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Peerless 8mm lathe primer info?


SSH

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It's 100% ok for plain bearings to get warm in use. In fact many old ultra high precision machines were run for 1 hour or so before being put "on line" as they were adjusted to run at that temp.

Synthetic automobile oil is an old and contentious subject in horology. I remember talking to a tower clock guy years ago who had gone to Mobil 1, and then reserviced a number of clocks for free after finding that the oil turned abrasive after a certain length of time. I haven't been able to find literature on it recently but there was some 15+ years ago.

Auto oil is changed on regular intervals in addition to being filtered. The demands, as measuretwice spelled out, are very different. In a plain bearing watch lathe the oil goes in and goes out- "total loss". So really anything relatively thin will work. In a larger machine it's an issue, as motor oils are designed to keep contaminants in suspension to be grabbed by the filter, and most machine tools don't filter their oil. Contaminants fall out in the sump- which won't happen with a detergent based oil that keeps things in suspension.

But back to watch lathes- almost any oil is ok, sewing machine oil is great, iso 10 or 20 hydraulic oil, awesome, 3n1 fantastic, Hoppes gun oil, killer, just no WD40.

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Thanks guys... Guess I didnt know I was kicking over a hornets nest with the oil question, but maybe I shoulda..... 

BTW, I know several of you said mineral oil, which I'm assuming is because that's what was available when the lathes were built. That's fine, but I'm wondering if the PDMS (polydimethylsiloxane... Silicone oil) I use on my other machines and firearms is safe for whatever the headstock pulley is made of? Its pretty great stuff for shear situations. But not everything is compatible with silicone and I'd be wary to find out the hard way.

 

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10 hours ago, nickelsilver said:

Synthetic automobile oil is an old and contentious subject in horology.

It might be a bit like some guys modifying cars.... tell them its made out of aircraft billet and the price doubles but they'll turn their nose up at 6061 AL  :D  Afaik there is no advantage to a synthetic oil over regular mineral oil until the temps get over 135C, and if you're getting your lathe than hot you've got other problems.  I've not heard anyone advocated synthetic oils for machine plain bearings, some very exacting like say Schaublin or Jones Shipman, as it just doesn't get hot enough to need it

 

I agree with you, a slow speed, well made plain bearing is going to be forgiving so its all good.  Of the many I've had apart, lots over 100 years old, I've only seen one that was destroyed and pretty sure it was just abused/not oiled

 

 

Edited by measuretwice
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If you are wanting a good book on the maintenance of the lather I recommend Archie B Perkins book 'The watchmakers Lathe and How to Use It', not cheap buy very useful, or for a cheaper book that is useful but more limited Donald de Carle's book 'Thw Watchmakers and Model Engineers Lathe'

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If you are wanting a good book on the maintenance of the lather I recommend Archie B Perkins book 'The watchmakers Lathe and How to Use It', not cheap buy very useful, or for a cheaper book that is useful but more limited Donald de Carle's book 'Thw Watchmakers and Model Engineers Lathe'

Got them both:)


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Thanks guys. Both books are on my wish list. I was curious about the pin b/c when the headstock was apart I noticed the pin was a tiny bit proud of the surface. No groove to turn it but it was obviously ground smooth. I was just debating what (if anything) I should do about it. It seems like the pin runs just at the back edge of the bearing but I'm not sure if its in the bearing or not.....

Thanks again

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It maybe be that what your feeling  a slight line or groove where the pin comes through the shaft, but that the surface of the top of the pin is not actuall proud of the shaft, i.e. its concentric and the same diameter.  If it was sticking up, I'd think the bearing ID would be likely be a mess.  If you have machines, the easiest way to tell is to put the shaft between centres and indicate the pin to see if its proud. 

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Sadly I got rid of my larger lathe last year, but no need to spin it. I pulled the headstock out to check it today and it turns out the pin is actually loose. Which explains both it not marking the bearing. 

I'm sleeping on the issue tonight but barring any suggestions from the experts here, I think I can formulate a good plan to install a new pin.

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On ‎11‎/‎16‎/‎2019 at 6:35 PM, jdrichard said:


Not sure but a synth does not break down under heat. Seems reasonable, and it does work well.


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   right you are,  but  select lube oil VISCOSITY  in relate to the clearance fit.  it is in the "machinery hand book"  vin

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On ‎11‎/‎17‎/‎2019 at 6:39 PM, nickelsilver said:

It's 100% ok for plain bearings to get warm in use. In fact many old ultra high precision machines were run for 1 hour or so before being put "on line" as they were adjusted to run at that temp.

