For years I've always struggled with building workbenches and workstations, most of the time they ended up with the legs uneven or over time becoming unstable and a little wobbly. I've seen a lot of designs using a single 2x4 stud for each leg, using big bolts and washers, ultimately costing more and still feeling unsure if I should put it against a wall to prevent tipping over or worse, falling apart!
A couple of years ago I came across a leg design that led to the most stable bench design I have built thus far, and after building over 30 of these at sizes ranging from 2 foot wide by 4 foot long to 4 foot wide by 20 foot long; I have found they can sit anywhere from out in the middle of the shop to taking heavy abuse by cleaning crews at my work. So much so I have had as many as 6 large people standing on the big benches held together with cheap construction screws, working overhead without a single fear of failure!
The Super Stable Work Bench!
Step 1: Materials and Tools Suggested
To complete this project there are a few tools that are needed:
Drill (Any type as long as it has the torque to drive the screws)
Drill bit (My favorite is a drill and driver, just flip the drill bit and drive the screw)
Screwdriver (A screwdriver bit for your drill saves the time and the hand pain)
Saw (A circular saw is the best for plywood, but a miter saw gives nice clean stud cuts)
Clamps ( Various types, 6" C-clamps, quick clamps, and bar or pipe clamps are the best I've found)
Marking Utensil (Just a pencil will do)
Tape Measure (Anything over ten feet will do)
2x4x96 Studs (The amount depends on the size bench you want to build, but a 4x4 square bench will use roughly 8 to 9 studs at 96" long)
Wood Sheeting (Plywood is the best, however OSB, and even 3/4 thick melamine will work too!
Various sizes of screws ranging from 1 1/2" to 2 1/2"
Not particularly needed tools (But if you have them they can be a great help):
Square (I use a speed square for most everything)
Straight edge (or even a chalk line)
Level (With this design it's not really needed but its nice to double check)
TECH TIP: Remember the old adage "Measure twice cut once"
Step 2: The Cuts
For these pictures I am building a 2 foot by 4 foot bench, 3' 5/8" high. All of the sizes needed are available in the PDF, when you finish you should have 18 boards ready to assemble.
While this is a fairly small workstation style bench the length and width of the bench can be extrapolated to almost any size by adding to the shelving supports.
If you measure and cut the 2 "Side Inner Shelf Supports" to 87" and cut the 2 "Side Main Table Top Supports" to 93" you'll end up with a bench 4' by 8' making the table top fit a standard size piece of plywood.
TECH TIP: Before making you cuts use a marking utensil such as a pencil or marker and layout all of your cuts first on the boards to save how much scrap wood you'll end up with! Don't forget to calculate in your saw blade kerf (thickness).
Step 3: Leg Design
A few years ago I came across a wooden shelf that someone had built the legs using this L shaped design and it occurred to me this would work for a workbench as well.
Using the previous PDF, making your wood cuts at 36" for 8 boards.
Once you have your cuts, using a couple of C-clamps, clamp the 1 1/2" short side of one board to the corner of the 3 1/2" long side (A standard 2x4 is actually 1 1/2 x 3 1/2, or to be more precise 1.525 x 3.525), make sure you square up the ends.
Pilot drill 3 screw holes through the opposite side of the 3 1/2 long side into the 1 1/2 board
TECH TIP: Using a standard 96" stud; take the time to measure and cut each 36" leg from the stud at each end, in case your cuts aren't exactly square you'll at least have one end that is making a nice flat edge against the floor!
Step 4: The Inner Shelf
Every workstation I have built includes an inner shelf, not only for support and stability but also to have a storage area for whatever I'd like to have handy while working.
Referring back to the PDF; the entire bench design stability relies on the overlapping of each of the board ends intersecting with each other, creating a layered design gives a durable build that can last.
Using the 14" cuts (I wrapped them in tape to remind me not to screw them in) place them in the inner side of two of the legs and clamp them to the leg, creating supports for the first brace.
Next add the "Side Inner Shelf Brace or 15" cuts" laying it on each of the 14" supports, then clamp, drill, and screw the brace in place. It's helpful here to have a level to make sure the legs are square, however the nature of many of the studs being less than true it does always work, and the rest of the design when built will automatically correct the little imperfections.
Build the opposite side legs the same way by clamping the 2 supports and brace; then screw the brace into place as well. you should now have 2 identical bench sides.
Before removing "both" of the 14" shelf supports move only one back over to the previously built bench side and clamp it back in place, now you have the supports for the "Front and Rear Long Inner Shelf Brace or 42" braces"! Following the same clamping and screwing method attach both front and rear inner braces with the 2 1/2" screws.
TECH TIP: Using a quick flip drill and driver really adds to the build, many of these come with a countersink built in which hides the screw heads well giving a more finished look plus it gives you the option to fill the holes and stain the bench if you so inclined to do so.
Step 5: The Table Top Braces
This is the point where all the strength of the bench comes together and adds the corrections to the imperfections I mentioned earlier.
Starting with the "Side Tabletop Braces or 21" cuts" using a square line up and clamp the side braces to the outsides of the top of the legs, pilot drill, and screw these in place.
Next square and clamp the "Front and Rear Long Tabletop Braces or 48" cuts" in place and finish the frame by going over the entire frame adding screws in places that you feel may require an additional fastener.
TECH TIP: Wood (even kiln dried studs) are not perfect many times they are warped, twisted, scarred, cracked, lots of knots, and just often untrue! You will have to use a little elbow grease; pushing and pulling to get these to line up, but I've found that only adds to the strength from the resistance. As you may notice I built this bench with some wood I reclaimed from another project which added a whole other level of difficulty, so don't be afraid to get a little tough with the wood.
Step 6: Finishing with the plywood
At last the fun part, Adding the plywood shelf and table top!
The inner shelf in the PDF will not be exact, because the wood is never perfect you'll have to measure your frame to be sure but it should be close. Once you have "your" exact measurement using a tape measure and a chalk line layout your cut lines on the plywood and make your cuts using a circular saw.
Once your inner shelf is cut to size lay it inside the L's of your legs, fitting like a glove! Pilot drill and screw the shelf down using the 1 1/2" screws. As you'll note I used a piece of scrap melamine board on this bench simply because it's what I had available at the time trying to use up scraps around the shop.
Finally measure your table top frame and transfer that measurement to the remaining plywood using chalk line and then cut to size with your circular saw. Place and screw down the table top to finish the bench.
TECH TIP: If you want to be overly cautious on strength, adding wood glue to the inner shelf and table top for a more permanent solution can be nice touch! Also don't worry to much about the blade kerf on your inner shelf plywood cuts I've found sometimes it helps to have a little play to make it fit well.
Step 7: On To The Next Project
The great thing about this bench design is it can sit anywhere, it can be modified to add tools, it has the flexibility to add on side tables or an overhead shelf. Since I have built dozens of these workstations for device cleaning crews, shipping and receiving departments, and for my own workshop I have seen these take an immense amount of abuse. I have built hundreds of projects on these benches (some of which are pictured) and they can stand the test of torture and time.