12' workbench material selection & const? (and newbie...)

[Mark Feffer]

Hi. I discovered this board last night, and have been exploring the threads now for at least 4 hours !!

I'd like to get some opinions and the benefit of all your collective experiences. I recently acquired a 12' x 16' prebuilt shed which I will use as a general purpose and woodworking workshop. There is a 36" standard door centered on one of the 12' ends. I'm considering building a workbench/countertop across the entire opposite end. The work surface dimensions will be 32" x 11' 5"

The quick/dirty way would be to just nail 12' 2x4s to the exposed studs on the sides and then screw plywood down to that.

However, I don't like a plywood benchtop because it tends to be soft and can flex. My latest idea for the bench top is to glue 2 pieces of 3/4" plywood (or 3/4" MDF or 1 of each) together, then edge band with some hardwood and then lay in 1/4" hardboard for the surface. I am centering an old metal tool drawer set underneath, so I can't put any supports dead center. But, I can support the top on the drawers' frame, which is 32.5" high. I don't want the finished surface higher than 36" because I am only 5' 8" and I also don't want it higher than my radial arm saw table, which is at 36". So I am limited to a top thickness of 3.5"

So, what are your opinions are in the areas of: 1. use MDF or not? (the shed is outdoors and I'm concerned with moisture absorption/swelling) 2. Use a torsion box? 2a. Minimum dimensions and material selection for internal stiffeners for torsion box? 3. Top surface materials? (i.e. melamine, hardboard, etc.) 4. Should I just build a freestanding bench instead? 5. Is it conceiveable/affordable to get a 12' piece of hardboard for the work surface? (For now, I am planning on having a seam.) 6. Will the top be ok just supported on the metal drawer frame, or should I add more support?

Here's a picture of the shed being delivered: PC182349 (Small).JPG

Thanks, Mark Feffer

[Don Bullock]

Welcome Mark. Congratulations on your new shed for a shop. I know you'll find this place to be amazing -- full of great people full of valuable information.

[Ned Bulken]

Mark,
welcome to the forums! I am planning a small shop, the same size as yours, slightly different style though, gambrel roof which will allow me to have a loft over one end for storage and whatnot. I'm probably the only person who won't tell you to 'build larger'.

1) MDF shouldn't be a problem, if you seal it on all sides.
2) torsion box would be plenty strong to support that. I've used them, my workbench had two halves, and the base was a torsion box.
3) If you go with masonite (hardboard) it will be easy to replace when you inevitably tear it up. I'd screw it down, instead of gluing, however.
4) freestanding allows flexibility in floorplan, which will be a good thing, given how you'll need to juggle tools/layout as you figure out what works or doesn't.
5) plan on a seam, yep. see above.
6) I'd support it more, even if only with 2x4 legs.

[glenn bradley]

I have a rolling worktable with a top as you describe. The hardboard wouldn't stay still as I had hoped but I wanted to be able to change it out once damaged. A few blobs of silicon rubber glue did the trick and the top can be pried up and the rubber cleans off easily enough.

[Mark Feffer]

Ned,

Thanks for the reply.

The MDF question is also related to hardness/stiffness. It's not a question of cost. SO, I guess the question isn't, "CAN I use MDF?" but rather, "SHOULD I use MDF?" I have never used MDF before, and I can get 3/4 inch plywood at HD or Lowes. I was just wondering if it would make for a stronger bench top, or one with less flex.

[Ned Bulken]

Mark,
I used a pair of pre-made bench tops which were laminated particle board atop hemlock risers with 1/2" plywood and pine torsion box plenty stout, they held Me up and I am Not what one can charitably call 'skinny'

A couple of MDF layers with a nice wooden edge would be good and stout, plus with the tempered masonite, you'd have a nice bench.

[Mark Feffer]

Great. Thanks for the advice. I am wiring the shop for 220v, so as soon as that's done, I'm going to make the bench.

Is there anything special to seal the MDF edges with, or will regular polyurethane do the trick?

[Mark Feffer]

Great. Thanks for the advice. I am wiring the shop for 220v, so as soon as that's done, I'm going to make the bench.

Is there anything special to seal the MDF edges with, or will regular polyurethane do the trick?

I just have to wait for the ground to thaw out enough to dig the trench for the wiring conduit.

[Ned Bulken]

I'd say poly would do nicely

[Scott Vigder]

I'd say poly would do nicely

I know Poly, and she does do nicely. I use her all the time.

I'm a big fan of torsion tables. A little extra effort up front and you have a rock-solid work surface for years to come.

The most recent tortion table I built is for assembly. If/when the surface becomes unusable I can simply flip it over and have a nice, shiny new surface to work on. I built my table a la David Marks' on his show. Search my previous threads for pics of the project if you are so inclined.

Welcome to the Creek, and what's with the sling on the arm?

[Mark Feffer]

Welcome to the Creek, and what's with the sling on the arm?

That's not my arm... ! (I was holding the camera.) Would anyone else care enough to take pictures of their shed being delivered???

The guy with the cast guy owns the shed moving business. BTW, the shed pickup and delivery was quite an operation, but that's for another post.

P.S. I will definitely look up the torsion box thread you mentioned. Since I am limited on top thickness, I'm not sure it will work for me. I don't know the minimum dimensions of the internal stiffeners to get the benefits.

[Mark Feffer]

Scott,

Thanks for the pics on the torsion box. I think I should rule that out due to the weight and also my limit on top thickness.

-Mark

[Scott Vigder]

Scott,

Thanks for the pics on the torsion box. I think I should rule that out due to the weight and also my limit on top thickness.

-Mark

I understand. It weighs as much as a Buick.

[lou sansone]

welcome to the creek

I would say that mdf with a laminate top would be a good way to go. I have made similar benches and they have held up. you just need to fully support it along its length to prevent sag over time.

best wishes
lou

[Peter Gavin]

I would just like to suggest maybe rethinking the whole fixed bench idea. 12' is probably more than enough and by fixing it in place you will probably end up using it more for a clutter than anything else. If you think you might ever get into using hand tools you will quickly realize that being able to move around a bench to attack the work from different angles is not only a back saver (not having to muscle the work around) but also a time saver. I have a six foot bench and it is centered in one end of my shop where I can get at the work a lot easier from any side. A six foot bench even against the wall would give you three feet of space on either end to work in. If necessary, build a cabinet under the bench and lose the mechanics toolbox. Once you realize how useful a real bench is (with a front vise and tail vise, dog holes etc.) you will appreciate how much of an actual tool it really is.

JMHO

Peter