18 – Torsion Box Assembly Table Top

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When assembling projects, nothing beats a wide and spacious dead flat surface. And one of the easiest and most efficient ways to create a dead flat surface is by constructing what is known as a torsion box. A torsion box is really nothing more than a grid-work with a skin on both sides. This creates a very strong, yet light, structure that resists warping and sagging. Its very similar to the concept behind an airplane wing. This episode covers the construction of the Torsion Box top and Episode 19 covers the construction of the base.

Build Along!

If you plan on building this project, this exploded diagram will give you the measurements you need to get the job done. A Sketchup file of this project is also available, thanks to Chris Williams.

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Categories: Projects, The Shop


  1. As always, awesome podcast!!! That assembly table looks to good to get dirty. Maybe it could be a rustic dinner table!!!

  2. Randy Klein June 3, 2007


    I’ve always heard that interior doors are torsion box design with cardboard innards and about an 1/8th” skin on both sides.

    Do you think its possible to simply throw on the 1/2″ MDF (that is what you used for skins, right) on both sides of an interior door (or 2 interior doors ganged up) as a way to accelerate the assembly table build-up?


    Thanks Andy.

    Randy: I know many folks who have used doors for workbenches and assembly tables with great success. The issue here is whether or not the doors are dead flat. Most likely, they are not. But are they flat enough for most things? Perhaps. Do you have a really high quality and very long straight edge? If so, check the doors and try to find the flattest ones possible. Joining two doors together and keeping the whole assembly flat could get tricky too. So is it a perfect substitution? No. Will it get the job done? Yuppers.

  4. Nicely done. Ironically, my torsion box assembly table needs to be redone right now and I’m inclined to scale down from 4 x 6 to 4 x 4 to conserve shop space.

    Did you find 4 x 4 was too small for many projects?

  5. Colby Hubler June 5, 2007

    Marc – great podcast! I have been needing to build one of these and have been putting it off – especially since I heard you were working on one for Fine Woodworking. Quick question with respect to the torsion box: The plans call for 3/4″ skins on the top and bottom, yet in the podcast you say they are 1/2″. Does it matter? What do you suggest? By the way, thanks for the drawer sizing tips on the base – great ideas!


    Hey Colby. I looked over the drawings and I dont see where it calls for 3/4″ skins. I did use 1/2″ material, but you certainly could use 3/4″ if you wanted to. The main difference is the whole table would be even heavier than it already is. Please let me know where the misprint is and I will try to have it corrected.

  7. UPDATE: We corrected the downloadable plan on Tuesday afternoon after discovering that it called for 3/4-in. skins rather than the correct 1/2 in. skins. This mistake also affected the width of the hardwood trim. The new plan is available on the site.

    Mark: Maybe you can print a quick note about this correction for the people who downloaded the plan before the correction was made. Sorry for the inconvenience.

    Matt Berger
    Fine Woodworking

  8. Paul (http://) June 6, 2007

    Another awesome installation Marc!

    But.. Marc.. oh Marc… how could you let your dear old step dad stand there sucking up all that MDF dust while you wore a full respirator?? Poor poor step dad.. :-)


    Paul Comi-

    I actually found the 4×6 to be fine for most projects. I went to 4×6 for two reason: because I could and because I usually have other crap on the table. I just needed more room to accomidate the crap and the projects. :) I think you will be satisfied with a 4×4 on most projects.

  10. Hi Marc,

    As a beginning amateur woodworker, I’m in deep-learn mode, and I feel so lucky to have found such a generous online teacher. You rock!

    I’m the guy with the incredible disappearing garage workshop :) All my tools stow in cabinets, and my workbench is my assembly table and it rolls into the corner at the end of the session. The laminated particle board top of my workbench was sagging in the middle. So I built your torsion box this weekend. Your excellent instructions and video gave me the confidence to try it! I shrunk the plan a bit to 24×48, 2 1/2″ inserts and 7 1/2″ internal box grid, 3/4″ MDF plus 1/4 hardboard top.

    I’ve got a few questions for you.

    1. I haven’t yet attached a bottom to the box – can I just use 1/4 hardboard to hold it all together, or do I really need the 1/2″ MDF for strength. Trying to slim it down a bit in weight and thickness!

    2. I don’t have all the tools I want yet- no brad nailer or hot glue, but I do have a nice freud 8″ dado set. So instead of cutting individual pieces inside the box, I made a 7.5″ box joint jig, and cut 1.25″ dados across full-length inserts so that it all fit together with just glue, no brads. Got the idea here.

