Flat bench top on the cheap?

Jeff Horton

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I have my jointers bench wihich is solid wood, hand planed flat. I have a second all purpose bench that I do all manner of things on. I never intended for it to be very flat but now I find I keep wishing it was.

I have been thinking of building another solid wood top, adding dog holes, vices etc. that is not what I really need. So I am looking for a cheap and fast idea. What I need is flat surface to work off of. Do assembly, glue ups ect. I will cover it with a sheet of tempered Masonite and wax it so the glue doesn't stick. I don't want to build a torsion box, again I am looking for something quick.

I have toyed with the idea of putting a hollow core door down and then attach a sheet of MDF on that. But I have never worked with MDF enough to know if that would stay flat? My existing top is 8' by 3'. Assuming a 2'6 x 6'8" door there is not a lot hanging off unsupported.

Open to any other cheap ideas too.
 
My workbench top is 4 layers of MDF well supported and it has stayed flat. I built it with the option of adding a replaceable layer of 1/4" hardboard but have not found the need to add it so far. MDF treated with BLO and then paste wax bears quite a beating. Glue pops right off the wax as well.

My "all around" work surface does have a replaceable hardboard top but I've beat the hoo-ha out of it for 3 years and it hardly shows a mark. Now, where I hit the oak trim with the skilsaw . .. yeah, that shows.

P.s. the surface you mount MDF to needs to be flat and well supported. The factory support frame on my router table let the MDF sag over an unsupported span of about 20". Never though it would happen. I guess what I mean is that if your surface is not decently flat before you attach, the MDF will eventually deform.
 
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Can't find a door that big Ken. It would do great if I could though. My bench top is 3' x 8'

Interesting Glen. I don't do much on the bench that would damage it except glue. So treated MDF is probably fine. Just need a simple way to support it and keep it flat. Thats the main goal here.
 
I don't want to build a torsion box, again I am looking for something quick......I have toyed with the idea of putting a hollow core door down and then attach a sheet of MDF on that.
Hmmmmm.......

Well, as we all know, a hollow core door is a torsion box. I wonder, if you laminated two hollow core doors together and then topped it with MDF :huh:.
You'd have a bench top that is nearly 4" thick and should resist sagging and twisting pretty well. And best of all, cheap and fast.

Like I always say, Cheap - Fast - Good. Pick two.:rofl:
 
Can't find a door that big Ken. It would do great if I could though. My bench top is 3' x 8'

Interesting Glen. I don't do much on the bench that would damage it except glue. So treated MDF is probably fine. Just need a simple way to support it and keep it flat. Thats the main goal here.

Mine is here but I see you've posted on that thread. Anyway, I have 1 1/2" x 3" supports front to back 'about' every 14" over a 5 foot span plus front and rear rails side to side.
 
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A good frame and a piece of 3/4 MDF is my utility bench. You can beat the Poo out of it and it still is flat and nice. I trimmed the leading edges with some Oak strips Biscuited to keep it straight. Double thickness along the edges (same as kitchen counter tops are constructed. Holds bench dogs well, (secret is to let the holes soak up some sanding sealer to stablize the edges of the cutting.) That is where MDF fails is when it absorbs moisture and the edges fray then it starts splitting apart at the edges. Good sealing will eliminate that fault.
 
Marty,

The description of that bench is pretty amusing: "Original condition with puke green paint" ;) Yikes! ;)

If someone figures out a cheap, fast, *and* good way to a flat bench top, be sure to let me know... ;)

Thanks,

Bill
 
I would love to have that bench top, but
1. $300 isn't cheap at my house.
2. I have no use for puke green gym lockers. :)

I bought a maple(?) bench top a couple of weeks from the local salvage place a couple of weeks ago for an island in our kitchen. A little scarred but it will clean right up. They are in an old factory building and suspect it was part of the factory years ago. Anyway it's to small for my bench and my wife would beat me with some walnut scrap if I did.

I agree the MDF would do fine for what I want. I have a proper bench so dog holes are not even a consideration on this one. What I want to know is how you keep it flat? What kind of frame? Spacings, sizes, details!!
 
