Maple workbench top rigidity question?

[Owen E Wheeler]

First post. Take it easy on me, I'm new here.

I've pulled the trigger on a Noden bench system, and ordered the 1 3/4" maple top they offer in 72 x 24. On the advice of Noden I went for the double cross member bracing instead of the single, as my #1 priority with this bench is rigidity while planing, etc. Yes, I'll take the casters up and have it rest on feet when in use.

I will have a Veritas double screw end vise at one end, and rows of dog holes in a pattern across the top. I also want a front side row of dog holes, and plan on installing a skirt about 2 1/2" high along the sides for looks and so I've got a wider clamping surface on the side. The original plan was to glue a sheet of 3/4" MDF to the back of the maple top for the added mass and rigidity, and this would give the side dog holes a completely filled areas to be bored into.

I know getting the MDF glued to the maple top is somewhat tricky in that A) I have one chance to get it right, B) if everything's not level and square I can pull the maple top out of square, and C) it makes the whole assembly heavier.

I can take care of the skirt question by laminating a narrow 3" strip of MDF behind the skirt around the perimeter, so that's not the pivot point of the matter. The question is, is the added rigidity of the extra 3/4" material worth the effort for this application?

[Robert Rozaieski]

I'd say no. MDF is not rigid at all. The maple is much more rigid than the MDF. MDF will sag horribly over a long length like a workbench without a lot of support. I think you'd do more harm than good by adding the MDF. The extra weight would be nice, but the maple will be stiff enough on its own; far stiffer than MDF. Solid wood is far stiffer than MDF, ply, osb or any other manufactured wood material.

[lowell holmes]

Is the top 1 3/4" thick at the edges or all the way accross. You need mass in the base also. You can't have a bench skidding about when you are planing a board or tipping when you put an eccentric load on it.

A 1 3/4" top on a base that is m&t 4x4 or 6x6 wood is what many in this group have. There are reasons why they have it.

I have a 72 x 24 X 1 1/2" thick maple top mounted on a base of 4x4 legs with 2x6 aproms. It is really stiff and most of the time has enough mass to stay put. On occaisions it will move on me. I think my bench is at the bottom of the list on stability.

I don't see a problem with laminating mdf to the top, but if your base is not stiff, you will regret it.

[Joe McMahon]

Would the glued MDF move with the solid maple? I ask this because if the MDF doesn't move with the seasonal changes, either it will delaminate, or the top will split.

I've never glued MDF to solid wood so I have no experience here but the question did come to mind

[Owen E Wheeler]

1 3/4" all the way across. The base is what it is, and not all that massive, the Noden's design is a sliding height arrangement that lets me raise & lower it for various uses. The mobility of the casters, out of the equation when the bench is parked, is important to my shop use too. I was aware of the mass of 4x4 & 6x6 leg assemblies on some benches and the advantages thereof, but that kind of bench would not have been achievable for me, nor fit my shop.

I guess I could build a shallow torsion box below the maple instead of a sheet of MDF. That would give me more stiffness (dependent on the outcome of this discussion) without adding that much height to the total. Build the torsion box square & flat, add the maple top to the top, shim if needed to bring the two into perfect parallel alignment, and attach. The skirt could be made taller to meet the size of the torsion box.

I'm not looking for added work here; this is a means to a end. I want a nice bench in place to work on, and don't want preventable, foreseeable problems and regrets when I'm done.

Thanks in advance for everyone's thoughts.

Edit....

On the Noden's base rigidity, I'm convinced it will be fine. A) I'm a skinny 170, so what I do with a plane will not likely be scooting any bench around a shop much. B) I've seen the Noden live and in person. It was resting not on feet but directly on a wood floor, and didn't move at all under some lateral loading. John Economaki (sp?) of Bridge City Tools was doing a demo on it, and commented on how he liked it. FYI the bench was in use at the furniture designer the tool show was being held at, and Noden was not there, nor had John ever heard of Noden per his comments. C) I've looked at the Noden design and am convinced that the nature of the locking mechanism and the cross bracing make the 3 dimensional total of the base plenty stiff for lateral loading, at least of the level I'll be putting on it.