Synthetic automobile oil is an old and contentious subject in horology. I remember talking to a tower clock guy years ago who had gone to Mobil 1, and then reserviced a number of clocks for free after finding that the oil turned abrasive after a certain length of time. I haven't been able to find literature on it recently but there was some 15+ years ago.

Auto oil is changed on regular intervals in addition to being filtered. The demands, as measuretwice spelled out, are very different. In a plain bearing watch lathe the oil goes in and goes out- "total loss". So really anything relatively thin will work. In a larger machine it's an issue, as motor oils are designed to keep contaminants in suspension to be grabbed by the filter, and most machine tools don't filter their oil. Contaminants fall out in the sump- which won't happen with a detergent based oil that keeps things in suspension.

But back to watch lathes- almost any oil is ok, sewing machine oil is great, iso 10 or 20 hydraulic oil, awesome, 3n1 fantastic, Hoppes gun oil, killer, just no WD40.

   oil does not "turn abrasive".   it conducts materal ( dirt,  metal particules)  thruout the clock.  hydraulic oil is not comcidered a "lube oil".   you can find this information in the Machinery Handbook.    

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18 minutes ago, vinn3 said:

   oil does not "turn abrasive".   it conducts materal ( dirt,  metal particules)  thruout the clock.  hydraulic oil is not comcidered a "lube oil".   you can find this information in the Machinery Handbook.    

Mobile DTE series of oils are "hydraulic" oils that are commonly used also in machine spindles. Here I buy from Motorex, their Correx HLP line, which is great for machine spindles, is "hydraulic", and specced for use in hydraulic systems and plain and rolling bearings.

 

I don't know the full story on Mobil 1 going abrasive, it was about 20 years ago; I did look it up back then but can't find anything now. The fact that the fellow re-serviced a number of tower clocks made it seem pretty legit, but in poking around I see that a number of clockmakers recommend it these days. I think the issue in the clocks is the very slow moving components, and long interval between cleanings. In a lathe spindle I doubt there would be any issue at all.

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8 hours ago, vinn3 said:

  hydraulic oil is not comcidered a "lube oil".   you can find this information in the Machinery Handbook.    

????

  You read this in Machinery's Handbook?  What machinery's handbook says is mineral oil is the most versatile and common lubricant.   As posted early, that is what hydraulic oil is, is clean mineral oil without much in the way of additives (like motor oil has).  Its one of the most common lubrication used in machine spindles and transmissions and is an excellent choice for plain bearings

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1 hour ago, measuretwice said:

????

  You read this in Machinery's Handbook?  What machinery's handbook says is mineral oil is the most versatile and common lubricant.   As posted early, that is what hydraulic oil is, is clean mineral oil without much in the way of additives (like motor oil has).  Its one of the most common lubrication used in machine spindles and transmissions and is an excellent choice for plain bearings

    i don't use mineral oil.  it is antique.  i use synthetic  and muti viscosity oils.  hydraulic  in a press.  i have delt with " oil engineers"   AND i don't intend to argue  further.   vin

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Hey all. Just a quick update. I replaced the pin in my headstock successfully. It was actually pretty easy. I don't expect any additional problems from it at this point. My only lingering question (and yes, I shoulda asked before I did the work) is how far the or pin normally extends into the bore? Since mine was damaged there was no way to get that measurement. Im not sure how consistent the keyway in various accessories are, so I set it up so the pin has about .008-.010" clearance to the bottom of the keyway. If one of you has an inside bore gauge would you be kind enough to measure the gap between the pin and the opposite side of your headstock? That would give me a good reference measurement to compare to.

Thanks!

Edited by SSH
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Hey all. Just a quick update. I replaced the pin in my headstock successfully. It was actually pretty easy. I don't expect any additional problems from it at this point. My only lingering question (and yes, I shoulda asked before I did the work) is how far the or pin normally extends into the bore? Since mine was damaged there was no way to get that measurement. Im not sure how consistent the keyway in various accessories are, so I set it up so the pin has about .008-.010" clearance to the bottom of the keyway. If one of you has an inside bore gauge would you be kind enough to measure the gap between the pin and the opposite side of your headstock? That would give me a good reference measurement to compare to.
Thanks!

Can we see a picture


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Here's a few quick pics of the basic setup, the newly installed pin, and me measuring the clearance between the pin and opposite side of the headstock bore with a small bore gauge (ie insert bore gauge into headstock and expand until it just touches the pin on one side and headstock bore on the other). That would be the measurement Id like to duplicate on a lathe with an original pin.

IMG_20191203_173202358_HDR.jpg

IMG_20191203_173634151.jpg

IMG_20191203_173026077.jpg

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