Thread: leveling device

Graham,
I guess there are several features of this that are worth noting. For a start the level used is a pretty good one - I think it was something like 0.05mm per meter. This precision is very sensitive to slight inclinations. If you lathe was perfectly level then sitting on the cross slide might do, but this set up lets you compensate for any over all out of level that may be in the lathe.
The relatively narrow base width also means that local wear can be detected, where as on the carriage the wear might be bridged, and either not seen or seen but with less accuracy as to it's location or extent.
Measuring the V's with two dowels like that means that the working surfaces are being measured. Using a couple of parallels (depending on how they were placed) may mean that you are measuring an un-worn area.
The last point is that that set up is very flexible and can be adjusted to suit a number of machine geometries without lots of bits everywhere.

Michael

Hi,
I understand all parts of the jig except for one of the two bolts on the back on the jig. One is clearly right through the jig and rests on the rear way, but is the other one for?
Ewan

I can't recall that feature being explained, but I'd say it was a handle so that you weren't disturbing the adjusting bolt.

Michael

Originally Posted by GDD

which I didn't want to hijack.

Hijack it, I’d much rather it in one spot.

Second screw, more than one screw, elongated holes, etc. There’s nothing more sinister there going on, in that it’s just a roller bar that will suit several machines.

Phil.

So my question is - how is this better than just sitting the level on the cross slide and winding the carriage back and forward? l

It is short, so it can measure local deviations, convenient in that it has a nice surface to sit a level on and easy to adjust.

That tool is for machine survey, but you can also use it to level your lathe by placing it at the unworn ends of the bed. I had used the cross slide method, but when I made a tool similar to the one shown, I found errors in overall level I couldn't detect before. However that's with a very worn lathe so for most machines the cross slide method of levelling may be fine.