Floor support for Lathe

[Mike Minto]

I guess I have to break down and add supports to my shop floor. Even with the additions to my 1624 (cast iron stand, 300 lbs sand), when I put on an uneven, rough green blank only about 10x10 inches (like I did this morning), the machine rocks back and forth so bad I can't put steel to wood. I'll be cutting and lifting the 3/4 treated plywood floor and putting in 2x8 bracing under the lathe's footprint this weekend, unless someone can think of another idea of how to stabilize this Tazmanian devil. I even screwed a 2x4 into one of the boards holding the ballast on the stand, and screwed that into a stud in my shop wall. Didn't do a thing to stabilize it. Thanks, Mike :mad:

[Steve Busey]

Mike, what's your floor over - basement? Crawl space? Is there any way to reinforce the floor from below with 4x4 posts or concrete blocks?

[Benjamin Dahl]

are there any leveling bolts on the feet? I had a similar problem due to an uneven floor (different lathe) and with a couple of turns on the bolts that resolved my problem. if there are no bolts, maybe a shim or two could help.
Ben

[Mike Minto]

The floor is in a 14x10 shed, which is my woodshop. I'm sure there is some sort of crawl space, but since the shed came with the house, I've never looked under the floor. I am still weighing wether or not wood supports will do the trick, but if it's not too much trouble, I still may put some sort of concrete footer in there. I tried using the leveling bolts that came with the cast iron stand, but that did nothing - I can see the wood floor flexing at a seam as a piece rotates out of balance on the lathe. I'll post pics. Mike

[Richard Madison]

One vote for concrete. Use 3/8 or 1/2" rebar, 12" on center, both directions, and tie wire all the intersections. Support the rebar on saddles so it is approximately centered within the slab.

[robert hainstock]

You need to take a look at the joists under the floor, they should be at least two X eight and supported by several posts. If you can jump on it in the middle and see or feel the "give" it probably doesn't have much support. You may get into a major reconstruction project. It seems obvious that some kind of shoring is needed. :eek::eek::eek:
Bob

[curtis rosche]

you could just drill 4 holes one for each leg, then put a pipe into the ground, put caps on top of the pipes, bolt the lathe to it,

[Bruce Pennell]

Mike before going to all the trouble of cutting the floor up. I would get two pieces of steel, heavy walled square steel 1X1 or 2X2 ( larger if you want your lathe higher). cut them long enough so you can screw them to your legs (drill one small hole for your bolt to attach to your legs, enlarge the other side so you can use a socket wrench to tighten the bolts) Than drill 3 or 4 holes and attach (lag bolt) to your floor joists. That should take the stress of the 3/4 inch ply and spread the force on to a few of the joist. Doesn't sound like a fun project, good luck I hope this helps....Bruce
You may be able to jack up your lathe, slide in the steel, drill and tap from the top of the feet into the steel. Save you the trouble of having to unload the lathe.
Mike make sure to run the steel across multiple joist to spread the load.

[Scott Conners]

I agree with Curtis, getting to the dirt (if you can) is going to be far more solid than anything sitting on suspended wood. Depending on the ground in your area you could just drive some pipe down into the dirt at four corners. Weld on a large nut to the top and you use can use combinations of allthread and nuts to make levelers. If you can't drive pipe into the ground you can dig a small hole and pour some concrete around a pipe with an elbow and nipple on it. If you work between joists you probably could do it with minimal demo and repair.

Second thought: how about driving/pouring some concrete around some 1" allthread and using it only to stabilize, leaving the lathe sitting on the wood floor? It wouldn't have to be nearly such a large construction as a full support, and if you brought it up just outside the four corners, it could be bolted to the stand to prevent vertical motion.

[curtis rosche]

by putting it into the ground, you dont have to worry about the vibrations from the lathe trying to loosen the nails and boards that make up the shed

[Mike Minto]

well, the latest is i got home from work last night, and was able to pull up the floor and look at what there was to work with. with earth looking back at me, and too much space to think about filling it up with cement (no more herculean effort coming out of me, i'm 50 now), i decided to shore the existing joist system. surprisingly, the floor joists were only 2x6's, which i sistered more 2x6's and 2x8's to. replacing the piece of 3/4 floor i had cut out for access, i used longer deck screws to secure it all back together. now, with the cast iron stand and sand on the new floor, i have a greater stability which let me rough turn an unbalanced, green blank of cherry. the lathe did not rock. i feel confident it will finally have the stability to hold anything i'm likely to put on it - now if i can just figure a way to keep that piece of maple i tried earlier in the week screwed to the faceplate - the screws keep coming out - a little punky inside, i guess. thanks for all the ideas, hope i don't need to do any more remodeling, mike :)

