3/8-16 Zerts on ebay. What I'd really like to do is weld up that buggered threaded hole, then drill and tap it for a 1/4-20 Zerts. Do you know if the back gear sleeve is cast iron? Hopefully it's steel. Thanks again!

[@georgebell7103]

@@cdrive5757 I am pretty sure it is steal. You might just weld it up and tap a proper sized hole right next to it in virgin steel. I have had difficulty taping in a welded area, due to hardness differences.

[@cdrive5757]

@@georgebell7103 Yes, and thank you for the suggestion I like that idea better than mine. Tapping isn't my favorite pastime. Tapping into a weld joint doesn't improve the experience. The only thing I enjoy less is removing a broken one! 😮‍💨 One last question , I hope: The rear of my H10 is against a wall. Do you think I'll have trouble removing the back gear assy because of this? THANKS!

[@FatRedBiker]

Big help watching this! Many Thanks!

[@georgebell7103]

Thanks for your comment

[@jwest613]

Hi George I have a South bend 13" and cant figure out why the back gear lever keeps kicking out, any help would be appreciated Thank you in advance for your help

[@georgebell7103]

I don’t know if I can help you. I have never experienced that issue. If it were my machine, I think it would be a good idea to check alignment of all the gears in the back gear train, and make sure the gear mesh together at a properly.

[@jassiezone]

Very useful, thanks for explanation.

[@georgebell7103]

Thanks for your comment

[@aniruddhashinde]

very helpful and informative video thanks I got cleared my doubts here

[@georgebell7103]

Thanks for the comment. Glad the video was helpful

[@joecalhoon4676]

Hi George, I’m restoring a SB13, your videos are super helpful. Thank you! Question, what grease are you using in the cone and bull gear shaft? I know the Roy Dean product is not available and some people use oil. I would prefer grease.

[@georgebell7103]

I am not familiar with the Roy Dean produce. Yes I think some do use oil, the pulley has the word grease stamped near the hole, so I use grease.

[@georgebell7103]

What ever is on sale… I don’t think it matters

[@joecalhoon4676]

Thanks George,

[@salvadormendez9867]

those rear gears look new i need those gears for my lathe.

[@georgebell7103]

Yes, it is a nice machine. Thanks for your comment

[@joemama22]

South Bend Lathe Bulletin H-2 addresses lubricating the back gear and cone pulley... It recommends using oil, not grease.

[@georgebell7103]

Thanks for your comment. Yes, I believe you are correct. Oil not grease

[@deeremeyer1749]

