Select 816 B Lathe Acquired

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The pin on the bull gear is the only 'key' to allow the cone pulley to drive the spindle. Pull the pin to engage back gears, push the pin into the cone pulley hole with the back gears out for direct drive. The cone pulley should be a rolling fit on the spindle, usually bronze bushed. Maybe the previous owner ran it in back gear all the time and did not oil the pulley. The 'set screw that does nothing' is for oiling the cone pulley to spindle when running in back gear.

Again, this is a South Bend clone, instructions would be in HTRAL.

John
 
Hi Danuzzo,

Sorry I mistakenly thought you were referring to the headstock bearings.

At least you can now get at them to clean and re lubricate them with oil.

That pulley should be a good fit on the shaft.

You were correct. I was initially referring to the bearings; but, when I noticed all the play in the pulley to spindle fit, I decided I needed to tear it down to have a look.

Is it possible that the loose fit may be designed for proper engagement of the back gear? Like I say, the parts diagram does not show any kind of bushing. It certainly is not worn. The surface is too regular. Made of what appears to be cast iron by the way.
 
Shopshoe, cannot get at it from the back. It would have to be from the front in the cavity between the race and the headstock casting. You can kind of see the cavity in the last photo. I will keep you all posted. going to the bearing supply house this morning.

John, the bearing house has bronze bushings. Will see if they have any the right size. What does HTRAL stand for?
 
HTRAL: The previously South Bend book "How to Run a Lathe". The cone pulley needs to get oiled very time you run the lathe in back gear. South Bend later changed to a special grease that lasted about a half year because they were seeing damage from folks not oiling the spindle and/or back gear shaft. Lots of discussion of this on South Bend forums such as groups.io, or the one on Practical Machinist.

From your photos, looks like roughness inside the cone pulley bore from lack of lubrication.

Your roller bearings don't look too bad. I'd leave them alone, try oil lube and proper preload. I have several old late 1940's horizontal mills with similar bearings. Not nearly as nice looking as yours but still running fine and cool with proper preload...

John
 
Thanks. Yes, I am aware of the great debate between oil and grease for the spindle bearings, most going with oil. However, I do not have the manual, and there are grease (I guess they could be for oil) zerk fittings in the headstock on each end of the spindle. There are numerous oil fillers on other parts of the lathe, outside of the headstock. Also, all the evidence I observed appeared that the bearings were greased on this used lathe, not oiled. There is a leakage of excess grease that came from the inboard and outboard spindle ends outside and inside the headstock.

If oil is the proper lubricant on this lathe, is there any way to switch over without taking the spindle off and cleaning all he grease?

The lack of sight glasses on the spindle bearing housings makes me think the intended lube is grease.
 
Alright, went to the bearing house and they recommended a machinist who I met with today at his shop. He said the bearings looked good. He concluded that the cast iron of the pulley had a built in collar on the outboard end that had worn out, and that a bronze bushing had to be inserted. I convinced him to do it while I watched.

He had a nice Graziano lathe that he bored about 1.5 inches into the pulley where the shoulder was originally. He then made a bronze bushing that he press fit. He also cleaned up the spindle with a light cut in the area that makes contact with the pulley bushing. He said to keep that oiled through the set screw in the pulley because lack of oil is probably what caused the wear in the first place. That Graziano and the machinist were impressive.

I cleaned up the bearings. I will reinstall everything after I get the rear motor drive pulley shaft in the headstock off to replace the belts, and then put it all back together cognizant of properly adjusting the preload. I certainly hope it goes smoothly.

Thank's everyone for your help.
 
Hi Danuzzo,

Sounds like you are well on the path to getting the lathe back in action ! Lubrication is very important, too much is far better than too little. I make a point of lubricating everything that needs oil every time I use the lathe, which often can be twice a day.

I thought that I'd made a comment earlier the the pictures of the bearings showed that they looked good, anyway you've now had it confirmed.

As far as preload is concerned, when you have the spindle re-assembled, adjust the spindle so that it rotates freely without any play, then carefully increase the tension until you feel it just start to tighten. Stop at this point, lubricate the bearings and run the spindle for ten minutes and check that they are not hot. Just warm is about right. If they are still cold then add another sixth of a turn and recheck. You might find that you have to do this two or three times as the oil get distributed and the bearings settle.
 
BaronJ. I am very pleased that your assessment of the bearings was correct. The smaller rear bearing was a little over $40.00. Unknown as to the front bearing which is larger since it was never removed; but, it would have been more money.

Now that I have taken it apart one, it should not be too difficult to replace the bearings at a later date, if necessary. The only issue was going to be removal of the races from the headstock, which I am fortunate i did not have to do.

I will continue to update this thread. Thank's, again
 
Got all the belts off. Will buy new ones tomorrow in hopes it will all be back up and running tomorrow.

Another issue. As you can see in my initial post, the 3 jaw chuck only has the outside set of jaws. Are currently available inside jaws interchangeable? In other words, if I find jaws for a 5" chuck, should they fit on my chuck, or are they individually tailored to a specific brand?
 