[Jeff Johnson]

Why not just attach larger (say 2"x2") pieces of maple around the bottom of the top? (screws with expansion capacity on the end pieces to preclude splitting) That'll give the nicer edge, and a better surface for clamping and for side dogs. And to give your top dog holes substance, attach either another maple 2x2 or even good straight (acclimated) strips 2x4s of douglass fir or whatever inexpensive lumber you can get along the underside where the dog holes are going to be. There'll be a potential difference in seasonal expansion with different woods, but that's linear, so no big delta. And no way are a couple of pine 2-bys going to out-power a thick maple top.

[lowell holmes]

Sounds like you have it covered. I wouldn't worry about adding mdf. I don't think it adds anything.

Enjoy your new bench. Let us know how it performs after you get it.
:)

[Steve Schoene]

Sounds like you are still trying to attach something that doesn't shrink and swell with humidity changes, the torsion box, to something that does, the maple top. That's a receipe for problems. It means you couldn't really attach them firmly but would have to allow the maple to change width independently.

You could however, glue maple beams, running in the same direction as the grain in the maple top, to the underside of the maple, essentially creating a I-beam structure. (U-beam really.) This is common on workbenches with wide aprons, though I've generally though having the extra depth of the aprons was to provide an additional mode of clamping to the bench. They couldn't be attached to the breadboard ends.

Frankly however, I think you are over thinking. The 1 3/4" maple top is going to be plenty stiff, I'd bet. I'd try it for a while before retrofitting extra stiffening beams.

[Andrew Pitonyak]

A) I have one chance to get it right, B) if everything's not level and square I can pull the maple top out of square, and C) it makes the whole assembly heavier.

I can take care of the skirt question by laminating a narrow 3" strip of MDF behind the skirt around the perimeter, so that's not the pivot point of the matter. The question is, is the added rigidity of the extra 3/4" material worth the effort for this application?
Do not be hasty. I recommend that you assemble and use the bench before making changes, especially changes that are not easily undone. In my mind, the most serious limitation is the potential lack of weight in the base.

[george wilson]

I was at Costco yesterday. They still have a workbench with a 1 3/4" maple top 8' X about 30",with a substantial steel tubing base. The bench was about 10' off the floor,so I'm GUESSING ABOUT DIMENSIONS. The base is 3" square steel tubing,with steel cross members. It looked pretty substantial for a cheap bench,and was only $199.00. The top is worth that,even if it's glued up short pieces,for an INEXPENSIVE bench.

[Chris Friesen]

With a 1 3/4" bench, I would suggest making sure that any pounding you do is as close as possible to directly over the base. I have a 2 1/2" thick mable bench top and it still makes a noticeable difference if I pound over the legs or out on the end of the overhang.

Someday I'd like a 4" thick bench top. :)

[Owen E Wheeler]

Great advice, and thank you all. I wish the forum I participate on professionally (high end home automation) was as welcoming to completely green newbies.

I won't attach anything to the maple of a dissimilar type or direction to grain, thanks for pointing that out.

I will do my pounding near one of the legs.

I won't be expecting granite-foundation-tied-to-the-core-of-the-earth stiffness, but will be looking for less than the 1" or so wave when planing I get from my current hand me down mass market woodworking bench.

I do want to do a skirt, to dress this puppy up slightly. It will be maple, and outside of the end where the twin screw vise goes will be at or very near the 1 3/4" thickness of the top.

Thanks to all for their input. I'll post pictures when I'm finished with this. :-)

[Stephen Cherry]

One option might be to get a costco maple bench for the top, and place that between the Noden base and top.