I'm surprised the ratio is 7:1 input to output. That's a pretty extreme gear ratio. With 4 ratios at the belt pulleys and probably a fair degree of slippage from what must be a flat belt drive, I'm surprised any load large enough to require "low gear" doesn't just slip the belt. The thing about electric motors is that they're "constant torque" and you really don't "gain" any power when you change ratios. You still have the same available "horsepower" since HP is dependent on speed and torque and the speed of AC motors and also the torque is determined by voltage and cycles per second and motor resistance. As an old diesel mechanic with mainly DC motor experience working with starters and such, I'd never really given that much thought until a while back when a friend gave me a "new" single-cylinder air compressor to replace the clapped out compressor I had in the garage. It was just the compressor itself so when I swapped it with the old one and swapped pulleys as well, the higher compression and lower leakage and my "questionable" electrical service (I'm literally at the end of the line in a 100+ year old farmhouse with a 40-year-old addition and an old barn/workshop but nothing has been added for decades and I'm sure that's not the case "upstream") had the old 1/2 hp motor working pretty damned hard. A leaking check valve letting tank air back to the cylinder didn't help and I could actually get more pressure in the tank with the old compressor. It just took a lot longer to get there. The belt ended up going to hell after a couple months and I'd done some playing with a few other pulleys I had to change the ratio for "more torque". As somebody who knows a little about electricity and started studying it "practically" in junior high I should have known I was pissing up a rope. No combination of pulleys and belt gives you more power than you've got and I temporarily "fixed" the issue by doing a "shadetree" fix of the check valve to keep it from leaking back. But It still hits about 80 psi and starts pulling down, lol. So I reset the limit switch to 85 or so and backed off the start side but not enough because once in a while it tries to kick in and just grunts. But it gets tires aired up and runs small air tools for the little bit of stuff I do with them. Electric motors aren't internal combustion engines that can and do make more power the more power they make and "gearing down" an electric motor actually costs you "horsepower" the more stages of reduction you go through. Of course the same is true with internal combustion engines in that there's a torque loss at each ratio change but engines aren't steady-state "power providers". That's the primary difference between motors and engines that gets missed in "debates" about which is which or right. Engines are "multi-stage" energy conversion devices. Fuel/air to heat to pressure to torque. Motors are single-stage conversion devices. Electrical current or hydraulic flow to torque. AC systems aren't terribly good at that since they're switching on and off and are only "on" more than they're off if its 60hz. The two "legs" take time to "charge" and "discharge" and the only point at which you're getting "maximum" power is when they "pass" each other when you're dealing with 220V and both "legs" are connected to the load. 3-phase AC electrical power "imitates" DC but also not terribly well and its inefficient since you're using both "legs" of standard single-phase service and one "leg" of another. Phase converters are also highly "inefficient" and when I see guys talk about using a phase converter to operate a 3-phase "industrial" tool being "cheaper" and/or easier than getting 3-phase service and operating the tool at its proper power level for maximum "efficiency", I kind of have to laugh. Especially when most of them are hobbyists and rarely use the tool and for brief periods of time. They'd better off buying a "cheap" surplus 3-phase commercial diesel-powered gen-set or using a pair of portable generators "in parallel" to power the tool. I'm not sure EXACTLY how that would be done but I know it could be. Having precise voltage control is less important as voltage increases and "220" and "110" and "480" are "nominal" voltage levels. That's the absolute MINIMUM you can have UNDER LOAD and not be overloading electric motors and be producing more "heat than light". The only 480 I've worked around was on center-pivot irrigation systems using a common diesel engine to power the well pump and a generator to run the pivot. Those things use 480 at very low amperages because they're pretty much wired in series with one motor per tower and a ton of gear reduction at the motor gearbox and more at the wheel gearboxes. When they're "moving" its only one tower at a time with "safeties" if they get out of alignment that stop the first tower once it gets too far ahead by openings its circuit and then the second tower can move, etc. It's still a lot of juice given the voltage drop across the miles of wiring but high voltage is the result of low current through "high" resistance. Just like high pressure in a hydraulic system is the result of "low" flow and a lot of restriction. The other issue I see with running big machines with phase converters is you still have 60hz electricity coming in. 50hz if you're in Europe and most of the rest of the world. Combine that with belt-drive machines being worked too hard without enough power and toss on an add-on CNC system and however much other stuff guys end up running simultaneously in their "shops" on household current - lights, air compressor, "entertainment" appliances, etc and I seriously doubt the fact that "220" +isn't a separate service. It's just two legs of 120. 480 is 220 + 220 + a little "extra" gained from the overlap in cycles. You don't ever have one leg at "120" and one at "0" or anywhere close. As one is peaking another is dropping but the third is also coming up. Like I said, its a DC "imitation" that makes up for "constant flow" with "constant pressure". Running machines with less power than they're designed for is NEVER a good idea. No matter the power source and its always killing "efficiency". If you can get by with X 3-phase Y HP machine tool running on a phase converter and can afford that "big" machine and a phase converter and the higher utility bills you'll get "forever" along with getting a lot less bang for your buck out of the machine OR you can do it the "cheap" way and put in a "220" motor on your single-phase, you can get by with a much smaller machine. I know little or nothing about machine tools and machining speeds and such but I do know a LITTLE and I have some boring bar experience and valve grinding and such as well as a lot of "fabrication" and work most guys don't CONSIDER "machining" like grinding, drilling, cutting threads, etc. And it sure looks to me like a lot of "machinists" on KZbin have way more lathe than they need, go like a bat out of hell doing "precision" work and make "how-to" videos where I don't see anything done too "precisely" and when it comes to "measuring", it gets even worse. Lever-style dial indicators to measure "runout" and "concentricity" instead of a standard plunger indicator, using indicators in various fixtures to "measure flatness" or measure dimensions, an obsession with no "runout" and perfect "concentrity" that lasts right up until its "close enough" and within a "few tenths" or a "couple thou", etc. Dial indicators INDICATE. They do not MEASURE because they have "slop" in their own mechanisms. MICROMETERS and other "rigid" measuring tools that can be "tightened" to take the slop out are for measuring. Lever-style indicators are especially "error-prone" since they have multiple pivot points which are "levers" themselves. I also see piles of what have to be old "surplus" tools the original owner "discarded" for some reason or another. Whether its lathes or indicators. CHEAP and GOOD never go together when it comes to tools period unless you're making them yourself and those are expensive in time and the resources required to produce them. And I see "restored" lathes all over that look like they've gotten the old "DuPont Overhaul". A "good" cleaning to remove the oil, grease, rust etc from them and a coat or two of new paint. New parts? Nada. Just knock off the rust, maybe "scrape" whatever "precision" surfaces so they look "new" and like something difficult and time-consuming went into the "rebuild" where metal was removed from a worn-out machine by "machining" surfaces and/or "relocated" to "restore" the parts and get them "flat" or "square" or "parallel" or whatever is supposedly so important to locating a tiny cutting point in space and won't be "checked" by a "machinist" that has some "professional" do the "restoration" of his "machine tools" that he "uses" or features in a few KZbin videos but mostly "collects" and then sells to some aspiring "machinist" to "make room in his collection". I've bought enough good quality tools both new and used over 25+ years to know that if something is AS GOOD AS "NEW" it better BE NEW and if you're paying more than "new price" and in most cases tens or hundreds of times "new price" for a decades-old tool of any kind that was mass-produced and mass-sold to some big company machine shop or the "government" at "lowest bidder" prices back in the day who knows how many "owners" ago, that "new price" had better not be more than pennies on the dollar for what a "similar" tool sells for new. "Inflation" DOESN'T MAKE TIRED OLD JUNK WORTH "MORE MONEY" any more than "restoration" does IF that "restoration" is a "DuPont" overhaul deal or my OTHER "favorite" type of "restoration" I see a lot online called "Bend to fit, paint to match". I'm pretty sure most "restored" machine tools for sale online and I rarely see their proud new "machinist" owners "measure" anything on them.

