# It's been covered before but no definitive answer yet- Plywood or MDF workbench top ?



## Sirgreggins (Apr 12, 2012)

I'm looking into making a wall mounted folding workbench and i'm not sure what to use for it. MDF which is nice and flat but doesnt hold a screw well or plywood which can hold a screw, but might not be that flat. Either way i'm buying a 4'x8' sheet and cutting it into 4 layers which i'll laminate together for a nice thick top 48"x 24" The bench will have solid wood edging and a masonite skin. what do you think? i would like to use some bench dogs with a vise and i'll be doing mostly routing work, assembly work, some hand planing, and maybe some dovetails (which is why i'm doing 4 layers).


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## PurpLev (May 30, 2008)

If this was a finishing/assembly table - I would say MDF - cheap , flat , and replaceable.

If this is a construction/work table that will see banging (mallet), and need to hold material against hand planing forces (shear forces) and the likes -then I say plywood which can hold screws and be mounted more securely to the wall without it coming off during work.


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## Manitario (Jul 4, 2010)

no definitive answer because there isn't one…If you are using 4 layers and covering with masonite, I'd use whatever is cheapest.


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## RockyTopScott (Nov 16, 2008)

3 layers of ply, one MDF then the masonite top

Use contact cement for the masonite top


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## Sirgreggins (Apr 12, 2012)

Rocky, i think maybe i will do what you suggested just using one extra layer of ply. I probably wont glue the masonite down just so can replace it once it gets nasty. for the plywood, should i go with shop grade or homecenter hardwood veneer stuff?


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## RockyTopScott (Nov 16, 2008)

I would go to Home Depot and get the good Columbia Forest ply. You are only going to use half a sheet so you would have the other half for something else nice.

Goof idea not to glue the Masonite. When I do something similar I just put on an edge like 3/4 " poplar to keep the top from sliding around….maybe a few 23 gauge pins.


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## Sirgreggins (Apr 12, 2012)

thanks for the feedback Rocky. i really appreciate it!


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## Sirgreggins (Apr 12, 2012)

ive read in a number of places that gluing solid edging to plywood or mdf will cause it to warp and crack b/c it can'e expand others say it's not a problem. Thoughts?


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## RockyTopScott (Nov 16, 2008)

Good, not goof. Sorry


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## bondogaposis (Dec 18, 2011)

4 layers of MDF is going to be extremely heavy for a folding workbench.


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## Kazooman (Jan 20, 2013)

4 layers of MDF is going to be extremely heavy for a folding workbench.

I had the same thought. If this is to be 3/4 MDF then the bench will weigh about 80 pounds!


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## Sirgreggins (Apr 12, 2012)

in my garage we have storage rack bolted to the concrete floor and studs. I know 4 layers of ply and 1 of mdf is heavy but not too heavy i dont think. if you think about it 4 layers of ply is no heavier really than the 4'x 8; sheet, its just thicker b/c it's laminated. believe me this would be firmly bolted in place  If a wall can hold lumber rack than this bench shouldnt be too much to handle. There will be folding legs to support it. The design is based off this: http://lumberjocks.com/projects/67529


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## Smitty_Cabinetshop (Mar 26, 2011)

A wall that can't handle an 80 lb folding bench isn't a wall worth having…


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## Tennessee (Jul 8, 2011)

+1 for Rocky. Like the masonite top.


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## Bobmedic (Sep 24, 2010)

Torsion Box?


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## Dakkar (Feb 14, 2013)

I probably wont glue the masonite down just so can replace it once it gets nasty.

That's exactly the approach Norm Abram took with the first bench plan he built on New Yankee Workshop. He simply screwed a sheet of 1/8 masonite over plywood so he could replace the masonite when it got messed up.


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## Sirgreggins (Apr 12, 2012)

i was thinking about a torsion box but, since i cant really get a good setup for get everything perfectly level i went the lazy route with shear thickness. maybe i'll look into torsion again


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## wrightly (Mar 2, 2013)

i have a small table saw, i built tables around it and made a large surface, for cutting large sheets and i use it as a work surface too. is masonite and hardboard the same thing? i used plywood for the tables and covered them with hardboard, slick side up. i really like the combo. i think mdf underneath would have been just fine too. the hardboard, mdf combo would probably be cheaper, and you know the mdf should be flat.
i only have lowes, that's close to me. they store their plywood in a really bad way and it's almost impossible to find a flat piece. it drives me nuts