    It worked pretty well, but I may have cut the dados a bit too tight, and while it worked ok in the dry fit- it was a bit tight during the glue-up, and i had some minor high spots. I planed as well as i could, but the final result was that the table turned out to be not quite dead flat. Could’ve also been less than perfect shimming, or the slightly bowed sheet of MDF didn’t want to settle, or just my inexperience. So my next question is, how flat is good enough? :) Using a long straightedge, it appears to drop about 1/32″ across the 24, and about 1/16″ across the 48 (or a bit more). I could conceivably pull out the screws and try your router-sled approach to flatten up the MDF? Might be an interesting effort. Or do you think I’d just screw it up worse?

    3. I’m thinking of trying some more skill-building here and miter the corners of the 4 hardwood sides, rather than butt-joining them. I haven’t been too successful in previous attempts with perfect mitered corners. Hard to get the lengths just right, etc. Any advice?

    4. Do you have any suggestions for how to mount a vice to the side of this 4″ top? I have a little wilton that sat flush with my old 2″ top but this new beast is twice as thick!

    Thanks again for all your great help!


    Hey John.

    Glad you are enjoying the podcasts!

    1- I do feel its necessary to go with at least 1/2″ material. I suppose you could use something thinner but I cant imagine the long term results being too good. Not to mention, if you ever clamp something to the table, you could easily punch through it. That would be a shame. :)

    2- That level of error doesnt sound too bad. Its a good idea to memorize the tables flaws, so that you can decide where to place things on the table. For things like chairs, you want to make sure the legs are perfect, so make sure you find a nice flat area, and keep it in mind in the future. So what Im saying is that the table doesnt need to be perfectly dead flat in all areas. But you should get to know the table so that you can predict for yourself how much that error will effect your work. And no I dont think it would be worth all the effort to do the router sled method.

    3- This is generally not the best project to test your skills in this area. The primary reason is that you might not have perfect right angles at your corners. The assembly table really isnt defendant on perfect corners so they might be a little off. If they are, your miters will cause you much headache. So maybe practice them on another project and go for the butt joints on this one. Of course this is just my advice so obviously feel free to do the miters, but dont blame yourself if they dont come out perfect.

    4- The only way I know of to get a vice on there is to make the table thinner or get a bigger vice. :) No tricks that I know of to get a small vice on a thick table.

    Good luck!

    • Curtis Reule December 21, 2009

      I finally got around to building a torsion box. Marc, I really liked your method and planned on following all aspects except I wanted to used dadoes. It was an extremely poor decision my part. Although everything went together with a nice tight fight :) the dadoes caused bowing and I ended up with much the same problem as Jon. I got out my trusty engineering hammer busted it apart and used your method which went together in way less time and was flat. If I ever do this again I will try to oversize the dadoes a bit.

  12. Tim June 15, 2007

    I have to point out a possible design flaw in your top. The whole point was to make the top hard board replaceable right? The oak sides sit flush to the hard board and so since you glued those on and doweled over the screw holes, how do you get the hard board out to replace it? Also as you mention in a previous post that you don’t know whether or not the table top is 90 degree or not. Trying to fit a piece in later could cause some headaches. Is this correct or how did you plan on dealing with that?

    I do like the hard board top though I work with that material all the time at work but never would have considered it for a work surface. After seeing that idea I think you could take it to the extreme and get yourself a 3/16 phenolic sheet (I don’t think you could 1/8 because it would be to brittle). It is much like hard board except like about 10 times more dense. The stuff I used to work with had a nice melamine finish on it as well. Would probably would never need to replace the top than.


    Hey Tim. The hardboard top will not be difficult to remove. Its just sitting on top of the table so the removal can be done by simply prying it up. Now when it comes time to drop the new top in, that shouldnt be too difficult. Although I didnt go through any great efforts to ensure that the table was perfectly square, it is definitely in the ballpark. So cutting a new piece shouldn’t be too challenging of a task. Aside from that, and I dont know why I didnt think of this in my other post, you have an exact-fitting sample already in your hands. The old top is a perfect template for the new one. So either figure out a way to flush trim it, or simply trace around the perimeter with a pencil and cut with a jig saw or circular saw. Piece of cake. :)
    Your phenolic idea is a good one. Although there is no surface in my shop that lasts forever. After several years of glue, stain, and finish abuse, that top is gonna look like poo. So as far as Im concerned, the top is always sacrificial. And the cheapest material wins.