[Thomas Canfield]

Mike,

A member in our local turning club recently bought a Powermatic 3520B and set it up in a wood frame shop like you are describing. The plywood floor had noticible flex with just walking. I suggested that he lay a 2x12 across 3 floor joist minimum at each end and set his lathe on the 2x12s. It raises the lathe 1 1/2" but he reported that it dramatically stiffened the floor. He is just getting into turning so has not really put a "chunk" of unbalanced wood on the lathe yet. I do suspect that you will need to address the plywood floor and stiffen that as well as the joists. A "strong back" of 2x6 or so could be added to the 2x12 to fit just outside the lathe legs to add to rigidity of the 2x12 and that should be screwed to the plywood when everything is set.

I hope to make another visit and see what he has done, but the single layer plywood floor should be addressed for the lathe load.

[Mike Minto]

Thomas, great idea. I had originally placed 20" 1x4's under each set of legs, but with the flex in the floor, it really did not help. The 2x material would be better, I'm sure, particularly now that the floor is stronger from underneath. I'll see how it goes. The only other thing I'm noticing now is that the lathe is putting out some new vibration that emits an annoying sound. Not a factor in the turning, just not as quiet as it used to be. Mike :eek:

[Chris Stolicky]

As many have indicated above...

The wider your base the more stable the lathe will be. Adding something under the legs that crosses (transfers load) over a couple of beams will greatly stabilize things; rather than relying on 3/4" plywood. Even adding an additional sheet or two of 3/4" plywood under the lathe would make a big difference. Good luck.

[Bob Justin]

Mike,

Along with doubling up the joists, I would look at digging out some of the dirt and mixing a few bags of the pre-mixed concrete and put a galvanized post bracket in and then carrage bolt a post to your existing joist system at four points. Taking the load to ground is the best way to eliminate vibration and movement. Hardest part would be to wait a few days to let the concerte to cure some before putting a full load on the bracket. :)

[Dick Strauss]

Mike,
Just raising or lowering the speed of a piece by 20 rpms can often be enough to eliminate the vibration/shaking you describe. That is part of the beauty of a electronic variable speed lathe! Try tweaking the speed slightly when you have this issue and you'll be amazed how much of a difference it makes...!

[Mike Minto]

Mike,
Just raising or lowering the speed of a piece by 20 rpms can often be enough to eliminate the vibration/shaking you describe. That is part of the beauty of a electronic variable speed lathe! Try tweaking the speed slightly when you have this issue and you'll be amazed how much of a difference it makes...!

Dick, the 1624-44 is a manually changed, 8 speed step pulley design - no variable speed. Mike

[Mike Ramsey]

Mike,

A member in our local turning club recently bought a Powermatic 3520B and set it up in a wood frame shop like you are describing. The plywood floor had noticible flex with just walking. I suggested that he lay a 2x12 across 3 floor joist minimum at each end and set his lathe on the 2x12s. It raises the lathe 1 1/2" but he reported that it dramatically stiffened the floor. He is just getting into turning so has not really put a "chunk" of unbalanced wood on the lathe yet. I do suspect that you will need to address the plywood floor and stiffen that as well as the joists. A "strong back" of 2x6 or so could be added to the 2x12 to fit just outside the lathe legs to add to rigidity of the 2x12 and that should be screwed to the plywood when everything is set.

I hope to make another visit and see what he has done, but the single layer plywood floor should be addressed for the lathe load.


I have the exact same flooring/problem as Mike, I used 2x6s to help stabilize the floor (no 2x12s laying around) The pics dont show the
additional 2x6s I later put down under the feet (cross ways),This helped some but did not fix all the flexing, later I will pull up the plywood & add cross braces every where I can.

93067

93068

[Thomas Canfield]

Mike Ramsey,

The long 2x if crossing the floor joists should help spread the load. One suggestion to your lathe set up would be to raise the bed extension to the lathe height unless you plan to do some large turning often. That will allow you to position your motor and drive and more evenly distribute the weight and unbalanced forces, and also have more room to move the tailstock out of the way without removing it.

It would seem that a single layer plywood floor is just too much a flexible daphram for the weight of a large lathe. Some additional thickness and even support points for the floor joists would seem to be in order as you mentioned.

[Mike Ramsey]

For many reasons the bed extension position is right where I want it to be. I just need to do more under floor bracing. Also it's not an issue for me to move the head stock
down to the lower position.