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## Holbs (Nov 4, 2012)

go torsion box like bob recommended. 
1.) cheaper (less material)
2.) lighter (less material)
3.) good experience
4.) you are a LumberJock

the setup is easy. do you not have 2 saw horses that can be shimmed to level? 2 winding sticks that can be made out of curtain rods? 3 or 4 planks of dimensioned lumber (if no planer/joiner there… can ask buddy or buy locally from cabinet shop)?
you can put oval holes in the stringers (i believe…someone say so if i'm wrong) as stringers are just to keep the top & bottom from collapsing upon itself, and even oval holes on the perimeter. this would take care of clamping and storage issues.
i've been reading up on torsion box design and mechanics. when i do mine, i will remember taller the stringers, stronger the torsion box. and i will cut ovals through just to minus off some of the weight.
again… you are a LumberJock. you gotta do the cool factor


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## PurpLev (May 30, 2008)

all great suggestions …
.
..
BUT

If this workbench is meant to be used for hand planing then you want it to be as heavy as possible - a torsion box will be too lightweight and your hand planing forces could potentially lift it and shift it around (yes I actually had a similar workbench myself)

For the same reason if you are planning on pounding on it with a mallet, then MDF would be a poor choice as the MDF (even with masonite to cover it) will get deformed and lose it's flatness if pounded on whereas plywood won't (as much).

going back to weight and it being supported with screws - with 4 layers and added weight, the wall supporting it wouldn't be so much the issues but the bolts/screws that secure it to the wall would - MDF wouldn't take the bolts as well as plywood when dealing with hand planing forces and folding it up and down forces applied to it on a regular basis.

just my $0.02


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## Sirgreggins (Apr 12, 2012)

what type of glue do you guys recommend for laminating these sheets? titebond III, cold press veneer, titebond I or II extend? just curious


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## roman (Sep 28, 2007)

I'm lost on whats the best top for a bench, so many choices, so many different opinions, so many glues, how thick, how big ? The answers are so many that its hard to imagine which is best ?

This I know for a fact. The top of the bench in all its practicality and common sense matters little. What is built and leaves the bench top is what really matters

Cheers


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## Sirgreggins (Apr 12, 2012)

Not to sounds like a jerk and its a good point, but do you have an opinion on the type of glue to use? I know now that i'll be laminating 4 layers of 3/4" plywood, 1 of 3/4" mdf, and topped with 1/4" hardboard and edging it with a hardwood so i can install a vise and use bench dogs. I'm sure the glue doesn't really matter too much but i'm curious if i should a glue specifically for veneer laminating or just a titebond extend glue.


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## crank49 (Apr 7, 2010)

I built my workbench, 25" x 84" with 4 layers of that South American Plywood they sell at HD. They some times call it *cabinet ply*, sometimes they call it *sand ply*. What ever; it has 7 plys and the outside plys are just as thick as the inner plys and there are almost no voids in it. As a bonus it is made with waterproof glue. It cost around $27 a sheet couple of years ago; the last time I bought any. I like this material and it made a great workbench top.

It is not 3/4" thick, however. It is somewhere close to 23/32" thick. My top is 4 layers of this stuff, 1 layer of 3/8 MDF, all glued and screwed together, then a replacable sheet of masonite held on with carpet tape. the big sandwich is banded with a maple 1×4. I made a 3/4" hole through the bottom layers near one end so I could use a dowel to push the top up to replace it.

I used Titebond III wood glue to build the top and left a big mortise for each leg in 3 layers of the plywood. I set the legs into the mortices with epoxy. The legs and all the strechers are built up of layers of plywood also. The legs are faced with 1×4 red oak.

I love this bench and the only thing I can think of I would do differently if I build another is I would remove the screws after the glue set overnight when I was building the top. I have screws on 8" centers all throughout the top. There are none visible from the top because I put this together upside down. The screws are only visible from the bottom. But now, If I want to drill a hole through the top to install something, I have to carefully calculate where the screws are so I don't run into one. And, after the glue dried, there was no good reason to leave the screws in there.


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## roman (Sep 28, 2007)

Like I said, the combinations and permutations that can go into a bench top, matter little to me : )

If your asking me what glue to use, then any glue will work, The failure of the glue joint on a laminated workbench top will have little consequence as with all that weight on the base that supports it, will surely test joinery skills ?


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## Sirgreggins (Apr 12, 2012)

thanks for all the feedback guys. This is why i come to LJ.


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## Bieser (Oct 30, 2012)

I agree with Bobmedic look into the Torsion box. I have built three of them and they are great and not hard to do. This would allow you to have it super flat and save some weight. I am about to build another one in the next month to do something similar to what you are thinking


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## rexb (Mar 28, 2012)

It sounds like you've got a solid plan, and I don't see any reason it wouldn't work. If you do decide to switch to a torsion box, here is what I did to beef up my bench top and get make it torsion box-esque.


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## Sirgreggins (Apr 12, 2012)

Thank Rex, i appreciate it. i'm going home this weekend and i will upload a picture of where i'd like to mount it, just b/c


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