    Take care.

  14. Tim June 15, 2007

    LOL! Yea didn’t think about using the old one as template!

  15. Mike June 18, 2007

    Hi Marc,

    First… Great Podcast.. I should say great podcasts, including Woodtalk online as well..

    So was wondering if using Resin impregnated honeycombs such as http://www.vacupress.com/accessories.htm#honeycomb

    Would these be suitable? Thinkin the 3/4″ and I’m asking this because yes I’m lazy!


    Hey Mike. I suppose that could work. At only 3/4″, you cant make a very big table though. Interesting product.


  17. Hi again Marc,

    I used #8 3/4″ brass wood screws to attach the hardboard to my 3/4″ MDF top.

    I’ve now learned just how bad MDF holds screws! In some places, the screw went in loose on the first try (won’t tighten to a stop- just starts turning in place). Bummer!

    Any suggestions?



    Hey John. I probably should have mentioned that in the video. As soon as the screws are below the surface, you should stop turning.

    The good thing is you really dont need much holding strength for the hardboard. Just something to hold it from flying away basically. :)

    So honestly, my suggestion would be to leave the stripped ones alone and just add a few more. When you replace the top, just yank those puppies out of there, fill the hole, and you will be good to go. But technically you could just throw the hardboard on and not worry about screws at all. I just like to screw mine down for extra security.


    • A good trick for fixing striped out screws is to drop in 1-2 toothpicks, cut so they are 1/8″ below the surface and then put your screw in. In other instances where you wont need to remove the screw, dab some glue in there and it will be rock solid for a very long time!

  19. Eric (http://) July 17, 2007

    I just built the box. As an alternate method to a block plane to remove high spots, I used a T-bar sander. This is a trick model aircraft builders use to even out all of the ribs on a wing before covering to get a uniform surface. I made a 24″ T-bar by butt-joining two pieces of MDF with glue. Then used spray contact cement to affix some 100 grit sandpaper to the flat surface. Sand the surface with this bar diagonally to the grid. The T bar spans 3 grid boxes or more taking out the high spots first and further flattening the surface.

  20. Mike Ward December 12, 2007

    Yo Marc!

    THis must be a very popular podcast, because I can’t download it. Got #19 just fine, but the needle in the record groove seems to have worn it out. (showing my age here). So, any chance you could repost this one? Thanks, Mike Ward

  21. Mike Kapotsy (http://) January 1, 2008


    My wife and I loved your assembly table podcast so much that we decided to build one for my garage. I am an avid woodworker and although my garage/shop is not as big as yours, the assembly table will help me in many ways including extra storage, table top workspace for projects, and organization. I have purchased the material to build it and will get started this week.

    I did want to ask you where you bought the switch you used for the compressor. I have not been able to find that style switch.

    Thanks, Mike Kapotsy

    P.S. I have ordered the urethane bandsaw tires. Thanks for the link!


    I got mine from Rockler. Looks as if they only make this slightly cooler one now:


    And you are very welcome. Thank YOU.

  23. Mike Kapotsy (http://) January 15, 2008

    I finally got the grid built and glued up this weekend. It was quite a challenge to get the thing dead flat level. I had to use two packs of shims and I still had a sligh sag on one side. Turns out one of my 2X4’s had a slight bow in it even though I ran it through my jointer. I made the mistake of thinking I could then rip it on the table saw and all would be good. Trouble was my jointer is a benchtop delta jointer with a very short bed on it. I wish I had a powermatic jointer like yours! Anyhow, I managed to use a couple of shims to correct the problem and get it pretty darn close. When I wrapped the mdf on the grid and screwed the hardboard on the top, the finished product was dead flat level! I did not have as easy of a time with the oak boards on the outside. I tried your clamping technique and unfortunately I did not have as much luck. I was lazy and didn’t use the brad nails to hold the boards in place and as I drove the screws the board pushed out a bit away from the MDF sides. It still looks nice and the tops are flush with the hardboard. I will send you some before and after pics of my shop once I am done. All I have left is to apply the poly on the base and the table, run my hoses and cords and screw the top in place!

    Mike K.

  24. Mike Kapotsy (http://) January 16, 2008


    I looked in my cabinet and all I have left over is some clear semi-gloss poly and no satin. The only other finishes I have available without buying some is a medium rubbed lacquer.