Another issue. As you can see in my initial post, the 3 jaw chuck only has the outside set of jaws. Are currently available inside jaws interchangeable? In other words, if I find jaws for a 5" chuck, should they fit on my chuck, or are they individually tailored to a specific brand?

As you will see, the jaws are numbered 1, 2 and 3 but will also have a set of numbers identifying with the internal scroll inside the chuck. So I seriously doubt that you can get a matching internal set.
I may be wrong but it looks like a new chuck which has to be fitted to a backplate which fits the thread on the spindle 'nose'

In any event, the probability is that the chuck is worn for any number of reasons and should be replaced to give you a reasonable accuracy in the future. There is a lot of ballyhoo about re grinding chuck jaws.
As far as my experience goes, regrinding will accuracy at ONE dimension.
I haven't dismissed the possibility of having 'soft' jaws. They have to be recut generally but are most useful where extreme accuracy is required.
Theoretically, I have two self centring chucks for my lathe- different makers-- and the jaw sets are NOT interchangeable. I tend to have one kitted 'each way'- and then I have a most useful self centring FOUR jaw chuck- on both my lathes. Again, I have soft jaws for my Sieg C4 but have been unsuccessful for either Myford chucks.

I wish that I could be more helpful

Norman
 
As you will see, the jaws are numbered 1, 2 and 3 but will also have a set of numbers identifying with the internal scroll inside the chuck. So I seriously doubt that you can get a matching internal set.
I may be wrong but it looks like a new chuck which has to be fitted to a backplate which fits the thread on the spindle 'nose'

In any event, the probability is that the chuck is worn for any number of reasons and should be replaced to give you a reasonable accuracy in the future. There is a lot of ballyhoo about re grinding chuck jaws.
As far as my experience goes, regrinding will accuracy at ONE dimension.
I haven't dismissed the possibility of having 'soft' jaws. They have to be recut generally but are most useful where extreme accuracy is required.
Theoretically, I have two self centring chucks for my lathe- different makers-- and the jaw sets are NOT interchangeable. I tend to have one kitted 'each way'- and then I have a most useful self centring FOUR jaw chuck- on both my lathes. Again, I have soft jaws for my Sieg C4 but have been unsuccessful for either Myford chucks.

I wish that I could be more helpful

Norman

Hi Norman,
Cromwells are the people to try for soft jaws. I've got and use some modified ones with great effect. I'm sure that I posted a picture on here recently.

18-02-2020-002.JPG
18-02-2020-003.JPG

The original soft jaws have replaceable ones screwed on to them.
So I can just replace them as needed.
 
Got all the belts off. Will buy new ones tomorrow in hopes it will all be back up and running tomorrow.

Another issue. As you can see in my initial post, the 3 jaw chuck only has the outside set of jaws. Are currently available inside jaws interchangeable? In other words, if I find jaws for a 5" chuck, should they fit on my chuck, or are they individually tailored to a specific brand?

Hi Danuzzo,

See my post above !

Jaws soft or otherwise are unique to a particular chuck and manufacturer. A single manufacturer may use a different scroll across the same size chuck depending upon the accuracy specification. So you must get the correct ones ! But once you have the dodge that I have used in the pictures above is well worth doing.
 
I think that oil in those bearings should be avoided, since oil on a spinning part will get all over things around it, would have to keep oil supplied over time, and there is a V-belt in there! Sure do not want oil mist to get to that belt! Grease is used on probably 80% of the tapered roller bearings in the world. I have been a machine design engineer for over 40 years, recently retired, and can think of only one instance where I have seen tapered roller bearings in an oiled system. all others were greased.
 
As to the chuck, it is in very good condition. It is also very accurate. That is why I would like new jaws for it, as opposed to another chuck. The soft jaws idea may be a worthwhile option that I will research further. Thank's BaronJ and Norman.

As to the grease on the spindle bearings, that is what I will continue with because it appears that this lathe was designed with that in mind. The overheating could have been due (I guess) to all the old gummed up grease around the bearings. We will see.

As to the Logan 816 lathe, I just looked at some photos, and there is a similarity in appearance. Thanks, David. I will certainly delve into this deeper.

As to the link, BaronJ, I checked that out before I bought the lathe, and it helped sway me into buying it. Thanks.
 
If your chuck brand can be determined and the scroll/jaw/body numbers are visible and correct, try contacting the manufacturer of the chuck and see if they will produce a set of external jaws for you. I know Pratt and Burnard used to offer this service. Costs nothing to ask.
RonW
 
If your chuck brand can be determined and the scroll/jaw/body numbers are visible and correct, try contacting the manufacturer of the chuck and see if they will produce a set of external jaws for you. I know Pratt and Burnard used to offer this service. Costs nothing to ask.
RonW

No name brand; but, there are numbers. As to manufacturer, only says made in England. Good idea. I will try to find it by the numbers.
 
No name brand; but, there are numbers. As to manufacturer, only says made in England. Good idea. I will try to find it by the numbers.
If it says made in England then it's a fair bet it might be a P&B chuck. Does it have about a 3/4" circular depression in the face where a decal might have been. All my 3 P& B's have this but the decals have long since disappeared. Contact them and supply the numbers. They'll tell you if they can replicate the jaws.
RonW
 
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