I would love to have that bench top, but
1. $300 isn't cheap at my house.
2. I have no use for puke green gym lockers. :)

I bought a maple(?) bench top a couple of weeks from the local salvage place a couple of weeks ago for an island in our kitchen. A little scarred but it will clean right up. They are in an old factory building and suspect it was part of the factory years ago. Anyway it's to small for my bench and my wife would beat me with some walnut scrap if I did.

I agree the MDF would do fine for what I want. I have a proper bench so dog holes are not even a consideration on this one. What I want to know is how you keep it flat? What kind of frame? Spacings, sizes, details!!

If we're talking one thickness of 3/4", I don't leave more than about 12" any direction unsupported. DAMHIKT. If you have some 2-by material laying around I would machine them down so they're true. For a 3' x 8' top I would build a frame around the outer edge leaving no overhang. Divide it down the middle lengthwise and have ribs about every foot front to back.

For this type of assembly, pocket holes work great on the ribs if they are not supported from underneath. If the ribs will be setting on your current top and can be shimmed, I would think gluing and brad nailing them (toe-nailed) would be OK.
 
Jeff

Why don't you build a torsion box? Half inch web 3/4 sides & ends & 1/2 inch skin or it you really want over kill 3/4" skins. Nice & flat & will stay that way. Top it with tempered Masonite & edge it with your favorite wood.

You could even inset extra blocking as you build it to mount vises to. You may even fill the voids where you may want dog holes later or along the front edge in for a ways to make it hard surface.

I don't like running full length pieces with little pieces between them. I prefer making my grid of notched interlocking pieces.

I think I would make the top skin something like Apple ply & cover it with Masonite.

This may not be cheap or fast but it is flat & enduring.
 

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Jeff I'd go with Bart's suggestion. I built a torsion box for my assembly table and topped it with 3\4" mdf. It has taken a beating but still going strong.
 
I don't want to build a torsion box, again I am looking for something quick.

Isn't a torsion box a pretty simple and quick solution? I would think that an easy half day's work would do it. 2-3 hrs on a Saturday afternoon, for instance.

Heck, you can even watch Marc build one on his website and pick up some ideas.
(I don't know that I'd be as picky as he is, but he sure ended up with a flat top, I'll wager.)
 
Art nailed it but I have to admit I have not looked at what would be involved in making a torsion box. Just assumed it would be a bigger project than half a day. If that is all, then it might be the better way.

My biggest problem is height..... BRB

Jeff looks for some shoes and heads down the stairs to the Lab. Gotta love a basement shop! .........<theme from Jeopardy plays in the background>..........

OK back. I don't want to go any higher than 4 3/4" for the top. 4" frame and 3/4 top. I made my base a bit taller than I meant to. Not sure what happened but it worked out OK. My bench height is fine as is, but I don't want it any higher than it is. I see a couple of options looking at it, but I guess I need to look closer a torsion box. It might be the better option since (I assume) it would stay flat for years down the road.

BTW, a friend of mine told me the best assembly table you will ever have was an old commercial sized glass door. He built a frame to support it. It was thick glass, weighted at least a couple of hundred pounds and he used it for years before he gave it to his brother. Pounded on it (not directly on the glass) did glue ups, stained, painted, whatever, you just scraped it off. He said you couldn't hurt it. Sounds scary but I believe him and it had to be flat!
 
Jeff,
My main bench has two layers of 3/4" MDF. The base consists of a WWII vintage metal office desk. Certified two hernia potential per lift. Once leveled, flat as could be! Just imaging 240 lbs on top of a 150lb lathe bed and headstock all rolling around on the top of the bench. No movement or flex from the top. I know three mile island can have a total core breach and this thing might glow, but still hold the top flat.

FWIW

Wes
 
jeff, if you decide to build a torsion box i`d advise against the use of mdf for the core...baltic at 3/4" would be my first choice and either a good grade of birch ply or even cdx for a second choice. southern yellow pine third choice.
 
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