    Do you think the semi-gloss poly would be okay for this project?



    Semi gloss is fine. You aren’t really building up a big film anyway, so it really doesn’t matter. You basically want to give the material what it will absorb and then remove the excess.
    You could simply use wax, or even nothing at all. That poly was just a little extra detail that makes the top a little easier to clean.

  26. Mike Kapotsy (http://) January 17, 2008


    I bought 4 of the clamp it jigs from Rockler (used my own mini bessey clamps) and they worked great for framing up the torsion box. Thanks for that tip! Do you think the adjustable ones are worth the extra dough? Ever had a use for them?

    Mike K.


    Hey Mike. Haven’t used them and never really had a need yet.

  28. Joe June 6, 2008


    First, I love the show.

    I was trying to find a cut sheet to build the assembly table and have not been able to find one. Is there one and if so how can I get it?

    Also, now that you have used the table for a while is there anything you wish you could add to it to make it even more useful?

    I am also planning on putting wheels on the bottom. My shop is soooo much smaller than yours, and I don’t think I can put it in one spot without causing problems walking around the shop. If I place a 3/4 inch piece of plywood on the bottom and attach the wheels to that do you thing that would be sufficient to hold the assembly table in a “dead flat” position?

    I am going to be trying this plan this summer!!! Wish me luck.



    Hey Joe. Thanks for watching the show. There is no cut sheet. The measured drawing contains all of the measurements you will need to build the project.

    As far as adding things, I can honestly say no. Since this is version 2 of this table, this one has all the improvements I thought it needed from my experience with my first one. That’s not to say I wont think of something as time goes on. I just haven’t yet found anything to improve on.

    As for wheels, I just addressed this in the comments section of the episode on the table base. Check it out here: http://www.thewoodwhisperer.co.....ble-stand/

    Sounds like a great summer project man. And every piece you build after that will benefit from it. Good luck.

  30. Matt June 13, 2008


    I love your podcasts, particularly the two for this project. I’d love to build an assembly table right now, but I have an more urgent, alternative need for a torsion box and was hoping you could offer me some guidance.

    Rather than build a table which is supported by a cabinet base, I want to put up a shelf above my desk that is seven feet long and two feet deep and only supported along the walls on the back side and both ends but not the front. Obviously, I need the torsion box strength so that the shelf won’t sag. I thought a torsion box would be perfect for the application, but I imagine that the internal grid might have to be smaller than the 7 1/4 in. used for your assembly table. Any suggestion as to how to calculate the best size of the honeycombs for this application?


    PS: This shelf will be above my office desk, so to get some added usefulness out of this shelf and to make up for some of the space lost by the thickness of the torsion box, I plan to add some small drawers along the face, perhaps even a secret compartment or two. :)


    Hey Matt. I don’t really know of any true calculation for this. My advice would be get the lightest material possible, and make the shelf as thick as possible (while keeping the aesthetic you want). Those are the things that will affect the stability of the shelf. And if you are adding a few drawers, the inner grid will be at least a few inches thick which is probably fine for a shelf like that. Very cool idea Matt.

  32. Chris Rogers April 28, 2009

    Mark , a while back someone inquired if there was as easy formula for figuring out torsion box demensions. I don’t Know about easy but I’ve found that sticking with Torsion box demensions in multiples of 12″ seems to work out best,ie. 24″ by 60″. This allows for you to divide by multiples of 2″ for your inner structural board count ie. 60″/6″ =10 longer boards on 6″ centers,24″/6″=4*10(qnty long boards)= 40 shorter boards on 6″ centers.remmber to subtract stock thickness being used from both the longer and shorter boards. total thickness of torsion box should be in 2″ multiples as well (keep the math simple). Have you found this works for you. Chris

  33. MRod August 3, 2009

    Halo folks!!!

    Okay so with advice from Marc the WW and the just go and get it done folks at woodweb (http://www.woodweb.com/knowled.....ckets.html)

    I slung up a floating bookshelf last night that is – get this – 8 FEET LONG and 11″ deep, 1.75″ thick.

    All on a nice 8′ long cleat of oak and well see the pics for the rest.

    I threw 8 1 lb clamps and a sander on top of it. seems a bit wobbly but in sturdy. DOES THAT MAKE SENSE?

