Hello,
As much as I would love build a big ol’ woodworking bench for the middle of my shop, I need to get some stuff organized over on the sides first 😉 My current ‘workbench’ is a 30×72″ Craftsman w/ a 1-1/2″ MDF top and sheet metal sides. Worked well enough for reloading, but w/ woodworking joining the list of hobbies, I figured this is as good a time as any for a remodel.
What I have in mind is a workbench that runs the majority of the length of one wall of my shop, from the door to the corner, or about 15′. Cabinets/shelves above, and roll-around cabinets underneath (pretty much like the set up in the workshop featured in the recent Tools-n-Shops issue of FWW ‘Rollaway Workshop’. I’d had that sort of idea in mind already, but that more or less confirmed the direction I was heading. I’m looking at having the top constructed from at least 3 layers of 3/4″ plywood, w/ a hardboard top cover for ease of replacement.
My questions come along the lines of a) making sure that I have this thing sturdy enough b) the frame will support the beast w/o looking too hideous, and c) positioning a front vise at the left corner.
The sturdiness question comes in because I have a bench made of 2 thicknessess of 3/4″ ply glued and screwed together w/ 1/4″ hardboard for a top out in the ‘main’ (auto/general purpose) shop. At one point in time I had to move my reloading presses out there, and was not happy at the amount of flex I noticed while operating the press (attached w/ C-clamps) on that bench. Is 3 thicknesses going to be enough? Would 4 be overkill? MDF a better options?
As far as making sure the thing stays up… I figured on some sort of frame legs every 3-4 feet. Not sure about whether to go w/ a ‘trestle’ type of leg i.e. more of an open heavy frame w/ 3-4″ members, or just build an ‘H’ out of 2×4’s and screw-n-glue some plywood over the outside to stiffen them up? After that, I was figuring on some sort of 2×4 frame on top of the legs, to support the laminated top. Or would that not be necessary w/ the closer spacing (3′)? Like I mentioned, this is a *work* bench, so I’m not looking for furniture grade appearance here, but I do want something that will look reasonably decent. It will be attached to the wall in some fashion so that it doesn’t move, and so I don’t get stuff down the crack btwn the two. Any suggestions as to mounting solutions? The wall is a load bearing 2×4 wall, covered w/ drywall.
Then the vise… I was leaning towards a ‘large’ all-metal quick-action vise like the Record from Woodcraft. Figured I’d have the last 12″ or so of the bench top overhang the last ‘leg’ and attach the vise there, w/ a single row of dog holes going across the bench towards the wall, and maybe add a row along the edge down the length later…? Is that enough space for the vise, so that it wouldn’t interfere w/ the legs?
Anywho, I guess the design is still kind of flexible in some areas. Any input, comments or suggestions welcome.
TIA,
Monte
Replies
Stiffness in a top is primarily a function of thickness, a panel twice as thick will be four times as strong. Stacking up plywood or MDF is the hard way to get a thick surface, even four layers are still only 3 inches thick.
A better way to build a stiff top is to build a frame out of 2x6's or 2x8's, two long rails with crosspieces every 16 inches or so. Glue a single layer of good quality 3/4 inch thick plywood, such as Baltic birch, onto the top edge of the frame an you'll have a very stiff bench. To protect the plywood the cover it with a disposable piece of hard tempered Masonite.
Set up this way, you'll only need a leg every 6 to 8 feet along the edge. Notch one of faces on each leg so that the 2x frame sits in the notch for maximum strength. On any bench, the top is always the most solid directly over the legs, so that is where you should place a piece when you are hand chopping mortises or dovetails.
John W.
>> ... a panel twice as thick will be four times as strong.
But eight times as stiff. Strength increases as the square of the thickness. Stiffness increases as the cube.
Its been 30 years since I studied structural and strength of materials so I'll have to take your word for it. Thanks for the correction, I'll have to find a good basic text and refresh my memory on the subject.
John W.
