Lathe Mounting on Existing Bench

[rronald]

I got a shipping notice, but my bathroom scale won't be suitable for any answers. Doesn't matter much for handling.

I also bought a sheet of MDF yesterday and will be gluing up a torsion box for a new table top. Should keep the lathe flat. Here's a pic with the long pieces of the grid roughly in place. But it will make the bench top about 35" off the floor. Hopefully that will be a comfortable working height.

 

[rronald]

Torsion box glue up.

Only problem is moving it to the bench base. The top is somewhere between 150 and 200 lbs. The top and bottom skins are each a half sheet of 3/4" MDF, which is ~95 lbs. The grid is over 1/2 a sheet...with a few lbs of epoxy. I may be able to slide it to a cart...and then slide if off the cart onto the bench base. It's either that or go begging to my neighbor....who is a competitive body builder.

 

[Kronin]

Looking good!
I opted to weld a bench so I could learn another skill I'll be using going forward :-D
Gonna post a thread with my bench build once it's all done.
Just waiting on the lathe before I put in the mounting plates and paint/prime.
Can't wait to make first chips!

 

[rronald]

I like your leveling feet. My bench is decidedly not level. I'm pretty sure the table top will be flat, which should work regardless......but level would simplify measurement. I can either build a stand (much like yours), or add on some hardware (or wood shims) to level my bench top over the non-level bench, live with flat but un-level, or double my lathe costs by having my shed foundation leveled.

I don't like any of the alternatives. The easiest path is to just place the top over the bench and assume true is sufficient. Next easiest would be to shim the 6 front to back MDF supports with a 24" wedge that's about an inch wide (depth would start at zero and rise about 3/8 to 1/2" on the other end to restore "level". That should get me true and level...but if the bench or foundation moves, it might not be a permanent solution. I guess it's better to start out level.....so I suspect I'll do the wedges.

 

[matthewsx]

So, if you search lathe leveling here you’ll find out it’s about having the bed all in the same plane by removing any twist. Actually being level to the earth isn’t necessary. Lathes work on ships at sea, so there’s really no need to make sure the table is level as such.

John

 

[zippyslug31]

Your MDF torsion box looks like a great solution. I agree on using MDF for the top since it's pretty damn flat (for "wood", anyway) and I did something similar. I built my bench using 4x4's as the support and then made sure this structure was very close to perfectly flat by power planning the top. Once I had this dialed in, I just bedded down the MDF top using construction adhesive to eliminate any minor imperfections. Mine turned out great and it's as flat as wood is ever going to be.

You'll still need to work on leveling the lathe once it's put in place (to remove the twist) so you might want to reinforce your torsion box with solid wood where the mounting holes are located. Not doing so feels like you're going to be fighting with the slight give in the MDF when you're trying to cinch down on the mounting bolts when you try to correct the twist.

 

[rronald]

One more question. My bench top is 8 foot long. Lathe is under 5' long. I also have a foot or so to the right of the bench.

There's a note in the manual about leaving space to the tailstock side of the lathe for servicing the leadscrew. And I know that I want space on the headstock side to feed stock thru the head. How much space should I leave on the headstock side and how much space should I leave on the tailstock side?

 

[AllenV]

My $0.02 worth.
Lead screw "servicing" beyond oiling the bearings is pretty unusual. If you have enough space to get wrenches and oil cans at the bearing pillow block you're okay. Anything serious, such as removing the lead screw, can be accomplished by unbolting the lathe from the base and rotating it forward onto some other table you might bring in. From the picture on PM's website, 1 foot may be enough to to get the lead screw clear of the machine. Caveat, electronic lead screw conversions and the like may have different needs.

On the left side you need to get your body in there and mess with gears, belts, motors, switches. My body needs 3 feet. By the time any stock you have exceeds three feet it becomes unmanageable when rotating. Then again, if you have bench extending off to the left you could rig some sort of support scheme for long stock. I am sure gunsmiths have a different perspective. FYI, I put an 18-inch deep cabinet to the left of my lathe. And I park a MIG welder cart between the two. My spindle is more than 18" from the wall. Thus I actually have quite a lot of room for long stock to stick out. I just have not found it to be required.

 

[rronald]

Thanks for the quick response.

It sounds like it's not hyper-critical. I do have a big vice that I'd like to put on one end or the other. Probably better down on the tailstock end, since I won't be squeezing my body in there very often (if at all). I think I an do that while keeping almost 3' on the headstock side free.

 

[rronald]

Here's a picture of the new bench top in place. The other pics show the setup to lift the lathe to bench height and another structure built on the bench to allow lifting the lathe a couple of inches over the bench top for final positioning.