Revisiting the Old lathe’s bronze spindle bearings
Revisiting the Old lathe’s bronze spindle bearings

I think it’s almost two months ago that I used his old lathe and that was for making a drive spur for my wood lathe At the time I noticed that the spindle was a bit binding So tonight I will disassemble the spindle again and see if I can improve things Well it looks like I still don’t have the correct oil This oil seems to be drying out And, crystallizing There was a there was a bit of a oily drip stone down underneath the spindle Here you can see what’s left of that drip stone I was using that shell Tellus ISO 46 hydraulic oil But I clearly need to look for something els I find this very strange So the lathe has been sitting here doing nothing for two months Now the spindle is completely frozen up I can’t get it moving with one hand Yeah, there its is. It just broke free Took quite lot of force Let’s see if I can still disassemble this thing in like 5 miniutes or less I think my binding problems started again after I modified this ring on the front That keeps the spindle from moving forward There is still a lot of good oil here That took more than seven minutes I must be getting a rusty Although I did spend a minute or two looking for my tools This is the front bearing And, this looks like it’s copper oxide because it’s greenish 3 / 4 millimeters on the inside all the way round a little less at the bottom and And the whole bearing surface here is also green It also transferred a bit to the spindle Here’s the ring that’s rides up against this surface And it is also a bit green I don’t know if you can see this on camera I’m not sure if this is because of the wrong oil or because of a bad fit This is the ring that right up against the rear of the front bearing and look how dirty it got I already cleaned this surface The green copper oxide is mostly gone It looks like there’s a little…. It looks like there is some….. It looks like there is a bit of a layer of…….. Well, it can only come from the oil. That stuff is also on the side. Were the extra oil leaks out. The spindle started rusting again, even though I drenched it in oil The rear bearing looks pretty much the same as I left it the last time There’s one big difference between the front and the rear bearing T here is nothing riding up against this side of the bearing Disassembling the spindle pushed to the front bearing forward again I wonder if I should pin the bearing. Drill a few holes trough here and put in some grub screws Every time you disassemble, or every time when you hammer out a tapered arbor You risk moving the bearing forward And over time it gets looser and looser I’m going to scrape of this green stuff using this box cutter knife And when I’m done with this I will put it back together If anybody knows why this is happening, let me now put it in a comment Because, I just about had it with this lathe I want to be able to use it and not worry about the spindle To be continued……. probably

14 thoughts on “Revisiting the Old lathe’s bronze spindle bearings”

  1. Shoptime Fishing says:

    I learned a thing or two from this. Thanks!!!

  2. CurlyG65 says:

    I would fit some grease nipples and use highspeed bearing grease in the headstock, don't know about the bearing moving, maybe make a retainer plate that slides over the spindle and bolts into iron face around it.

  3. Sideways Wizzard says:

    Interesting issue, try ISO 32 Hydrolic oil. I wouldn't use grease, I don't think any old lathes ever used grease. I use Auto transmission fluid with an ISO 32 rating in my old Myford.

  4. hopper1 says:

    Plain 30W engine oil would be much better than hydraulic fluid. Think of the lathe spindle as if it were an engine crankshaft. Would you want to lube your car's engine with hydraulic fluid? Don't use automatic transmission fluid either. ATF is intended to, among other things, help a transmission's clutch packs bind together.

  5. xynudu says:

    The oil is reacting with the bronze bush. This can happen with some modern oil additives.

    Using plain mineral oil or automatic transmission fluid will avoid this.

    I use Dexron 3 ATF in my Schaublin 102 plain lathe bushes and have no problem. The front bush is steel on steel, and the rear bush is bronze on steel (same as yours).

    You don't need a heavy oil if the bushes are correctly adjusted.

    Also try Loctiting the front bush in place to prevent lateral movement.

    Cheers Rob

  6. georgewocosky says:

    It looks like oxidation from a combination of time / moisture / humidity . . . * If the bearings were very warm when last used , and the room where the lathe is was very cold; it could very well be condensation that caused this.
    Crystallization of the oil / grease is another matter . . . Under 'normal' conditions, it seems that merely replacing / replenishing the oil would be the right thing to do – ( almost any mechanism that is open to the environment will lose oil over time , & bearings are no exception ) Does the bearing oil fill area have a wick , or is it merely a hole that goes directly to the bearing ? GRAVITY would tend to pull the oil downward, * the thinner the viscosity of oil, the faster it will drain ! One of the differences between grease and oil is the type of detergent / soap that is added , which can also change viscosity, or the ability of the oil to remain as a 'film' on the surfaces . . .
    Was the oil in the filler cap GONE ? Is the oil in the filler reservoir also crystallized ? Normal practice would be to lube everything prior to using . . . * I concur with Xynudu . . . plain mineral or light machine oil would be the thing to use ! As long as the bearings aren't worn out, the oil film should remain on the shaft & bearing !

  7. LV_Woodturner says:

    Thanks for the update. Bummer about the bearings. Looks like reaction between the metals and something in the oil.

    As others have commented, can you get non-detergent engine oil in your local auto parts/hardware stores?

  8. Crafted says:

    It's galling. Like no lubricant. Is the bearing brass and not bronze? It needs to be oil-lite bronze or solid bronze with a lubrication groove.

  9. Batch562 says:

    Cool video!

  10. Jim Zivny says:

    Hydraulic oil is not the same as lubricating oil, different additives and properties. Also some hydraulic oils can react badly with some metals and the coatings used on metal s. The thin plating you pointed out in the video was probably eroded away from the base metal by the properties of the hydraulic oil.

  11. Sheila Walker says:

    Excuse me. The green, as chemistry 101 tells you, is verdigris. Acid reacting with copper in the bearing alloy. So your oil has acidic content, or heat is turning it acidic.
    Verdigris, or Copper Oxide, has several uses. A paint pigment, a fungicide, and a coating to prevent bronze from oxidizing further. It can also be used as a high grade polishing compound. It is not a lubricant.
    Change your oil to something other than low grade acidic sludge, or call your lathe a sculpture, stand it in the corner, and charge admission for people to come view it.

  12. Thomas D Harrell says:

    the brass is copper and zinc ok. The green stuff is the copper oxidation, maybe acid material or air. You said you were using hydraulic fluid. Hydraulic fluid is high detergent and acid. That would be my first guess. I would recommend to change to oil with no detergent a plain 30 weight oil or maybe 80 weight gear oil. try the 30 weight first and see how it does. I would make new brass bearings and go to 30 weight oil.

  13. Sherzod Ruzmetov says:

    Better use Mobil Velocite No 3.

  14. Paul Blackman says:

    The gunk will come off with paraffin and wire wool, looks like acid damage to me. Needs new bearings.

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