[Eric Brown]

My bench has the Noden legs and twin screw vice. Here are things I did:
1. Added leveling pads for bench to sit on.
2. Added 6" skirt flush with front vice back jaw.
3. Made twin screw wide enough to go aound Noden legs.
4. Made stretchers real tall and added plywood board at bottom for storage/weight.
5. Laid out dog holes to avoid interferance with legs and vices.
Note: Made one mistake, drilled holes in skirt on same alignment as the top. There are times when dogs/holdfasts interfere. Should offset a little.

Think you'll like the legs.

Eric

[david m carter]

Johnny come lately here.

I use a rescued 1 3/4" maple top as the basis for my 32"x72"hand tool/assembly/outfeed bench, and found it much too lively when pounding the larger mortise chisels. Gluing two 3"x3"x44" maple ribs to the underside, spaced about 1/3 of the way in from the edges, greatly improved the rigidity, it now responds with a dull thud and no obvious vibration when vigorously struck.

I can't see where MDF offers any structural value in bench top construction.

[Owen E Wheeler]

My bench has the Noden legs and twin screw vice. Here are things I did:
1. Added leveling pads for bench to sit on.
2. Added 6" skirt flush with front vice back jaw.
3. Made twin screw wide enough to go aound Noden legs.
4. Made stretchers real tall and added plywood board at bottom for storage/weight.
5. Laid out dog holes to avoid interferance with legs and vices.
Note: Made one mistake, drilled holes in skirt on same alignment as the top. There are times when dogs/holdfasts interfere. Should offset a little.

Think you'll like the legs.

Eric

Great!! Much good info there. If I could get these pesky customers to stop calling I would start on it today. :-)

[Will Blick]

Eric, thanks for your contribution....

What do you mean by "leveling pads".... I assume this is something to keep the top from becoming bent by uneven Noden contact points not being true? Where do you buy these?

Any pix of the finished bench? I am planning to add the same to my set up...

TYIA

[Shawn Albe]

I was at Costco yesterday. They still have a workbench with a 1 3/4" maple top 8' X about 30",with a substantial steel tubing base. The bench was about 10' off the floor,so I'm GUESSING ABOUT DIMENSIONS. The base is 3" square steel tubing,with steel cross members. It looked pretty substantial for a cheap bench,and was only $199.00. The top is worth that,even if it's glued up short pieces,for an INEXPENSIVE bench.
I have this one and can measure it if needed. It's pretty solid, but vigorous planing causes it to shake a bit. But it is good for general shop work, and as George said, you could just take the top. One things, it is a HEAVY package to load in and out of your vehicle.

[Eric Brown]

Here are a few posts you can follow. In them I have pictures and descriptions. If you need more info let me know.
http://www.sawmillcreek.org/showthread.php?p=1369471#poststop
http://www.sawmillcreek.org/showthread.php?p=1009101#poststop

Eric

[Will Blick]

Thank you Eric....

I was confused... I thought by leveling pad, you meant between the Noden and the top. I had a flat maple top, but the Noden mount points were not in the same plane, now the top is not level, so I will have to loosen lags, and possibly shim it, if possible, maybe the top has given way.... I keep using the bench, but never really finished it....

I loved the design of your bench, mine will look very similar when done... I am curious if you have any tips, or things you would do differently now that yours is finished?

BTW, the center dark accent woods, did you dado a groove and insert a thin piece of the accent wood? If so, how thick was the insert wood? Sure is pretty... TYIA

[Eric Brown]

The dark bands are actually solid walnut boards 1" wide by 3" thick glued to the maple boards. Basically I used the 7 3/4" dog spacing of the Tucker vice as the spacing for all the dog holes. The maple boards were adjusted to have the walnut boards centered on the dog spacing. Same spacings were used on the 6" walnut aprons. BTW, the Veritas hold downs clamp at about 8" and many of the other holdfasts are closer to 7". Sometimes I wish that either the holdfasts were longer or the dog spacing closer. Usually my solution is a repositioning of the work. The other thing I mentioned before is the interference of the top and apron dog holes. Should have offset the apron ones. Other than that I love my bench. Just wish I could spend more time with it.

Eric