    I am banging on it and such and it seems sturdy, but I would think that if you grab any shelf hanging from toggle bolts (rated at 50 lbs) that it would wobble as a complete box…does that mean it is going to come flying out of the wall.

    I am using those more advanced toggle bolts that allow you to take them in and out until you commit to your spot. I have bolts every 18″.

    THIS IS A CUSTOMER PROJECT, therefore I will be uninstalling this soon and re-installing at the clients shop where they will put 30-40 1 lb coffee bag on it. It will be installed about 9′ from the ground into a 1/2″ drywall.

    HMMMM – your thoughts? Am I going to get a call back here?




      thewoodwhisperer August 3, 2009

      Hey MRod. I did see the image when I clicked on it.

      I think the shelf should hold 30-40 distributed pounds without trouble. And yes I agree that you will probably have a little wobble no matter what you do. Its just drywall after all.
      Now I am curious. You have a full 8′ span and no studs to anchor into??? What kind of wall is this?

  34. Murray September 19, 2009


    Thanks for the work you do in order to make all the good technical information, techniques, and projects available.

    I’m building a torsion box assembly table for my shop and wondered if OSB might be a good substitution for MDF, if not in place of the skins, at least in the place of the internal cross members. I’d like to have your thoughts?

    Also, up until now, I’ve used my 6′ x 6′ outfeed table for my table saw as my assembly table, but I’m considering making a smaller outfeed table and the same size assembly table which you have. If I make 2 separate tables, what size outfeed table would you consider adequate for handling plywood? And, how much lower would you make the outfeed table with reference to the height of the table saw?

    Thanks again,


      thewoodwhisperer September 19, 2009

      You are very welcome Murray. Thanks for watching.

      You can pretty much use any stable sheetgood for this project. The key is that the ribs are a uniform width and that they don’t move much with changes in moisture. With protective/sacrificial layer of hardboard on top, I think you would be fine with OSB throughout.

      That being said, most folks do go with MDF on this one and I have yet to hear from someone who used OSB. As you probably know OSB is not a “woodworker’s favorite” lol.

      As for the outfeed table, I would go about 1/8″ lower. And for dimensions, I like it to be as big as possible. Nothing like full support for a 4×8 sheet. But if you are looking for the minimal, I would say you want the width to at least match the width of the core part of the tablesaw table (not necessarily the extension beds). And for length, well, you can measure that based on an 8 foot length. You want to support a little more than half of the sheet AFTER the piece has passed beyond the blade. So just get a tape measure, head over to your saw, and measure out about 55-60″ or so from the back of the blade (more if you can). And that would be the amount of support you need for a piece to safely pass through the blade but still be supported enough not to topple over.

  35. Doug Barr November 11, 2009

    Marc, could you build a torsion box using an interlocking grid like you might use to separate sections of a drawer or small box? Do you think it might speed up assembly time? Would it be just as strong? Thanks Doug

      thewoodwhisperer November 11, 2009

      Hey Doug. A number of people have tried using alternative methods of creating the grid and all are valid. I think your idea would probably be even strong that just using butt joints and brads.

  36. Ron November 16, 2009

    Love your assembly table. One question – How did you attach your torsion box top to your cabinet?

      thewoodwhisperer November 16, 2009

      Just a few screws through the supports, up into the bottom of the torsion box. The thing is so heavy that you don’t need a whole lot of holding power.

  37. Michael Morton December 8, 2009

    Marc – I loved this idea and video when I first saw it and am just now finally getting a chance to build one! I’m posting some videos of my progress on The Wood Whisperer Community site. We’ll see how it all ends up!


  38. Michael Lehikoinen February 16, 2010

    Hi Marc,

    Great job on all of your podcasts. As a new woodworker with a small shop, I’m thinking of building one to double as an outfeed table but have 2 questions.

    1. Would putting a table such as this on lockable casters undermine the integrity of the torsion box?

    2. Did or can you use 1/2 inch plywood for the honeycomb frame?

    Keep up the awesome work!

      thewoodwhisperer February 16, 2010

      Hey Michael. I have heard of people putting the whole thing on casters, but I would imagine that could cause issues over time. When on casters, all the weight is being transferred to the 4 single points where the casters meet the ground. I imagine that puts a lot more stress on the torsion box than a base that’s resting directly on the ground. So I can’t say definitively, but I do believe it could cause issues over time.

      And yes, any sheetgood can be used for the honeycomb frame.

