Fixing an old lathe with spindle "droop"

[awake]

My $0.02 - Whether you go with babbit or bronze, I don't think I would try to make the entire thing out of either. Rather, I would bore out the existing bearings and use babbit or bronze as a liner. This would be much less expensive on the bronze, and I think might give you a better / more rigid bearing for the babbit.

 

[Richard Carlstedt]

Late to the party here, But always looking for simple fixes.
Are both the bearing inserts (front and rear) the same ?
Can you reverse them ?
On the front bearing , can you flip it bottom to top ?
By moving the bearings around you may solve the drop .

On a side note, try to stay with Tin or Tin bearing alloys
Tin is by far the greatest bearing material there is due to it's extremely low friction and anti-welding characteristics

Rich
PS
Babbitt is a high Tin based Alloy-good stuff !

 

[MRA]

David Richards' 'Old Time Steam Powered Shop' series on Youtube has some good examples of babbitting bearings in-situ. He seems like a nice guy, too - very easy to watch. Also, your lathe maker seems unknown at 'Lathes.co.uk', which is quite an achievement given the number of entries there are on that site these days - you might like to send a pic to the site owner?
cheers
Mark

 

[MRA]

Here you go - here's the link:

 

[nurd77777]

Fine thick layer of Babbitt on that old steam shop bearing. Mine would be about that thickness in places if I go down that route. "Ye olde lathe"once had a capstan slide which I used as a Z axis in my Gingery Lathe/Mill impersonation. I've made lots of bits for the venerable old lump of cast iron. I did try and change the bearings round that's how I cracked one the lower ones are embedded and will probably need a good soak in diesel to budge. My bearing has a trust at each end . If I cast some Babbitt in a tin can with a tube down the center then machine the square bit, then bore out and split, that should be the way to go. That Alex Tiranti calls it bearing metal not Babbitt , I will have to phone them. Thanks all.

 

[MRA]

I've been having fun thinking about this. I wonder if you could mount a spindle on the cross slide and (difficult bit) get it spinning on-axis with where you want the headstock spindle to be. Then you could use it with some tool steel mounted in it to bore your new bearing it-situ - thus ensuring that the bearing is parallel with the ways on the lathe bed. I don't know if you have a tailstock - if you don't, it's a bit less critical where the thing spins, but at least you end up parallel to the bed.

 

[TSutrina]

I assume the shaft is not parallel with the bed and the likely problem is with the bearing close to the chuck. I also assume that you have a hole in the spindle shaft for a Morse taper. I also assume you have a Morse taper in the tail stock. The problem you have is to machine out the bearing block without a method of doing so.

I would start by lining up the tail stock dead nuts with the height of the back bearing in the head stock. Use the Morse tapers. Old broken Morse taper drill with the broken end made to join up with the end of a live center in a lathe tail stock. A collar could connect the two. Maybe you can come up with a better approach but this requires only making a special collar with a drill press. ID to fit the drill and the live center point short diameter The collar would have two set screws to engage the key way cut in the drill shaft, and a cutting tool can be mounted in the face of the collar. The bit is set to cut the OD matching the bearing. use the tail stock to move the cutter. Your using the lathe to machine itself. Your choice of bearing that can fit into the casting, roller, angular contact ball, or journal bearing. The basic same approach can be used to machine the rear bearing. If you use bearing you will have to keep the lubrication in and dirt out. Make or purchase shields.

 

[TSutrina]

I looked up Greenwood & Batley Ltd on the 'Vintage Machinery' organization site Didn't find your lathe but found two that may help others on how it is likely built.

http://vintagemachinery.org/mfgindex/imagedetail.aspx?id=7405

http://vintagemachinery.org/mfgindex/imagedetail.aspx?id=6491

May I suggest that you contact the organization to add your machine to their list.
If you have an image that you think would be appropriate for this manufacturer, please contact the Site Historian. http://vintagemachinery.org/about/contact.aspx

 

[TSutrina]

The picture doesn't show a tail stock but still if you can a line up the spindle shaft with the tool bit holder for a boring bar then your in business. Options is to machine hard wood journal bearing that are well oiled for doing the machining. Can replace the back bearing with a hard wood journal bearing fitting tight in the OD and journal ID for a shaft. Rex Krueger on YouTube builds a wooden lathe with wooden pulleys. Block of hard wood with a hole partially through attached to the tool post give you the second bearing and moving the carriage a means of cutting. A collar is used to hold the cutting bit and adjust it for depth and with shims and two set screws for diameter. The v belt will take some misalignment, cutting depth. The shaft is nothing more then round bar stock steel. The same approach can be used to cut the rear bearing using the front bearing made from hard wood for the effort.

Please contact the vintage machinery organization before any more alterations are made. See if this is worth adding to a collection. It appears that some changes have already been made. You could get a newer lathe in trade.

 

[nurd77777]

Hi TSutrina and MRA the reason why I hold on to this machine is that its a big lump of cast iron and I have two large chucks , if I were to get a similar machine I suspect it would be floor mounted and weigh a ton. Sorry it does not have any Morse tapers. I am not sure where to mount a boring bar but I have lots of soft cast iron to use as make shift bearings. Driving a boring bar would not be too much of a problem as there are lots of geared electric drills available , I saw one design which actually advanced the cutting bit by knocking a ratchet driving a lead screw as it rotated. I will contact the archive guy, no changes will be made until after Christmas. Be of good cheer Keith