Conditioning a lathe bed?

[KEW]

We all want our tailstock and banjo to glide effortlessly on the bed when loose and lock securely when locked.

I'd be willing to believe both of these trains of thought:

1) Maximize contact surface area by polishing the bed (and the bottoms of the Banjo and Tailstock) to a mirror finish.

2) Leave scratches perpendicular to the bed to give "tooth" for locking.

Which is right? Are there other options?

Does wax compromise the ability to lock securely?

Thanks!

 

[Christopher K. Hartley]

KEW, I share just my experience, Wax tends to cause slippage so problems do arise. I have used WD40 and steel wool to clean my rails and contact points then I wipe it clean. When I do that, I get great glide and good locking. As to the Polishing or Scratches issue, My Dad was a Machinist and I remember him saying that a good machined surface was one that was smooth free of scratches but not polished. That has been many years ago but I follow that advice today and it works for me.

We all want our tailstock and banjo to glide effortlessly on the bed when loose and lock securely when locked.

I'd be willing to believe both of these trains of thought:

1) Maximize contact surface area by polishing the bed (and the bottoms of the Banjo and Tailstock) to a mirror finish.

2) Leave scratches perpendicular to the bed to give "tooth" for locking.

Which is right? Are there other options?

Does wax compromise the ability to lock securely?

Thanks!

 

[waltben]

Lathe bed conditioning

I was once told that John Jordan uses Pam spray on his Stubby bed, spraying it on and lightly wiping the excess off. I tried it, but didn't see any significant difference to doing my usual. My Stubby is in my garage 'studio', so I do periodically have to clean off surface oxidation by either a few drops of light oil, rubbing with a Scotch-brite pad and then wiping off, or with TopSaver if it's from wet wood and heavier. I tried wax once (a long time back) and had to clean it off - it was too slick.

I've also a Jet mini that I use in a small shop in my basement and for demos. I've never done anything to its bed, but periodically get irratated at how sticky it is - it's not machined anywhere near as smooth as the Stubby's is. One of these days I may take a large stone to it and try smoothing it out some, just so everything slides easier.

Bottom line is that I guess wax just makes things too slick, but if you can see lines in the metal, it's too far the other way. A light coating of some kind of oil or protectant is what's needed.

 

[john lucas]

KEW Here are my thoughts. For the two to stick together things need to be flat and as large a contact area as possible. To slide easily they need to be smooth.
I've never done any thing to the bed other than wiping it down with WD 40 and some 4/0 steel wool. This is what John Jordan recommended. I haven't heard him recommmend Pam but I do know that some people use PAM to lubricate thier bandsaw blades for cutting green wood. This has worked well for all my lathes. I have tried Johnsons paste wax because I use that on my table saws and such but it doesn't stop the rust from woods like Oak and Cherry.
If you have trouble with the tailstock slipping I can make three suggestions. First is to lengthen the locking arm to apply more leverage. I don't think this is the best idea because you can damage the arm if you apply too much pressure.
Flatten the base of the tailstock. This requires a lot of time a some skill. You have to mark the bottom with dye, rub them together then remove the high spots very carefully. If not done correctly you can make it worse.
Make the contact surface of the locking pad larger. this is the easiest method and has proven very effective. I've done it on my Jet mini. Many lathes have a very small locking pad and it simply doesn't have enough contact area to lock the tailstock securely.
It doesn't require a lot of equipement to make a larger pad. I just took some metal I bought at the local Tractor supply shop and cut it down to fit the lenght and width. One for the lock and one for the area between the bed. I did flatten the thick piece with sandpaper berfore I screwed these toghether and drilled a hole for the locking lever screw. Do this just like you would plane a piece of wood. Hold a straight edge up and look for light. Mark these areas and very carefullly sand the high areas. You may have to lengthen the screw or counterbore a hole if the base is too thick. This gets trickier.
I did add a roll pin and spring to keep the tailstock locking pad aligned and pushed up to make removeal and replacement of the tailstock easier.

 

[MichaelMouse]

Of course, polished surfaces stick together real well if you're not careful, perhaps even when provided with a spray of oil, where the difference in choice is in viscosity and little else, I might add. That's the one thing we can rely on to give us an easy slide - lubrication. I go WD40, because it doesn't collect dust like something with lower vapor pressure like canola, olive, corn or "vegetable" (ever wonder what that really means?) oil.

The one thing we can use to give us a grip is friction, which is the opposite. It sounds like a conflict, but if the surface of the bed and the bottom of the banjo are properly lapped, with a cam that provides good resistance to backsliding, it can be done. Some cams don't have enough lift, in my opinion, to allow a lift and slide and still make a good seat. If yours is one and you're having troubles with grip, scatter some pumice on the ways and lock your banjo over it. Wipe later.

 

[KenN]

Kew,

My practice is much the same as the WD-40 folks except that I use a teflon spray - Tri-Flow. I spray it on the bed, slide the banjo around in the spray, and wipe the whole thing down with a paper rag. If the bed shows any rough spots, I'll rub with a Scotch-brite before wiping up the excess spray. It works as well on the lathe as on all other metal-to-metal sliding parts and the banjo stays put!

All the best,