[@georgebell7103]

wow, you spent some time on this

[@ellieprice363]

Long reply with much valuable information. No, you don’t gain any horsepower with gear reduction but you do gain a ton of torque. That’s why a small farm tractor can pull three turning plows all day with a 35 hp engine.

[@PradeepKumarC-vh5vh]

An 100%apt solution for my problem, thank you sir

[@georgebell7103]

Thanks for your comment

[@wilbertpachecovalencia3029]

Muchas gracias por compartir este vídeo lo nesecitaba mucho porque estoy restaurando un pequeño torno que tiene ese mismo mecanismo

[@georgebell7103]

de nada. gracias por tu lindo comentario

[@priyankmistry1178]

Thank you

[@georgebell7103]

You are welcome

[@marknaisbitt5292]

Thanks so much for this video it has

[@marknaisbitt5292]

Solved so many problems I have

[@georgebell7103]

Great, thanks for your comment

[@timirchakraborty6162]

Nice educational video I am very helpfull for this video

[@georgebell7103]

Thanks for the comment

[@deeremeyer1749]

Having a two-piece spindle like that machine clearly does as well as plain bearings on the spindle "halves" certainly can't do any more for those machines than having the load of a belt pulling on the two-piece spindle "between centers" of the spindle "assembly". And is that lathe built to be powered by a line shaft? I've never seen anything built to be powered by an electric motor have flat belt drive before. Mainly because you won't keep the belt from slipping given the "instant-on" and "constant-torque" nature of electric motors. It doesn't look like there's any too much clearance between the belt pulley and frame underneath, either. Gonna have to be a mighty thin belt to "slip" from step to step especially going smaller on the spindle. All flat belts are "spliced" because they're used where you have to take the entire machine apart to get them "wrapped" but that machine looks like its going to need a belt that has a "zipper" rather than a conventional belt splice.

[@georgebell7103]

Thank you for your comment,,, I can assure you that the flat belt works just fine. It transfers power efficiently from the motor to the spindle,

[@timirchakraborty6162]

Thank u sir

[@georgebell7103]

You are very welcome. I am glad they are helpful

[@timirchakraborty6162]

I feel proud sir to chat with u

[@timirchakraborty6162]

Sir can u pls upload about centre lathe back gear machinism

[@georgebell7103]

I have uploaded all there is on the back gear, there is no additional information. I have shown all the parts. Perhaps you can look at other videos in this series to find what you are looking for.

[@timirchakraborty6162]

Thank u for ur kind information

[@angelorodriguez3003]

you are admirable

[@georgebell7103]

Thanks

[@inigo-dx1er]

Nice consept I from india

[@georgebell7103]

Thank you for your comment. India!

[@osirodo6853]

What a beautiful lathe I have an equal god fill it with life health and charity teacher George Bell

[@georgebell7103]

Thanks for your comment..... and blessings