  39. Frank Kovach June 13, 2010

    I thought I would point out that you were ripping MDF on the table saw, wearing your respirator while your stepdad was helping to support and not wearing one. I’ll assume he is a champion free diver and was holding his breath. :)

      thewoodwhisperer June 13, 2010

      lol you’re late on that one. I think several folks already gave me crap about that. :)

  40. Matthias Inhoff October 12, 2010

    One thing I remember from my mechanical metrology days:
    If you have a flat table (like our surface plates out of granite), then you need a -point suspension/mounting. Therefore, mount the table or the entire assembly on 3 wheels, not 4. You’ll never get racking and the table will sta flat a lot longer. It mat not be perfectly level (unless you add levelling feet), but it will stay flat.
    I made mine 4 years ago out of mdf, 49″x61″ to suit my requirements. It’s more or less flat within +/- 0.002 all across, which suits me fine for what I do now. Wood moves, even mdf.
    Heck, in my past working life, I could measure the deflection of a 15″ thick solid granite surface plate of similar size when subjected to only a 20 lb load. However, that is not a requirement here and this project has worked great for me these past years.

  41. Matthias Inhoff October 12, 2010

    Second sentence should read “…need a 3-point suspension/mounting”.
    Please correct & thanks

  42. John October 29, 2010

    Your video inspired me to use a torsion box for a train layout.
    I made “torsion box” panel (1/8 inch plywood skins over a frame of 3/4 ply 3x44x88 with 2 cross bars 30 inches from each end) and want to make rather large openings in the skins. Any idea of how large of a hole I could make without weakening the panel enough to allow warping? I’d like to remove as much as of the bottom skin as possible to reduce weight. (Ask twice, cut once!) Thank you.


      Hey John. The truth is, I have no idea. I’m not much of an engineer and its hard to know at exactly what point the structure becomes prone to sagging. But my one comment would be about the 1/8″ skins. With such a thin skin, are you really losing all that much weight by removing material? I would suspect that the 3/4″ grid-work is the vast majority of your weight. Not sure the risk of losing structural integrity would be worth the small amount of weight loss.

  43. John October 29, 2010

    True enough, keep up the good work.

  44. Will November 5, 2010

    Like the build process/thinking. What about a formica top? It comes in pretty/hideous colors/patterns and repels most stuff I’ve seen short of meteorites. White is a great color for this to add passive lighting. Is there a concern about the contact cement being unlevel? You would basically have to kneel on it to do the job. Then trim, then add maple edge/rout. Oh and I would simply know where the screw holes were/write their locations on the bottom, and get rid of that section to get to the screws for removal, or you could screw from the top, I guess. Wax on screwheads if you didn’t. Thanks for this great site, glad I found it.



      Hey Will. Nothing wrong with a Formica top. But if I did go that route I would probably work it into the design so that its a more “permanent” situation. As you know, that stuff is pretty durable. One thing to keep in mind though is work-holding. Formica is pretty slippery stuff. So if you plan to clamp things to this bench, you’ll have to consider its lack of grip.

  45. Mike Maycott January 30, 2011

    Pulling top issue:

    To remove your replaceable top I would put a screw in and pull it up with pry-bar.


    Agree they would be concern. Agree current design would make a twist in base that might translate to top over time.

    Thank you for all the ideas.

  46. Mike Maycott February 8, 2011

    Why did you do a 50/50 on the top coat? Why not 100%?

    Is this for faster dry time?


  47. Mike February 8, 2011


  48. Dave Edwards February 19, 2011

    I have a smal cabinnet shop and I have used Formica on all work tops. It won’t be easy to get off but in 15 years it’s still in great shape. Now I must have a torsion box. Thanks for all the good info.

  49. dale rex February 21, 2011

    Jst got finished building the torsion box and base. Was alot of work but Im so very pleased with the results. Put on 3 coats of semi-gloss Arm-r-seal and the top looks great! Wrapped the edges with maple. On issue I’m having is that the top is a little slick from the semi-gloss Arm-r-seal.. I have a non slip router mat that I use alot, but its very small. Any suggestions to help the top be less slippery?

  50. Gareth March 4, 2011

    Marc, I’m gonna build one, I’m a beginner but I’m sure your excellent guide will help me.
    I note you have installed your compressor in the base cabinet and I too need a home for mine, how does this perform in respect to noise and vibration?


