Help me ID and date my Cataract bench lathe.

I bought this lathe today. It seems pretty grotty on the surface but I think that fundamentally it's in reasonable shape. I'd really appreciate some help with dating it and any other info that might be handy to have.

Here's the pics of everything I've got. Unfortunately I don't have any of the original drive bits but it did come with a really neat 0.5hp miniature variator which I'll probably re-employ as a drive unit. Pics of that later.

One more pic showing the headstock end, and another item that came with the lathe that I can't figure out of it belongs or not.

Anyone know what it is - apart from "broken"?

Does anyone have a cross-section or exploded diagram of the headstock? What's it that controls axial end-float?

Looks like a size 37, which means Cataract No. 3 collets (3C) and 7 inch swing.I will guess a date of around 1910-15. It has the common 32 inch bed without rear T-slot. I don't know know what the extra piece is.

Tony has a lot of pictures, including a headstock section. There is a fiber washer at the right end of the pulley and a ball thrust bearing at the left end. The pulley has a threaded adjustment for end play. The washer has to have a tiny gap, of course. On the first Cataract I owned, I fitted a Torrington needle thrust washer to the right end of the pulley so that I could have a slight preload and zero end play.

The tailstock taper is "Cataract" and only Hardinge used it, so forget buying new centers and drill chuck shanks unless someone reamed it to 1 Morse. Similarly, the spindle nose is Hardinge No. 3 taper and original tooling is very scarce. The only good news is that 3C collets are easy to get, new or used.

When you take it apart, be careful with the spindle bearings. They are hard cast iron and fragile.

Larry

Larry thank you for taking the time to respond, especially for the tip about the headstock bearings. I'll clean up the spindle end and remove the brass bearing end cap. I had a peek underneath when I took the photo and it seemed to me that the bearing was a bronze colour, so they might not be original. I'll check it out properly this evening.

It has a chuck fitted as in the pic but the chuck is a wrecker. Also the barrel is fairly rusty so I'll have to appraise that and decide whether to recover it or make a new one from a bought-in MT1 quill. I'd rather the machine was more usable than original. I'll keep the original quill with it of course.

I'll check out the pics on Tony's site.

This is a 5C spindle machine but the breakdown is the same. The thrust bearing
is adjusted via the spaner holes in the threaded end piece. You need to relax
the setscrew that locks the adjustment before moving this.

Serial number on this headstock is F-106 btw.

When taking the pulley off the spindle, mind the double set screws. Don't just back off the ones you can see. Take them all the way out and see if there is a second screw under each one. The two actual locking screws have tapered dog points that engage holes drilled in the spindle. I can't recall if the endshake adjustment locking screw is a single or double. It is always safer to remove all the set screws on a Hardinge product when taking it apart.

And don't lose a screw. Hardinge used some strange thread sizes, so you get to make your own if one is damaged or lost. The thread in the bed feet is 1/2-12, rare in the USA, but not so bad in the UK, except the USA form is 60 degree. They also liked 30 and 26 TPI, so measure and don't guess.

I had a Cataract head that had some homemade bearings made out of brass. The spindle journals were scored badly, much worse than on any of my heads that had the original iron bearings. Those wool felt pads and wicks really worked well to keep neglected bearings oiled. These things are old, and many have suffered from poor maintenance and improper replacement parts.

Larry

I got it successfully stripped down yesterday evening. Everything is in very reasonable condition except that the collet retaining pin has been damaged (there is corresponding damage on the threaded end of one of the 3c collets. The top of the pin has been driven outwards into the cast iron bush and cut a shallow groove. I'll make an internal lap to remove any high spots on the bush. Does anyone know how the pin is retained? This one does not move or wobble and I haven't tried to punch it out, my feeling is that it should probably be a screw-fit somehow.

The rear bush is a bronze replacement and is very nicely made with a new wick fitted. The front bush is original cast iron. The spindle bearing ways are excellent and sport no grooves or ridges aside from the damage from the pin.

It has always amazed me of the quality and craftmanship that went into a Cataract lathe. I'm really glad that I don't have one. Why you ask? Because once I had it restored, it would be way to pretty to use.

I've though about the cost and work that would go into reproducing parts for those lathe. Those cast iron bearings would probably be the worst. I think that if you took a drawing into a well equipped shop and asked for a quote on a pair, they'd be well over $2K. And most shops would struggle with them.
JR

This collet pin predates the often-seen setscrew type in the newer hardinge machines.

Yours, like mine, is simply pressed into the spindle. Yep, the entire spindle has to
come out to change that item. Mine had sort of a diamond-shaped staking over
the outer surface of the spindle, but in the end I simply pushed it out into the
spindle bore, made a new one out of unhardened drill rod, and pressed it in from
the outside. Extra tap with a punch to be sure it was below the top journal surface.

