Levelling A Lathe

I also question the use of hockey pucks here, too soft and pliable. If your cement floor is stable, a soft aluminum pad would be preferable to rubber for contact with the floor.
In my case, the thin aluminum pad was cut oversized so that I could use it as a feeler gauge. I check the tension on each of the 8 feet by tapping the aluminum pad sideways with a hammer. My lathe has not 'walked' the slightest bit in 2 years of use.
 
OP called his pads hockey pucks but seem to be cast iron. It's common to call them hockey pucks...not sure I'd play the game with these though.

I used real hockey pucks for my Rockwell 11". Not the heaviest lathe but around 1100lbs. with cabinet full of tooling. Machined a thick alum washer a bit smaller than puck OD. Holds level/alignment well and dampens some vibration.
 
To all who have replied thank you. I am sorry if I have confused some respondants by calling the small discs that are placed under the levelling screws "hockey pucks". It was my impression that was what they were commonly called.
In this case they are made out of cast iron and are non compressible. They merely spread the load on the concrete floor so that as the levelling screws are rotated they do not dig into the concrete at their small contact point.
I am now awaiting delivery of an engineers level to progress to the next stage
Ron
 
No worries Ron, I didn't know that the term hockey puck has been borrowed for other purposes. :)
Sounds like your are rolling. Keep your stick on the ice, Mike
 
I have now received a new 150mm Engineers Level and a Ground Precision Test Bar with a 4MT taper. Finally get to set up my lathe accurately.

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First I raised the inner 2 feet at the headstock so the lathe was sitting on only the 2 outer feet at the head stock and the 2 feet at the tail stock. Next I levelled the headstock end back to front across the ways

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Then lowered the tailstock feet until the lathe was level longitudinally using the level on the front flat way.

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Then levelled the tailstock across the ways. If both the headstock and tail stock ends are "perfectly level" then there should be no twist in the bed. Repeated this procedure several times as slight changes at the tailstock does effect the headstock level.
Finally the checked to see if the rear flat way was also level ( Double check on bed) and all was well.

Two things I did notice was that the threads in the 16mm Levelling bolts are quite coarse and very small degrees of adjustment alter the level appreciably. Also locking the nuts on the adjuster feet causes significant changes in level. Had to fiddle quite a bit to get the lathe level after the feet nuts were locked up. Took quite a long time and multiple tries.

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Now what to do about the inner two feet at the Headstock?
rbjscott ( Bob) suggested putting a test bar in the chuck and running an indicator along the top as you adjust the inner feet.

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Well I bought a ground test bar ( specified max 0.01mm runout) with a MT4 shank. Placed it in Headstock MT with a DTI indicator on top and rotated spindle. At the headstock the runout was barely measurable on my 0.01 DTI, probably around 0.002-0.003 mm. At the end of the bar (275mm, about 10", from spindle) the runout was bit more ( about 0.015mm) I rotated the spindle to set the runout to the midpoint and transversed the DTI along the bar and there was only about 0.01mm variation.

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Now to adjust the inner feet. If Bob was right then lowering the inner feet to take more weight should raise the far end of the test bar.
No luck. Raising the inner feet merely lifted the outer feet off their pads but made no change to the DTI reading on the test bar. The lathe bed is just too rigid under the head stock to bend no matter which pair of feet ( Inner or Outer) the lathe is resting on. In the end I just adjusted the inner feet to take what I felt was an even amount of the headstock weight ( No hockey puck could be moved with firm hand pressure and left it at that.

Next is machine a two collar test bar for a final alignment. I have a 40mm piece of Alu to use but no 25-50mm Micrometer so this will just have to wait.

The Ground PrecisionTest Bar has another use in that it is centred both end and placed between centres can be used to adjust the tailstock alignment.

In the meantime I have actually used my machine to size several plastic irrigation fittings. The machine is pleasantly quiet ( better than expected for a geared head machine) and very smooth. The QCGB and the D14 Camlock chuck are great improvements over my old Mini lathe. Happy Ron!!!!!!!!! :):):)
 
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