      Noise is significantly reduced and vibration just isn’t an issue. I highly recommend something like this. No more getting scared out of your wits when the compressor kicks in. :) I’d even go so far as lining the inside of the compressor compartment with carpet padding or something to further help deaden the sound.

  51. Ludovic March 16, 2011

    Hi Marc,

    I’ve followed both videos about the Torsion box.
    As it seems a good tool to assemble wood, I don’t have enought room to fit it in my workshop.

    I read on some french forums that the first project a new woodworker should be is the workbench: I’ve seen many workbenches, and I think it’s a good starting point.

    Do you agree with this, or do you think that the assembly table is more important than a good workbench ?
    Should I make a slightly bigger (more large) workbench instead of a workbench plus an assembly table ?



      Hi Ludovic. While I do think a workbench is a good project, I also think its one that is better off being made later in your career. The reason is because workbenches can be designed with all kinds of great features and options. But you don’t know what you are going to need just yet. So to get the most out of your workbench, I actually think its best to wait until you really know your needs as a woodworker. For instance, if you get more into hand tools as you progress, you are going to need a more versatile workbench. If you plan on using a lot of power tools, you won’t need nearly as complex of a setup.

      That said, you do need some sort of workbench. So I would say it might be a good idea to build a quick bench using a few layers of plywood for the top, wrapped in solid wood. Then attach a nice little quick release vise and make a stable base. But don’t go overboard. Use inexpensive materials so you don’t have a lot invested in it. You might wind up trashing it later or just recycling the parts. Then start building and start using the bench. After a year or two, you’ll have a much better idea of what you need for your bench, and where this temporary one falls short. Use that knowledge to build the bench that will be with your for life.

      As for the assembly table, I really consider it to be a separate tool. You can indeed build your bench wider or you can simply drop a piece of ply on top of you bench during assemblies. You don’t absolutely have to have both.

  52. Ian April 4, 2011


    Thanks for the excellent video! I’ve watched it several times now and plan to get started on my table this week. However, there is one thing that kills me every time I watch this video… Why did you start out by destroying that great table you had? Being the celebrity you are I’m sure you could have got a pretty penny for off eBay or maybe even given it to your father-in-law ;) It would have been nice to have around later in the video when you were putting the plywood on top of your saw. I’m just seeing things through the eyes of someone who is putting plywood on top of a saw regularly…

    Thanks again!


  53. Came across this yesterday. Great presentation. I get so tired of having doors come out twisted. I have been using a piece of ply between two sawhorses, nothing true or flat with them. This will give me something that I can count on as being flat so I can make sure my construction is true.
    Thanks again for a great video.


  54. Matthew May 10, 2011

    I’m building one of these workbenches for one of my small CNC routers. Thanks for the great video and Sketchup files. I’ll use my big CNC to cut some of the parts for me…..heck I might even build a big workbench and repurpose some of the 3030 and 1530 extruded aluminum 8020 into yet another CNC…

  55. David June 5, 2011

    This my be a dumb question, but that’s never stopped me before. Any reason not to build the base first and build the torsion box on top? With the leveled 2 x 4s to ensure flatness.

    Ghana as always.


  56. Beau June 29, 2011


    Learned this trick from a fellow much more experience and way smarter than I am. Who knows, he may have stolen it from someone else!

    After you shim the legs of the sawhorses as a level construction base, slop some of that putty or caulk you have laying around the shop over the sawhorse legs, shims and even the floor. It may prevent a clumsy footed builder from knocking the carefully inserted shims from flying across the shop floor and save the delicate ears of any innocent bystanders.

    Just don’t use anything you’ll have trouble scraping off the floor when that part of the project is finished.


  57. David July 4, 2011

    Well, I spent my July 4th weekend building the base cabinet (san drawers and doors) and most of the torsion box. I just don’t have the energy to try to flip that over.

    My biggest issue with the box (other than cutting the grid pieces to 7 1/8 instead of 7 1/4) was getting the brad nails in the pieces. You just “toed” in the nails. I found this almost impossible. Maybe my Porter Cable brad nailer is too big, but I couldn’t hold the piece straight when I pressed the nailer to get it to fire. And many times, because of the angle, the nail hit the cross piece and skewed off to the side. The pieces, then, werent 90*, but skewed out a bit. I couldn’t figure out how to get it right. But I was able to hold them straight when I nailed in the cross pieces. I ended up with an ugly grid, but the skin I put on seems flat.

