# Lathe Bench - Laminated Mdf?



## sbx (Apr 18, 2015)

Hey all, 

So, I am having a hard time figuring out what I'd like to do for a benchtop for my Southbend 9A. Its has a 42" bed, and horizontal drive. I have a fairly sturdy steel frame for it (came with purchase) that I'd like to re-use, but the top that came with it isn't in good shape, and I'd like to improve on the rigidity. 

So, after searching and not finding any cost effective solutions for dimensions I'd like, I thought I may try to fabricate something. 

Has anyone attempted to laminate several layers of 3/4" MDF to come up with a hard, think, somewhat flat top? 

I was contemplating doing 2-3 layers of 3/4", capped off with formica or better yet some sort of phenolic laminate to cover and seal off the mdf from exposure.

Any thoughts, experiences or advice would be appreciated. I rent a shop right now, so this may not be a permanent solution, but I do want something serviceable and able to function well with my lathe.

Thx, 
sbx


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## Eddyde (Apr 18, 2015)

2 or 3 layers would probably work if well supported, as even thick MDF will sag if the span is too great. I recommend laminating top and bottom surfaces as MDF is greatly affected by humidity changes and can bow if only sealed on one side. The other potential problem is bolting to MDF as it will compress over time causing the bolts to loosen. Epoxying in full length bushings can help avoid that problem.
Another approach would be to use a ¾"-1" thick piece of phenolic, it might cost a bit more but much less labor.


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## francist (Apr 18, 2015)

Eddyde has hit the nail on the head, so to speak. MDF will give a nice smooth surface but won't contibute much to rigidity if that's what you're after. If you have access to someone with a planer (for wood), laminating 2x4's on the flat would make a more rigid top with easier opportunity for fasteners. The MDF does have the advantage of increasing weight though, the stuff is heavy.

-frank


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## ch2co (Apr 18, 2015)

I ran a series of 2 x 8's bolted to the top of the metal framework of my stands and then covered that with 3/4 MDF .
You could park a car on top of it, and yes it is flat.

Chuck the Grumpy One


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## brino (Apr 18, 2015)

Hey Grumpy Chuck,

That would be very sturdy.
Do you have any trouble with the MDF absorbing oil and swelling up?
Or did you seal it with something?

-brino


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## ch2co (Apr 18, 2015)

Actually I covered the whole thing with a sheet of 18 ga. galvanized steel before
setting, shimming and bolting down the lathe.

Grumps


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## RJSakowski (Apr 18, 2015)

I would be concerned about dimensional stability of wood products, particularly humidity.  I built several lathe benches and use 7" channel for the base on a steel frame.  I then covered the top with steel sheet, welded to the top.  we go through a lot of exercise to insure that the bed is level to the accuracy of a machinists level, literally a half thousandth/ft to avoid bed twist and the problems that come with it. With a small lathe, you can get away with it.  For a 42" lathe, probably not.  You may actually be better with a more flexible  bench and relay on the rigidity of the lathe bed itself rather than forcing it to follow the contortions of an unstable material.  Just my $.02, take it for what it's worth.


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## 4GSR (Apr 18, 2015)

My 9A x 42" bed SBL has been setting on a bench/cabinet I built when I was 15 years old nearly 40 years ago.  It was made from some left over 5/8" thick particle board underlayment flooring from the house dad built for the family.  The top has two layers of 5/8" thick particle board on it.  Looks like crap now but is in good structural shape for the 4 or 5 times it has been moved over the years.  Probably has close to 200 lbs of tooling stuffed up inside the cabinets in the base besides the weight of the lathe itself.


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## Andre (Apr 18, 2015)

If you laminate MDF, I wonder if an edge of angle iron sandwiched in might help with sagging.


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## hman (Apr 18, 2015)

I have a double layer of 3/4" MDF under my Grizzly 9x20 lathe.  The lathe has a drip pan and I gave the MDF a couple coats of shellac (about 4 coats on the very thirsty edges).  The MDF is atop a very sturdy 2x4 frame.  Seems to be holding up well so far.

As for bolt strength of the MDF ... I "just snugged" a 1/2" bolt, with largish washers a lock washer and nylock nut, at the headstock end of the bed.  The tailstock end has a similar arrangement, except that I only collapsed the lock washer about half way.  This holds the bed in place, without imposing twisting forces on the bed.

The attached photo shows the table just before I slid the lathe over from the one it was on when I bought it used.


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## sbx (Apr 18, 2015)

Thanks for the input everyone. I thought about it some more, and ended up going with 2 layers of decent quality 3/4" Baltic Birch laminated for the top (clamped up and drying right now). If I had gone with MDF I was planning on some sort of laminate to seal it, but after pricing it out and not having any local sources for anything I liked laminate wise, I thought the ply was the way to go in this case, without spending a fortune. I think it will be a little more dimensionally stable and pretty rigid.

The steel frame I have is pretty rigid already, and will be reinforcing it with additional angle iron bracing.


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## stupoty (Apr 19, 2015)

I used to have my 19x20 bench lathe on a double layer bench made from ply, that was as solid as my 2x6 topped bench's.

Stuart


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## spongerich (May 1, 2015)

Before I found an old lathe cabinet for my horizontal milling machine, I'd stopped at the local kitchen counter place and asked about getting a piece of stone countertop.  You should be able to get an offcut, leftover or blemished piece for well under $100.  Glue it to a piece of 3/4 MDF or plywood and you've got a stable flat base.   If you mark the mounting holes, you can probably get them to drill it for a couple bucks.


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## 4GSR (May 2, 2015)

Ideal bench would have a top made of 1-1/2 steel plate.  Optional on the stress relieving!


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## brav65 (May 2, 2015)

sbx said:


> Thanks for the input everyone. I thought about it some more, and ended up going with 2 layers of decent quality 3/4" Baltic Birch laminated for the top (clamped up and drying right now). If I had gone with MDF I was planning on some sort of laminate to seal it, but after pricing it out and not having any local sources for anything I liked laminate wise, I thought the ply was the way to go in this case, without spending a fortune. I think it will be a little more dimensionally stable and pretty rigid.
> 
> The steel frame I have is pretty rigid already, and will be reinforcing it with additional angle iron bracing.




I just built a top using the same material, but I painted the top with Rustoleum Hamme finish paint in silver.  4 coats with my sprayer on all 6 sides and it looks great.  I banded the edges with maple and routed the edges with a 1/4"  bullnose bit.  It now looks like a metal top and should be very stable.  I am going to use uni strut for the base and mount 2" rubber caster with two way brakes (locked swivel and wheel)


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## kingmt01 (May 20, 2015)

You can always do a concert table. Do a form on top of what ever legs you decide on. I'm planning on doing this in my kitchen. Not for the lathe of course.


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## Ed of all trades (Jun 8, 2015)

I am using a band board for my table top on my lathe table.  It is used to tie the end of wooden I beams together. It is very solid and is over 2" thick and has very little flex even in long lengths. It is also very stable due to the glues in it.  I lucked up and found some at a yard sale but building supply stores sell it by the foot and will cut to any length you need.


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