David, not an expert but having the lathe level helps when setting it up. As you say though if there is no twist in the bed and no distortion then the lathe will still work at an angle. There are slant bed lathe which are definitely at an angle front to back but probably still levelish lengthwise. I think getting paranoid about level is unnecessary. When I was briefly in the Merchant Navy the lathe in the engine room was rarely, if ever, level. Come to that you had to hang on to it just to keep yourself level sometimes!

John

There are slant bed lathe which are definitely at an angle front to back but probably still levelish lengthwise.

Slant bed lathes are leveled front-to-back using a fixture held in the turret that puts the level errr…. level.

Sometimes this is provided with the machine as part of the original equipment, sometimes the installation technician brings the factory tool along with him (and takes it away again) or, in my case, you make one when you get a second hand machine.

When (reasonable quality) lathes are manufactured, the alignments are set with the bed set in a known condition. Setting the bed back to that known condition on installation should, therefore, bring all the other alignments back to the values shown on the inspection record. In the greater (industrial) scheme of things, a precision level is cheap & easy to use, so using one to set the bed level is easy for both machine builder & end user to get to a known condition.

A 0.05mm/metre level can be obtained from Ebay from £40-ish (Item 272295866038 for example), which isn't a great deal for a precision measuring device.

Doubtless there will be other posts along shortly extolling the virtues of "Rollies Dad's Method" (whoever Rollie was ?) to set up a lathe & decrying the use of a precision level in the home workshop – to each their own !

Nigel B

The engineering community need to invent a new word for levelling a lathe when they don't mean levelling it.

Like when the first cave man started to knock through an extra door hole but had a tea break after doing the top half. He got tired of explaining to everyone that it was half a door that he hadn't got round to finishing so invented a new word for it which made it much simpler.

Why would you ensure that there was twist in your bed? That's confusing!

May I refer you to Chapter 9 of Tubal Cain's (pen name of T.D.Walshaw) book Workholding in the Lathe (Workshop Practice Series 15) where he goes into mounting a lathe, and then the reasons for, and how, to set up the lathe.

Peter G. Shaw

Unless your comment was tongue in cheek, Ian obviously had a sausage fingers moment and typed 'now' instead of 'not'

The Slant Bed lathe (example Willson Lathe Company of Halifax) was a means of using a larger swing over the bed, the spindle being set further back.

Nevertheless the bed is "level", albeit at a downward inclined angle front to back. (Hence jig Nigel B mentioned earlier above).

The axes of a lathe need to be set up true to each other, not of necessity in relation to any other plane. We have called it " levelling", Set true might be a better term?

Hello David Thompson.

I do have some knowledge on the subject. Not a lot, I admit, and probably not as much as many of the luminaries hereabouts.

My posting was intended to be taken with a certain degree of levity. The subject of lathe set up and levelling has been done to death and invariably results in a bun fight between respective camps on whose method us the best.

My words were intended as a bit of a laugh, a sigh and a “here we go again…”

I’m sorry if that didn’t come across.

Carl Wilson.

Nigel

Is Rolly's father a different person to the Rollie you mentioned in your first reply (third not sixteenth post) to this thread?

Ian P

No need to be like that Nigel. I was just answering Alan's question. Not everyone wants to spend out on a precision level that they might use only once. The object of "levelling" a lathe is to ensure that it turns parallel. There's more than one way to skin a cat.

Russell

Hoppers post is really heartwarming. I now know two people (including myself) who realise that there is absolutely no need whatsoever for a lathe to be level. The only requirement is that tha ways are flat and true in and on one plane rather than twisted or under torsion. If you doubt the veracity of this just take a look at a CNC machine with the bedways at 45 degrees to the vertical. There ain’t no way that position can be called level.