No correction, just an addition. :)
would a bench top made from a frame and a single thickness of plywood be sufficiently strong regarding dog holes? What about edge at the edge, for stuff being clamped to the edge of the bench? The other option that had came to mind for construction was perhaps using solid lumber, either in the form of something simple, such as 2x10 or 2x12 planks side by side, interlapped so I don't have to deal w/ a 15'+ 2x12 and the possible warpage, or else some sort of top built out of smaller dimensional lumber laminated together in such a way to make a top similar to a regular woodworking 'butcher block' top. My concern there is possible damage from chemicals/solvents etc. as this is not going to be used for *just* woodworking. Guess I could slap a piece of hardboard over the area where I'm working when dealing w/ such liquids as one option.
Thanks,
Monte
Edited 3/16/2004 11:39 pm ET by milanuk
My benchtop is made from 3 boards of 2 x 10 fir, wall mounted, 10 feet long. It's about 20 yrs old. Organic chemical solvents like MEK, acetone, paint thinners, xylene, toluene and the usual run of chlorinated solvents haven't even marked it. H2SO4 chewed it up a little but a quick neutralization with sodium carbonate stopped the attack. The earthquake of 1993 or 94 dropped and broke a bottle of conc. HNO3 on it, and it was 4 hrs before I neutralized it. There was some damage but not enough to replace the top.
That's good to hear, Rob. Did you have your boards coated w/ anything? poly, paint, ???
TIA,
Monte
No coating at all, just raw wood. I periodically clean it with a wet rag and wipe it dry. The part where the nitric hit is sort of blackened. The support for the top is a 2 x 4 framework tied into a long 2 x 4 lagged to the wall (2 x 4 framing with 5/8" drywall) and the front legs are 4 x 4 fir screwed to the concrete floor with L-irons. The top overhangs the front legs by about 1.5" so if I really have to pound on something I can put it over one of the 4 x 4 legs. The legs are 30" apart.
Do you have a vise (woodworking or otherwise) attached to this plank top? Any problems w/ flexing? Maybe I'm not envisioning this correctly, but it seems like w/ a 2x4 frame underneath, the only way to get clearance for a woodworking vise would require an overhang off one end, where the planks don't seem like they'd be very stiff?
Thanks,
Monte
Let's call each space between the legs a "bay". I have a 2 screw woodworking vise mounted in the bay on one end, with a bocote jaw which closes against the lip of the 2x10 at the front of the bench. This way, with a temporary support at the far end I can clamp a board up to ten feet long and work on it. Under the vise I use the rest of the bay to store my gas welder (small bottles on a wheeled cart.) The other bays have drawers, cabinets, toolbox shelves, etc. The metalworking vise is mounted into the 3/4" OD-3/8" ID steel threaded inserts from RCMC and is removable in about 30 seconds. The bench runs wall to wall and there's no flex because the ends are fixed to a wall mounted 2x4 at each end. After 20 yrs of acid spills, pounding, weldinf splatter etc. this is not a bench that FW is going to feature, but it is still as solid and flat as the day it was built.
milanuk ,
Well we all certainly have ideas and opinions , that's what's so fun about this forum. I will share what a builder pal of mine did for a client that wanted a long work bench such as yours. He simply ordered a glue lam beam , if you will. He was able to order it to the exact thickness that he wanted . With a bit of sanding and a coat of poly or something it really looked great. Perhaps the price will surprise you .If you stacked 3 - 3/4" panels 30"x15' that is 6 sheets plus two more sheets of whatever on top.I think he had it thicknessed to about 2 1/2" It would be difficult to make one any better. My guess depending on the materials you would use your cost would be approximately $200.00 plus your time ,to make it your self .
happy bench working dusty
Now *that* is an interesting idea! Not sure even who to approach about it locally, though.
Thanks,
Monte
milanuk ,
Try your nearest building supply yard. It is not unusual to have an engineer spec for glue lams for structural integrity.So most any yard that sells lumber packages to builders will be able to order one in for you made to your specs.
dusty
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