Lathe Leveling

[StudioMachinist]

Travelling back to the house tomorrow, looking forward to finishing my lathe stand and it just clicked how difficult it will be to level the lathe on the stand I created.

Some have already seen pics of my WIP stand but it's basically a steel and wood table supporting a 5' grout filled beam that the lathe can be bolted to. Just looking at the profile of the tube you can see there is nothing truly square - one side is convex, the other concave, I'm sure the penetrators added some warpage during welding and it rests on wood glued and bolted to wood glued and bolted to pipe flanges...

The only thing I can think of is welding ground flat plate on the headstock and tailstock ends where the lathe feet will rest using a 6' level very carefully.

Attached some pics so you can get an idea of what's going on. Keep in mind the beam is now filled with grout.

 

[sdelivery]

Don't sweat it so much. Get the bench level before adding the lathe.
Since you don't have production requirements let it sit. Come back later and rough level it.
Again let it sit. Finish level and make your two collar test.
Even big cast iron beds " bend and twist"
Some times I have to back the leveling screws and leave weight on the bed overnight.
As a hobbiest your not in a hurry so after your final level allow it time.
I really like this design and think it will relax and be incredibly rigid.

 

[tq60]

Coaxial scrrews...

Our SB 14.5 came with some 1/2 inch steel plate as footing, a square at headstock and rectangle at tailstock.

The edges beveled, looks nice.

We modified it some, original was lathe just placed on the plate, not bolted to plate, but adjustable feet...how?

The holes are already correct size to tap for 5/8 thread, have buckets of these left Over from shop build.

Thread lathe holes the fit bolts.

With lathe, drill 1/4 hole through center of 6 bolts and place in all holes, align all plates.

Drill plate with 1/4 holes using bolts as guides.

Remove plates and drill tap to 5/16

Drill bolts to same.

Replace plates, the 5/16 bolt is 3/8 longer than the 5/8 bolt so it does not go past the plate.

The 5/8 bolt supports the lathe above the steel plate to level the lathe, then smaller one secures it

You can do same, stud from bottom holds lathe via coaxial bolt to allow adjustment..

Sent from my SM-G781V using Tapatalk

 

[sdelivery]

Machines were set in place and steel wedges were used to level the machine and grout was used to fill the space, the holes were used to tie the machine to the floor.
Most machines were designed to use the floor as a second plane that created the rigidity that allowed heavy accurate cuts.
One possible solution is to use the plates like a jacking surface while using a toe clamp to clamp down.
But I wouldn't want to drill a hole in my concrete floor.....
So we have glued plates to the floor with epoxy a threaded stud is welded to the plate, using shims underneath and a hold down nut on top.
There are other ways to skin the cat but the principle is the same.

 

[mac1911]

I would level the table best as possible.
Place the lathe on the mounting area and see how it sits.
Any rocking? Any air gaps?

Since your mounting plate is not known to be flat , level or twisted you might need to bolt it down and run it and see how it works out.

I feel like that lathe already has more , un level , twist and slop built into it than your table will induce. Lol

Mount and make some stuff , then evaluate.

 

[Jake M]

I don't think there's much to worry about. How bad is the tube? I think if it were me (and not knowing the answer to that question), I think I'd lay the tube with the concave side down, use my level to pick through a handful of hardware grade washers, and select fit a washer (or two) such that I could lay the level in a levelish fashion across each pair of holes. if not perfectly level reading across each pair of holes. Seriously, standard "bright" stamped washers for grade 5 hardware, right out of a bulk bin. There's a remarkable variety of thicknesses in any given handful... If it needed more than that, shim stock is available in "washer shapes" too. Bolt it down as such, and see where it needs to go. Level is not relevant to cutting, level is ONLY an easily approachable datum for YOU, to allow you to more easily set the ways fairly close to parallel. Way more important if you had an industrial lathe with six, eight, ten or more pairs of levelers to get right. And you'd still have to tweak it depsnding on how it cuts. If it looks level, if tools don't roll off of the bench, it's level. Finer adjustments are done based on the machine it's self without regard to level anyhow.

You've got a ground up concept there that I really like, in keeping the lathe and the tube (beam?) rigid within themselves, and thereby removing a LOT of complications from the entire rest of the bench. I think the best answer to the leveling question is going to be to keep it within that concept by keeping it as simple as possible. Don't fall off of the wagon now... In other words, don't over think the problem or overbuild the solution. Shim the lathe on the tube as you had intended so that it's parallel, without regard to level. At that point you have something you could bolt on a pickup truck tailgate and start a mobile machining business anywhere you happened to park... Then level the table under it to whatever degree of level makes you happy.

 

[StudioMachinist]

Coaxial scrrews...

Our SB 14.5 came with some 1/2 inch steel plate as footing, a square at headstock and rectangle at tailstock.

The edges beveled, looks nice.

We modified it some, original was lathe just placed on the plate, not bolted to plate, but adjustable feet...how?

The holes are already correct size to tap for 5/8 thread, have buckets of these left Over from shop build.

Thread lathe holes the fit bolts.

With lathe, drill 1/4 hole through center of 6 bolts and place in all holes, align all plates.

Drill plate with 1/4 holes using bolts as guides.

Remove plates and drill tap to 5/16

Drill bolts to same.

Replace plates, the 5/16 bolt is 3/8 longer than the 5/8 bolt so it does not go past the plate.

The 5/8 bolt supports the lathe above the steel plate to level the lathe, then smaller one secures it

You can do same, stud from bottom holds lathe via coaxial bolt to allow adjustment..

Sent from my SM-G781V using Tapatalk

Woah, I think I need a visual aid.

 

[StudioMachinist]

I would level the table best as possible.
Place the lathe on the mounting area and see how it sits.
Any rocking? Any air gaps?

Since your mounting plate is not known to be flat , level or twisted you might need to bolt it down and run it and see how it works out.

I feel like that lathe already has more , un level , twist and slop built into it than your table will induce. Lol

Mount and make some stuff , then evaluate.

I'm going to take your advice and Jake M's down the road if I feel it necessary. Should have some pics of the finished machine setup today.