I have replaced a few collet keys in various watchmaker lathes and I think I did one in a Cataract spindle. I have installed several similar keys in Hardinge lever collet closer spindle caps, which are of similar configuration. My recollection is that the spindle key is rectangular, and longer than the diameter of the cylindrical portion, so it has to be installed from inside the spindle. The outer portion of the key hole in the spindle is square, probably filed before hardening.

I make the replacement key from unhardened drill rod (silver steel in the UK). I make the cylindrical portion a very close sliding fit in the spindle hole and leave it long enough to protrude above the journal. The key has to be inserted from inside the spindle bore, which is why you don't want a press fit.

To prepare, I select a solid body collet shaped arbor (male center or Morse taper adapter, for instance) rather than a thin-walled collet because it will have to take a pounding. I make sure the keyway depth is normal for that collet and then make a narrow steel shim to fill the gap between the bottom of the collet keyway and the new key. The shim is bent down the back of the arbor to keep it in place. I make a trial installation of the key and arbor to make sure the key fits and the shim holds the key firmly against the bore of the spindle. Then I put a drop of Loctite on the key and reinstall the key, shim and arbor. I use a cross pein hammer to rivet the key into the corners of the square. Then I remove the arbor and wash out the excess Loctite from around the key inside the spindle. I use a fine file to make the top of the key flush or below the journal, polish it and call it done.

Larry

Thanks Larry, Jim and JR.

For sure, the build quality is impressive for a 100yr old machine.

I'm going to knock out the pin and look at making a replacement. I do have a 3c/MT1 collet with a solid body so I might well use that as an anvil to stake the pin so it can't back out of the hole.

I'll do some pics and write it up, of course.

New pin is made an fitted.

I punched out the old pin which didn't give much resistance. It was made from round with a couple of flats milled in it. Must have been a loose fit because they have tried to increase interference by beating the tail end of it out of round. Clearly that didn't work because it managed to back out of the hole and score the bearing.

The hole in my spindle is plain round with no facility for staking so I made a pi to fit from the inside. I made it from a 12.9 bolt (similar to grade 8). I turned the 1/4" long stem to a press fit in the hole but with 1/2 degree taper on the first 1/8". I'd measured the groove in the collets at 1/8" wide and 0.050" deep from the OD so I made the key top 0.040" tall and 0.110" wide. I held it in a drill chuck to allow me to grind a gentle radius on the top of the key.

Once it was made I knocked up a tool to press it in from the bore. I had enough lead-in on the pin shank to pinch the end in the hole then I used the wedge tool to gently bar the pin home, with a small hammer tap to seat it.

A couple of things I have noted on my lathe that I am wondering about.

1. The Lathes website states that the Hardinge taper nose has 80-degree angle slots on the retaining tee slot. Mine is straight as best I can measure it. Is this normal for the early spindles?

2. The dog point screws in the 3-step cone pulley are 5/16" - 26tpi. I can find this as a British thread size (cycle thread and brass thread) but not as any American standard which I would expect it to be. Can anyone enlighten me on what American thread this might be?

That lathe pre-dates the adoption of standarized threads. The thread you mentioned, *is* the correct thread,
60 degree form.

1. Here is the patent, issued 28Jul1908: Patent Images

The claim specifies two short spiral grooves extending in both directions from a single longitudinal groove.

2. I warned you in post #8: "And don't lose a screw. Hardinge used some strange thread sizes, so you get to make your own if one is damaged or lost. The thread in the bed feet is 1/2-12, rare in the USA, but not so bad in the UK, except the USA form is 60 degree. They also liked 30 and 26 TPI, so measure and don't guess."

The SAE and ASME standards were not established when the first Cataract lathes were built, so it was "Wild West" and "anything goes" for screw threads back then. But the 60 degree thread form was kind of standard.

Larry

You did indeed Larry, it's not that I have lost a screw so much that the pulley only had one fitted, and a shop-made one at that! I'll either make a pair or else buy some BSC/BSB set screws and suffer the 55 degree thread form.

I do only have the one screw for the bed feet, but a 1/2" Whitworth bolt fits those just fine.

I'll set about measuring the slots with a little more care. Perhaps the spiral is so shallow it's only a few thou over the length.

Here is a picture of a typical 37 spindle nose. You can see the top of the T-shaped slot is bent to provide a cam action with the pin in the chuck bore. Think of it as a very short piece of a screw thread, with the pin acting as a piece of a nut thread.

The dog points are tapered on the pulley screws. The single screw is from the same 37 headstock to show the tapered dog point. The screws are slotted and hardened. The third picture is of all the screws from an early 57 headstock. The medium length screw is for the end play adjuster. The two long screws lock the pulley to the spindle. The two very short screws fit on top of the long screws and fit nearly flush with the pulley surface. Hardinge also used double set screws in other places.

The left bed foot is fastened to the bench with an ordinary hex head cap screw and flat washer. The right bed foot has a headless screw that just keeps the bed from swivelling.

Larry