How Do You Pin a Flat Belt ... Properly?

I'm glad to hear that you are feeling better.

Will the pulley sides keep the pin in place? As usual, I don't have a clue.

Maybe Del does.

Try the Home Shop Machinist Form. Many people there use The old Workshop 9s. I had one for awhile, too. Still have a set of 3C collets around somewhere.

Great. Thanks for the link. It's a nice machine, save for the cast iron bearings, lack of way wipes, and manual change gears. Unfortunately, mine has waaay too many hours on it, and the ways are terrible. Not worth regrinding, so I'm trying to make homebrew moglice.

http://bbs.homeshopmachinist.net/threads/53946-secret-moglice-recipe

Cast iron bearings... ? Babbitt?

After we made a belt after putting in an alligator clip. After you run it, the pins will set. The biggest issue, is making sure the alligator clips are squared.

Yes, cast iron. Probably segmented since you can tighten/loosen them by a cap screw on top. Here's the ugly beast,

On top the headstock, nearest you and nearest the threaded nose, you see the single cap screw.

Cast iron works great as long as you oil it every time you use it.

In my engineering college we had all South Bend lathes. All machines worked very well inspite of being handled by raw students. Hope your problem will be solved soon.

They are lovely machines, but this one is pre standard 9", and it's frankly about wore out. I would have preferred a nice Logan (or even a Myford), but those are beyond my means. Still, I do like the sound of a South Bend when it's running - kinda like an ole Merlin engine.

I took a 8" test cut last night and got a total variation of 0.003". I can see part of the problem - the tool holder/compound slide is not rigid enough. I'm not sure yet what the fix is, but I suspect a decent tool holder should buy me another mil.

This thing has now made me appreciate carbide tools. I always preferred HSS for the little benchtop lathes that I've had, but I switched over to a carbide tool, added a little extra depth of cut, speeded up rotation, and slowed advance, and VOILA! that steel started to shine. I only had some thin oil for lubrication, and the stink annoyed my wife, I think. I gotta get some decent coolant and make a drizzler.

Hi TVP45,

Nice to hear your comments on my post. By the way is this lathe for your hobby purpose or you are planning to make some components. If it is for your hobby lathe then it will serve the purpose. I hope by now your belt problem is solved. Have nice time.

The answer depends on who's asking. If my family asks, it's to make valuable stuff. If you ask, it's to play with - sort of a second childhood. I do have some actual things I need to make, such as 2 axles for my cement mixer turned compost mixer, but I've lived without those for years, so I'm reaching a little.

If I wanted to make parts that mattered, I'd probably look at about a 6" Atlas or else hope I get lucky and find a Logan that somebody sells cheap because it's marked Montgomery Ward.

The belt works fine. It started out quiet, but now it's making the "slap, slap, slap" that is music to my ears. Had to get broken in, I suppose.

You're lucky to have been at a school where they had such lathes. Most kids now, except for the lucky ones that misbehave and get stuck in Industrial Arts, never see how people make a living or learn anything useful.

Looks a bit like my ancient Atlas, except I'm missing the tail-stock and mine uses a Vee belt. One of the kids busted the lead screw drive gears that drive away from the head stock.

Kick the kids out of the house and let them make it on their own. That way you will have more than enough money to buy a newer, better and larger lathe. New lathes with all the digital readouts and such are much less expensive than kids. Also quieter!

Good Luck, Old Salt

Is that one of the lathes that used Zamak alloy for the gears? Those are easy to bust. You can still buy them (except in steel, I think) from Boston Gear. They cost a bit, and you can find them on ebay.

I guess it just stays in once you put some stress on it....

Its all in the belt tension. I work in a facility with roughly 27 miles of conveyor belting running from 1 inch to 5 feet in width and up to 400' plus lengths. We do use that type of pin although ours is plastic coated. Once you have tensioned the belt you'll have to run the machine for a while and adjust the tension a bit more. As you do this you will put grooves in the outer material covering the pin, this grooving will ensure that the pin stays where it belongs.

Besides allowing the belt tension to hold the pin in, there is another way to hold it in place. Put the pin in, turn the belt on it's side over a steel plate. Peen the ends with a nail set used for finishing nails. The pins are usually malleable enough that the nail set will do it. This especially works when the personnel using the conveyors don't keep sufficient tension on the belts. It also is good for you if you have new mechanics who haven't worked with conveyors before.

