Rick "needs the 2" belt to carry 2 HP" Denney
Oh I remember those days with the ancient flat bed lathe I used to have, belt splicing and all that stuff. 
tick tick tick it went, some days theaurapedic, other days darn annoying !
All open gears on that old thing, I had a total of just 6 when using the back gears.....70's
Spindle bearings, well they were big tapered bronze bushes of which you had a ring nut on one end to adjust out most excessive play however you had to retain some small play for the lube oil.
500 RPM was as fast as I was game to run it. 
By todays standards it was a horrible old piece of poo but it got me back into turning decades after doing it at High school.
Poor old terribly worn out thing it was but it came for $0 from a scrap dealer mate plus a 30 minute drive to collect it.
The South Bend S-series from the 40's to the 70's was sort-of the culmination of this design, which has its roots in line-shaft shops with steam-powered line shafts of the late 1800's. It was maybe about the start of that period when companies like American, Monarch, and Axelson (in the USA, and among others) started making gear-head lathes with real geared transmissions to drive the spindle and not just the power feed screw. But South Bend adjusts the journal bearings using a bronze sleeve that surrounds the hardened steel spindle. The sleeve has a slot with an internal dovetail, and the adjuster is a flat bronze bar with angled sides to engage the dovetail. That plate is held in place using two screws through the bearing cap, and the tension on those screws can spread the sleeve, adjusting its circumference around the journal. But removing the cap requires completely removing those adjuster screws first--prying off the cap usually strips the dovetail and that is a Bad Thing. The caps are separately spaced using a shim stack that starts with 30 sheets of 0.001" brass. You peel them away until the sleeve doesn't move under the cap, and the adjuster is set to allow 0.0007-0.0012" of vertical play using a bar inserted into the spindle. When the spindle is running, oil-film pressure locks that play down to a couple of tenths at most.
But all the gearing (to transfer power to the quick-change gear box, in that gear box, and in the apron) are square-cut spur gears so they make a racket. The Monarch and Axelson lathes used angle-cut transmission gears in the gearbox, like a car transmission, and they are quiet and powerful.
I don't mind the drive belt, though. It's much more forgiving of a Big Mistake. If I crash the lathe or take too big a bite with my tooling, it just pops the belt off the pulley instead of destroying itself. Not that I've ever done that (uh, yeah). I did replace the original leather belt with something modern, however.
Most lathes use V-belts to transfer power from the motor to the spindle transmission--in my case the jackshaft that is on the other end of that 2" belt from the spindle. My V-belt pulleys were sized for a 1425 RPM motor--originally 525 V, 25 Hz three-phase. That's what Bethlehem Steel used, and they were the first owner of my lathe. They repowered it with a 2-HP single-phase dual-voltage motor when they sold it in the 60's. That motor turns at 1800 RPM. They used different pullies, but the pullies they used didn't restore the factory speeds and my top speed is more like 1075 RPM. It will run at that speed all day without getting more than a bit of warmth on those journal bearings. But I'm usually using 250-600 RPM for most operations. The ticking of the belt splice bothers me not at all--often I can't hear it over the clatter of the power feed gearing.
When I got it (obligatory EE-type content), the dual voltage motor was wired for 240VAC except for the starter circuit. These usually have two field coils that are connected in series for 240VAC and in parallel for 120VAC, and the starter circuit is either connected in parallel (for 120VAC configuration) or between one line and the center tap between the two coils (for 240VAC configuration). On mine, the starter circuit was consistent with the 120VAC, but the coils were still in series. It had a 20-foot 16-gauge power cord with a 15-amp 120VAC plug on it (U.S.-style). Lessee, it's a 2-HP motor that pulls 25 amps starting/18 amps under load when wired for 120VAC using a 16-gauge cord and a 15-amp plug--what could possibly go wrong? It had been used that way for 40 years, but it worked because the coils were in series. No wonder it was always in the lowest speed--60 volts on each coil probably couldn't make more than half a horsepower and the motor wouldn't even get up to speed without bogging down with the belt on the high-speed pulley. I rewired it for 240VAC properly and now I can take quarter-inch cuts (half inch off the diameter) at 600 RPM and 0.005 feed in 3" steel bar stock using carbide insert tooling. The chips come off glowing and turn blue on their way to burning a hole in my jeans. Those old lathes do work.
Fortunately, mine was reground at some point and the carriage ways rebuilt with bronze plates, so it's approximately straight and true, though not perfect.
Rick "has fun with it" Denney
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