# torsion box?



## stcroix123 (Oct 24, 2008)

i work outside in the backyard. the last couple of projects i've really felt the need for a truly flat surface to do glue ups and assembly on.it has to be light enough to store capable of being placedover sawhorses, &weatherproof. my idea is toget 2 by 3smaking acheckerboard frame 12" on center. 1 sheet of waterresitant 1/4 luan on bottom 3glued together on top. wrap in 1by 4 poplar ring the bottom with 1by 6 poplar for clamping surface. questions paint or spar varnish the unit? what glue between the 3 sheets ontop? being outside do i have to allow for ventilation? oh i do know 2by 3s aren't straight from the stores but can fix that. any thoughts?


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## smitty1967 (Feb 24, 2008)

my head hurts....


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## user4178 (Apr 18, 2008)

:laughing: Smitty, pass the aspiran please.


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## stcroix123 (Oct 24, 2008)

maybe i should have my daughter clean this up before i posted but she's at work. me no type to good. what must i explain better


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## user4178 (Apr 18, 2008)

I think I understand what it is you want, but, if you want something thats going to stay TRUELY FLAT, especially under the conditions you describe, I don't think makeing it from wood and seting it on sawhorses in your lawn is the solution.


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## smitty1967 (Feb 24, 2008)

Woodchuck: I got no aspirin, but my YL brought me home a brand new box of Bud Select bottles! you want one?

St. Croix: I gotta go with Woodchuck on this one....it almost seems like you're asking too much from the conditions and parameters you describe. I have seen outdoor- able (did I really just say that?) wood glue, and have used it on picnic tables before....seems to be holding up after 5 years in my back yard. But the other conditions like Woodchuck described--portable, outdoor, sawhorses--a wee bit too much to expect. Hell, I can barely get something truly flat on my new concrete floor!

Any other ideas that may substitute? I'd think it over before you went to the expense and time, only to be disappointed.

smitty


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## GeorgeC (Jul 30, 2008)

I think that you should look at your requirements somewhat differently.

Build a "box" that you can take outdoors and use. However, plan on keeping it stored inside out of the weather.

G


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## stcroix123 (Oct 24, 2008)

i'm running out of space in my shed. i want to store a torsion box under the eaves outside of the shed. i've also heard of it described as a stressed skin panel. the marx guy on the tv show woodworks made one out of mdf, which would be too heavy and not weatherproof enough for my usage. i was planning on using luan plywood because it's cheap and light, but it's only available in 1/4" around here, and i don't want to use spruce 2x3's, so i'm trying to think of a light alternative. i just need something better than a piece of plywood or a couple of boards because the lack of a good worksurface almost ruined my son's table. also, i haven't made many outdoor projects, so i'm wondering which is better - a good spar varnish or a good paint. and if you can come up with any other ideas i'd appreciate them as well.


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## smitty1967 (Feb 24, 2008)

stcroix123 said:


> if you can come up with any other ideas i'd appreciate them as well.


What about cyress? Exceptional weather durability, and generally lighter than other hardwoods. I used it once on a pation table set, and it is really user-friendly, machines well and behaves like pine or fir.

smitty


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## stcroix123 (Oct 24, 2008)

cypress is a good idea if a bit hard to find in area. will look though


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## mlightfoot (May 13, 2008)

I made the mdf one from the marks tv show and it works great but it is heavy. I set mine on sawhorses and shim it level. I need to get a neighbor to help me set it up when I need it. Mine is 4' x 7' and it took less than 8 hours to make excluding waiting for glue and finish to dry. I think your idea would work. However, you won't know how long it will stay perfectly straight untikl you try. To minimize the movement, I would use 1/2" plywood to make the interior frame. The plywood would be less prone to movement than the 1x3's. The only problem I see is laminating the 1/4 " luan plywood together. Maybe with contact cement? Spar varnish or something used on wooden boats would be a good finish. If you kept it covered with a tarp to keep the sun and most weather off of it, you may have something that lasts. It would be better than a sheet of plywood on sawhorses.


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## pianoman (Jan 16, 2008)

All right...here`s your answer...you need to pick a close grain wood. Say, Red Wood, Bass, Spruce, Catulpa or fir. Now build a Waffer pannel...yes a light weight,flat pannel using half lap joinery. Keep it about 3" squares. Rip the strips to 3/8th"s x 1 and 1/2"s 8 feet long. All half laps can be cut on the table saw using a dado set-up and a cross cut sled using the same method for making finger joined boxes...only 3"s apart. With the right sled you can cut 8 to 12 pieces per cut. Build the perimiter first with all the half lap groovs facing up...butt the corners...glue and pin. Next, cut the long strips for every 3" incrament...but the ends to the short sides...glue and pin. Now cut the short strips with half laps that fit into the long strips with opposite half laps. You can pin a 3/8" thick 4x8 ply sheet on top and bottom after gluing...fill all gaps on the edges with Bondo and Marine Varnish. The finnished pannel will be strong and flat! Rick


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## BudK (Mar 6, 2007)

It's not wood , but it might work . There is a pvc mat'l on the market in dimensional sizes . Sheets & whatnot . I used it to make sliding garage doors . The thread is around here somewhere . About as weather-proof as you can get . Good luck to you .
Bud


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## bradnailer (Nov 11, 2008)

stcroix123 said:


> i'm running out of space in my shed. .


The obvious solution is to build a bigger shed:laughing:


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## johnp (Nov 24, 2008)

why not just use a hollow core door.. instead of building one.. you could skin it with luan, if needed.. pretty simple to store.. most of us don't leave many tools out in the rain.. just a bad habit we have


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## Nate1778 (Mar 10, 2008)

This last copy of Fine Woodworking I got has just what your looking for. It is two torsion boxes, roughly ~80" long by ~15". They can be attache side by side for a large workbench, or length wise for long narrow glue ups. Also with it was a plan for some what appear to be sturdy sawhorses. Here is a link to the article.

Make Your Own Workbench with Project Plan


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