[How do I?] Help With Building A Stand For Lathe

[craftedmagazine]

Hey guys, hoping one of you might be able to help me out with this. I'm receiving a PM-1022V lathe today and need to build a stand for it. The lathe weighs around 370 lbs and is 42" long in total. I've drawn up an idea for a stand in SketchUp, screenshot below.



The stand is based on these plans: http://www.popularwoodworking.com/projects/ultimate-lathe-stand

I realize the lathe featured in the article is nowhere near the weight of my metal lathe, but I'm thinking that laminated plywood with knockdown joints should be seriously strong. Any thoughts? My scaled-up design will use close to three sheets of ¾" plywood, so it will be plenty heavy. I am not a welder (yet) or else I'd built it out of metal. Thoughts?

 

[intjonmiller]

Three sheets of 3/4" plywood will be substantial, assuming it's decent stuff (not like the crap from Home Depot that has delaminated on me in the past). But why knockdown joints? Does it need to fit through man doors or stairways? If not then I would avoid the knockdown fasteners and use glue on every inch of every mating surface. Biscuits or dowels or (especially) Dominos wouldn't be a bad idea either. Or the knockdown fasteners in place of those things, if you are set up to use those efficiently (CNC software, for instance, makes those a breeze) along with the glue so it won't actually be knocked-down at any point.

A wood lathe pushed to its max for large turnings is going to see a bigger weight impact from the workpiece than a metal lathe of similar scale for most projects. It's very rare to use a metal lathe at full diameter and length, whereas wood turners so often find a reason to do so (and to add risers to their head- and tailstocks to cheat it further). You're getting a bench lathe and that is a substantial bench design. I just wonder about the knockdown fasteners instead of permanent joints. It may be sufficient with them but if you don't need to disassemble it for any reason then don't include that weakness.

 

[Glenn Brooks]

Should be plenty strong. Second the glue and screw idea - elmers woodworking glue is cheap. Works great. The vertical pieces in the front might reduce your available space for storage. You could loose those lower pieces with no adverse affects - or replace them with 1 x 2 stringers. Even reduce the extra layer of ply ( just use one layer for the shells, two layers for the top. 3/4 ply is plenty strong, particularly if you put a stringer mid way.

Also it would look nice with a bit of trim around the edges - cover and seal the end grain also.

I varnished my birch plywood counter top to resist machine oil penetration and make it easier to sweep up chips.

 

[Glenn Brooks]

Forgot to mention - you might consider adding some angle brackets to the bottom and lag screwing the table to the floor for added rigidity. One thing about ply wood - the build will be a bit on the light side, compared to a metal table. so might transmit oscillation of the lathe to the floor more easily, and might 'walk around' on you. Also you can shim under the brackets to level the table if needed.

Glenn

 

[intjonmiller]

By the way, welcome!

I agree that the triple layer is probably overkill. I like the vertical aprons for rigidity (I just made some shelves that span a window the other day, using plywood in the same manner so it wouldn't sag across the span where no other supports were available), but you could reduce the size by making each shelf an independent torsion box instead. Make the long members continuous and the short members interrupted, forming webbing the full length, width, and height as the panels, with a sheet of plywood on the top and bottom. Glue every mating surface. And you could easily use 1/2" plywood for those and it would still be very strong.

 

[intjonmiller]

I disagree about the vibration factor. I find that vibrations are dampened by plywood (at least of this grade and quantity). It will be lighter than a cast iron base, but I doubt it will be any lighter than a folded sheet metal base, with far less concern of resonance. I have not used a plywood base for a bench lathe, but I have used it for countless other projects, both personal and professional. 3/4" plywood is over 60 pounds per sheet. I would be very surprised if it gives you any such trouble.

Also by using plywood rather than solid lumber you won't have any dimensional stability issues which could otherwise cause a slight warp in your lathe bed. I think it's an excellent choice of materials for this purpose.

 

[intjonmiller]

Oh, and congratulations on your purchase! I've eyed that one myself, though when I eventually upgrade from my mid-century 10" Logan lathe I will likely get something bigger. But I am very envious of many of the features of your machine. As mine was originally a turret lathe it did not include a quick change gear box, and the change gears are a real pain. Add in variable speed, built-in chip guard, and a steady rest, and you have a great setup that should serve you very well. Don't agonize over the bench/stand build. Just get it done and start turning metal!

 

[Tozguy]

I see no problem with over building it. Peace of mind is good. The PM1022 might not be the last lathe that goes on it.
Adjustable feet is a good idea since the stand should be very rigid and the weight distributed evenly on the floor.

 

[intjonmiller]

Excellent point! I should have taken photos of the process I used for making adjustable feet for the last plywood constructed machine stand I made. That was for a radial arm saw that needed to be not only stable, but perfectly in-line with the miter saw station immediately next to it. Their fences are inline and tables coplanar, so adjustable feet were critical.

I used 3/8" bolts, of which I have a tremendous number due to a bulk purchase from a closeout place for next to nothing a couple years ago. I have bolts of different lengths, regular and jam nuts, couplers, bushings, etc., all in 3/8"-16, so the choice of hardware was obvious for me. Fortunately the couplers are 9/16" at their narrowest point (designed for that size wrench), which is a nice fit within 3/4" plywood. I drilled a 1/2" hole with a forstner bit into the plywood, then used a simple jig with a 1/2"-3/8" bushing, a bolt, and a coupler to align the coupler with the hole, traced the shape of the coupler with a marking knife, then chiseled out the hexagonal shape very quickly. Couldn't be much easier.

I used four 3/4" plywood pucks, about 3" in diameter, with 3/4" diameter depressions drilled into the center, 1/4" deep, to receive the head of the bolt that I put in each adjustable foot assembly. That conforms slightly to the irregular surface of my shop floor, distributes the load from the cabinet/stand, and leaves just enough of the head of the bolt exposed to fit a wrench for adjustments. When the level is set a nut (spun on before assembly) is tightened against the coupler above, which is held stationary in its plywood home. It took about an hour to do all the cutting, drilling, chiseling, and assembly, and no more than 10 minutes to level it.

 

[craftedmagazine]

Thanks for all of the helpful replies, guys! I was just planning on the knockdown joints because that's what the original plan called for and I figured that might be stronger. This lathe is going in my garage shop so I have plenty of space to move materials around. I do plan on trimming at least the top with some hardwood pieces, which will improve the look as well as the longevity. I will probably finish the top with some Minwax Spar Urethane to help with wear.

Also, thanks for the welcome! Can't wait to get my feet wet in metalwork. I'm also planning to start making tobacco pipes as a hobby and most of those guys are using these types of lathes. I'll keep everyone posted!

P.S. any good resources you could point me to on learning how to run and maintain a lathe like this? I've definitely read up a bunch and watched a bunch on YouTube but I'm sure there's some good stuff out there I'm missing.