The first line of defence always is dress the backside of the belt with a bar soap well the motor is spinning. A soap bar has a very sticky transmission drive.
your machine was not designed for a V-belt or link belt. If it has a flat belt, flat belts worked pretty good for over 200 years. My father replaced his flat leather belt with a new leather belt. He did all the hand stitching. In the end he reported that he could cut 0.070". I'm not sure of his horsepower. But I'll look it up for you. He never did use carbide tool tooling inserts. Just high-speed steel.
Most South Bends did not have hardened way during World War II or earlier. They were just soft gray iron floating on lubricant. They started hardening them using KASENIT and torches to give a hardened surface finish in later years before hand scraping. But most manufacturers did this as well. The south bend was known to wear with use as it did not have proper way Harding. Heavily used machines ended up having high wear points in the most used areas. I hate to say this, but this is where some of the old machines lost tolerances and died.
I'll post pics of the tools later today. So if I convert to a link belt it could damage the machine? Pity about the non-hardened ways. I think my lathe is a 1937 model. I'll see what kind of wear there is later today using my indicator dialmounted on the apron. It seems to cut decently but I do feel differences in how hard I need to turn the wheel when feeding the cutter into the work piece so I'm guessing thats probably a sign of wear on the ways.
Here's the one I installed. https://www.amazon.com/gp/product/B00A9ZNE7C/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Yes, Leather belts have been around for hundreds of years. They do work, but We as a society have moved away from the leather belt. What does that mean. They're more expensive, you have to buy some tools to work with them effectively (more expensive), and we've lost the institutional knowledge of working with them. Because the South Bend do not have Vee pullies you have to install the link belt upside down. The link belt is safe for the Lathe. It is a common change done with these old machines. This statement is based on how often it comes up in some of the South Bend lathe/ equipment groups that I'm a member of. These Old boy have some sweet machines. Some are show pieces other get fed a hot supper on the regular. The Old school purists will cry foul but it shouldn't hurt anything if installed properly.
Well I won't toss the leather belt I have but I would like to get more performance out of the motor and less slippage so I wouldn't mind trying it out if you think it grips better?
I would have expected a lathe of that size to have a two horsepower motor?. What do the people over at the South Bend forum at Practical machinist have to say about it?. Also you're going to have to use sharp positive rake tooling with very small tip radius to reduce side load forces on the cutting tool. Negative rake tools or a circular carbide insert will need too much horsepower to work.
Six months from now and some research will have you right up to speed!. That brazed carbide cutting tool in your post #222 has what looks like a left hand 1/8" radius tip which is going to need a tight, rigid/new lathe of about 5Hp to be used without much chatter: the round radius require more horsepower and force to make a cut compared to a tool with a 1/32" radius. Something like the tool This Old Tony grinds from high speed steel at about the 7:00 minute mark onwards would be very useful as the cutting forces are on the lathe spindle bearings and not on the toolpost/compound slide. The right tools can go an awful long way towards compensation for a worn lathe as a skilled operator can produce good accurate work on a worn lathe with the right techniques that an inexperienced operator on a brand new lathe can't duplicate.
Looks like the front way is out by about 23 thousandths across the entire length of travel. If i measured that correctly Some of the tools I have. I've got a few more of similar sizes and shapes.
Tool geometry has a huge effect on the load. I've cut .2 on 1018 with only a half horse motor with a hss bit ground to 30'.
I'd be wary of using the round carbide tool with the black body on your lathe, it would require a good rigid machine with some horsepower to cut anything stronger than aluminium. All of the other tools should be fine to use, although the brazed carbide tool with the gold body on the left is kind of hard to tell from the photo whether it's a left hand tool (like the copper painted tool) or right hand (lathe feed direction cuts toward the chuck) by seeing which way the top face of the carbide slopes. Here's an old trade training film (complete with "Popcorn" synth intro) that I watched recently, it gives very practical demonstrations of tool geometry versus horsepower versus tool life: you can lower horsepower needed to do a job at the expense of tool life and with diminishing returns.
With that dial indicator setup can you push down on the saddle casting by hand at the chuck end and then the tailstock end and get the indicator needle to move as the saddle rocks?. Also the narrow horizontal land at the top of the V way should be free of wear and a good surface to measure from.
Ok I'll check from the bridge between the sloped sides of the ways. And by rocking the saddle. I don't think there's a lot of play in the saddle, doesn't feel loose when it cuts but ill specifically test with the indicator dial later today. What is the range of acceptable wear for a decent lathe? I'll have to figure out how to check the cross slide wear later. I'd like to take the apron off and clean it out. I bet its totally full of junk. Might help free it up. I'll see if there's anyone local that can scrape and see what they'd want to fix it up. I'm in an old mining town in the country so I might get lucky finding someone with old knowledge. I'd also like to upgrade the motor at some point. Can anyone recommend motor specs of what to look for?
Zap, did you level your machine and check it for twist? If the machine isn't perfectly level front to back isn't that important, but TWIST of the bed is very important! The digital levels are pretty pricey, maybe you can find someone with one you can borrow?
Fastest (cheapest way) to check for twist. take a few cuts the full length of a long bar .01-.02" should be enough. Make sure you center drill and support the end with the tailstock (that means align the tails stock to the chuck first) Measure the diameter of the cut up by the chuck and down by the tailstock. If the measurements are different you have a twist. If the measurement is higher at the tailstock the twist is away from the carriage, if the measurement is less the twist is toward the carriage. Tweak it by shimming the feet or adjusting the leveling feet (depends on what's on your lathe). Or follow Old Tony's advise
The South Bend topic over on Practical Machinist forum is going to be your biggest source of information about correct motor sizing and RPM's. As far as scraping the lathe saddle, cross slide and compound slide that's going to be a major effort so it may be better to use the lathe as is and gain experience, make any mistakes and get up to speed on using the machine. It would be better to use it as a place holder while you keep an eye out for a bargain on a newer, more modern design like something from Clausing-Colchester, Harrison, Hendy, Graziano, Mori Seiki or any of a multitude of US built machines from the 1960's onwards. They will have induction or flame hardened ways, reversing clutches, foot brakes etc..
Nope I didn't do that. I dropped the lathe from about 6 inches up onto the concrete and it landed perfectly on the legs. That seems to have gotten the twist out of it that I had seen before at the old house. Now all legs rest squarely on the floor flush. So I guess win win? I cut a 7" long rod like that and it was equal sized on both ends so I'm guessing that means no twist? I call my technique "gravity assisted leveling"