    All in all, a good day in the shop.

    Happy 4th.

  58. Steve July 13, 2011

    Hi Marc,

    Love your series. You and Norm Abram rule.

    Question about your torsion box. Is there any reason one shouldn’t just half-joint a bunch of boards to form the internal structure rather than glue and nail the individual spacers?

    I’m very new to wood working so pardon my ignorance.



  59. Justin L August 11, 2011

    Hi Marc,

    I just wanted to say that I just built this torsion box table over the last couple weeks and it turned out great! I doubled this as an out-feed table for my table saw and had to make a few modifications. But overall, it is outstanding!


  60. Eamonn August 12, 2011


    Thanks for the assembly table design, it is just what I needed as I am about to start building a full set of kitchen cabinets (my first real wood project). I built the torsion box, and although I did have problems with toenailing the grid it came out perfect – dead flat everywhere to within .002″. However I might have made a mistake when I chose to use the waxed mdf support sheet as the top skin. I was thinking I would just use it “as is” and apply more wax, but now I want a more durable surface.

    The options I could think of are:
    a) plastic laminate, but I am not sure if the contact adhesive will stick to the “thoroughly” waxed mdf… and I don’t know how I could remove the wax.
    b) sand the surface a bit and the use poy/varnish mixture – again I don’t know if the wax will cause issues
    c) use a harboard top the way you did it. Problem here is I don’t know how to get the screws flush with the top. I experimented with some scrap and I can’t get a good accurate countersink in the harboard, not to mention screwing into MDF; using fine-thread drywall screws seems to be the best bet, but still not perfect. Also, the hardboard I have does not lay flat, I would need a lot of screws. Maybe the type of harboard I have is not the same as yours – mine is like pegboard material 1/8″ think. What did you use?

    Any suggestions on the best way to deal with the top skin will be most welcome; everything else is on hold until I finish it :)

    Thanks agian for a great article/video

  61. Geoff Smith October 20, 2011

    Brilliant video and great informative explanation …I am making one !….just one point, you need to get a dustmask for your step dad…you may need him for the next project ! LOL thanks again I am a fan from the UK. Geoff

  62. ngabriel May 7, 2012

    I started making my grid today. I got as far as starting my second row when I found that my brad nailer (which I bought just for this project) is simply too big to fit in the 7.25″ grid spaces. Oops! I then went back to the video and observed a funny thing. Notice the tool change that occurs just as second row is started (@13:35). You are one sly devil Marc.

  63. Jeremy A. July 31, 2012

    Great video. Just wanted to ask, is there any particular reason you couldn’t true up the new assembly table base and use that vs. the saw horses?

  64. BransonR August 26, 2012


    I am about to tackle this challenge of the table. Thanks for the great videos and putting this out there. I am just starting in the hobby and still figuring a lot out!

    My question concern is this….

    I understand using the saw horses, shims, etc… to get the table flat dead flat. My next concern is how to get the base dead flat. My garage floor is not level.. I was hoping to use heavy duty casters, but I wouldn’t be able to level the base. Is it is just important to get my base perfectly level? Or with the torsion box being dead flat all I need. Any help would be appreciated. I have also thought of using heavy duty leveling feet.



      I suppose if the base is not dead flat, it could pull the torsion box out of flat over time. But one thing you might do is get the base in position and either level it, or ship that gaps that exist between the torsion box and the top of the base. The problem here is that you want things to be mobile. If that’s the case, then there really isn’t a whole lot you can do. If the unit is in a different location periodically, you’re just going to have to roll with the punches and hope everything stays flat over time. How much actual impact you’ll see in the flatness of the top is something that I can’t even begin to predict. It might be an issue and it might not. But I would just make an effort to ensure there are no gaps between your base and the torsion box and you’ll probably be ok.

    • George July 3, 2013

      I’m thinking of using the leveling casters on my bench. Though it’s a bit expensive and might be fiddly if you need to move the bench often: https://www.google.com/search?q=coasters+levelers

  65. chuck September 19, 2013

    hi marc cant seem to watch video of torsion box top video do I needto be a member for that? great website

  66. Jim DeYoung January 7, 2014

    Very good video! I plan on building a torsion box top . I would like to know what gauge brad nailer you used while doing the torsion box. I am going to purchase a brad nailer but I can not figure which would be more useful the 16 gauge or the 18 gauge. What do you think?

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