Good Luck, Old Salt

Flat belt pin. Use a brass or aluminum welding rod. they ware a grove

quickly and won't come out.

If you need the belt lace this can be done at most farm equipment dealers that sell hay bailers

It depends on the finish you require. Pinned belts usually leave some type if mark on the turned diameter. For best finish, the belts are skived and the ends glued. Flat belts normally have a crown that keeps them running true. This crown will keep them centered and keep the pins from sliding out.

Yeah, I thought about skivving a belt and gluing it. I've done that with round ones, and it works good. In this case, I would have to make up my mind before gluing it (pulling the spindle is a pain), and I seldom make up my alleged mind any more. I just put together an old table saw I had laying around. After I got everything mounted, bolted together, and aligned, I picked up the v-belt from the workbench and went, ##@^%!)

Hi Folks,

Although I suspect the belt tension does play a part holding the pin in place, the pulleys play the real part. The edges of the pulleys keep pushing them back in. If the pin was to start drifting out, the shoulder of the OTHER pulley would push it back.

On my 1928 Southbend even the outter most pulleys have a small rounded shoulder to keep the belt & pin in place.

Wow! 1928? What model? Does it work OK?

It's a 1928 Southbend 9" Junior and it came out of a Massachusetts high school. I bought it in 1995 for $450 with all the gears & paperwork. It only had 1 collet with it and the belt was shot & I bought another one on ebay.

The cross slide tool holder "ways" are well worn & so it has some slop. The "longwise" bed ways still have faint cross-hatch marks on it, so it's okay. It works fine for cross-wise cuts as long as I take small incremental passes. Otherwise, if I want to take deeper cuts on large diameter pieces, I have to tighten & loosen the gib screws up as it traverses across the "cross slide".

For length wise cuts, I just tighten the toolrest gibs down & let'er rip. At the slow travel speed, it can make deeper cuts lengthwise & they come out really smooth.

You'll have to forgive me if I haven't used the right vocabulary. I'm an electrical engineer, not a machinist. I bought this to play with & it has indeed been a very fun tool to have. It's somehow very theraputic playing with it. It's also proved very handy at times fixing /making minor car parts, household items, hobby repairs, etc. I can even cut threads properly with it.

I'm impressed that you still have visible scraping on a '28 lathe. If the ways are good, everything else is fixable or replaceable. The height of the compound slide isn't critical in a lathe like this, so you could have it reground, lap it yourself, or put some of that plastic (whose name I never remember) on it.

You might even find a good complete apron on ebay for less than $200, but it sounds like you've figured it all out. There used to be a cartoon in the Sunday papers called "Out our way" that had an old machinist who could shim and finagle his lathe to get good work, but nobody else could even get it to work. Maybe you can be like that guy?

Does my heart good to hear that some old iron is still working.

I've enjoyed reading this topic.

I started using a Myford Super 7 and a Harrison 140 in secondary school. Wasn't keen on the Myford.

Engineering collage had a Harrison 140 with a hydraulic profile follower. It was a bit weird to get your head around with the tool post on the opposite side of the saddle.

The collage had mainly Colchester lathes. And one other I claimed as mine, see below.

Starting work in a quarries there was a wonderful toy to play with. A 108"x30' Broadbent. It was a beast, you could ride on the tool post. An 18 foot faceplate.

I left the quarry and went in to steelmaking.

The workshop had my old friend the Harrison 140 this one kitted out with a taper follower.

And one I'd seen before, a Czechoslovakian TOS. 20"x18'. The one at collage was a baby with a 10' bedway.

BTW I trained as an electronics engineer, but I have a habit of wandering off track a bit.

A good friend phoned me last week, they've bought a Harrison.

I cut my teeth on an old 9" SB about 65 years ago. MY current lathe is a Sheldon 11" that was built in the late 40's for the U.S. Navy. It has all the accessories available for it that were supplied as part of the Navy contract. It had been installed on a Liberty ship. It doesn't show a lot of use and is in very good condition. This lathe was built in the U.S.A. and if it were built here today, I would expect it to cost around $25000. There are Yahoo SB lathe groups on line that can be of help with any questions you may have.