 Build a Portable Workbench
Does this happen to you? You're working on a project somewhere in the house, and you have to trim a board to length. You can't figure out how to hold the board firmly, so you lug it back to the shop, clamp it to your workbench, make the cut, and trudge on back to the job site. Then the fit isn't exactly right, so you have to make the whole round trip again. If this happened just once in a while it would be annoying enough, but it happens to me all the time.
Sometimes it seems like I spend more time walking than working. I got to thinking how ridiculously inefficient this marathon is, and how simple it would be to solve. The missing piece is a workbench that can be moved easily to the job site. With a sturdy bench nearby, I could handle routine woodworking operations quickly, accurately, and without unnecessarily wearing out my shoes — or my temper. Advantages A portable workbench still has to pass muster, or it won't help get the job done. It has to be rigid, sturdy, and large enough to support a variety of workpieces. Plus, it has to knockdown easily.
My design satisfies all those requirements. And I built it using common materials from the building center: standard framing lumber, hardboard, one sheet of medium- density fiberboard (MDF), a vise, and some hardware.
Portable Workbench Plans
- OVERALL SIZE: 251/2"×331/2" × 60" (Dimensions do not include vise or levelers.)
- Top 1/2" x 24" x 58-1/2"
- Banding 3/4" x 1/2" x 25-1/2"
- Upper support 3/4" x 1" x 10-1/2"
- Lower support 3/4" x 2" x 10-1/2"
- Upper rail 1-1/2" x 4-1/2" x 22"
- Banding 3/4" x 1-1/2" x 60"
- Upper Vise support
- Lower rail Leg leveler 1-1/2" x 4-1/2" x 22"
- Bolt Shelf 3/4" x 12" x 40" MDF
- T-nut 1/4" x 20
- Pronged T-nut Leg 1-1/2" x 3" x 32"
- Stretcher 1-1/2" x 3" x 42"
- Hardboard Draw catch 1/8" x 3" x 42"
- Chamfer edge Stabilizer
Half Lap Joints
As I mentioned, the leg frames are held together with half-lap joints. Half-laps are one of the simplest joints to cut and fit. And, with the addition of both glue and screws, they provide plenty of strength for this application. As the name implies, the depth of each half-lap should equal half the thickness of each joint member. Although these half-laps are wider than any dado blade, making multiple passes with a 1/2" wide blade goes quickly enough. Install the blade in your table saw and, before ever cutting into your actual project stock, cut half-laps into a spare 2" × 4" until you have the blade height set perfectly. Half-lap joinery in the leg assemblies provides great strength and rigidity, and the use of hex head bolts and T-nuts allow quick assembly and disassembly of the bench.
Cutting half-laps is easily done with a dado blade. Raise the blade to half the thickness of the stock and make multiple passes. Lay out the half-lap locations on the legs and cut the joints. Begin with the half-lap for the lower rail joint. Clamp a set up block to the fence and cut the lower shoulder of each half-lap first. Then, move the fence a little further from the blade and make a second pass, and so on, until your cutouts snugly fit the width of the lower rail. Now, set the fence and cut the half-lap in each leg for the upper rail. After you complete the leg cuts, cut half-laps at the ends of the rails
Workbench Vise
Besides the broad work surface, the feature I use most is the vise. It's not as heavy-duty as the one in my shop, but for on-site work it's more than sufficient.
Building the Leg Frames
To get your portable workbench underway, I recommend starting construction on the leg assemblies. To keep the cost and weight down, I built mine using common softwood framing lumber. Select 2" × 4" stock for the legs and stretchers, and 2" × 6" stock for the rails. For now, cut the pieces an inch or so longer than their final size. All of us who work with construction grade lumber know it can be rough, and the width often varies. But a workbench is more refined than the framing for a wall, so I wanted crisp, uniformly sized wood. Therefore, to square up the stock, I ran one edge of each piece over my jointer, then trimmed the opposite edge on the table saw. I suggest doing this to your leg and rail stock now. But leave the stretchers until later, after completing a few other preliminary steps. Once you've squared these pieces, cut them to length.
Making the Stretchers
You might think that 2"× 4"s alone would be sufficient for the stretchers. I found out the hard way that they're not. When I first built my workbench I just notched 2"× 4"s and fit them into the leg frames. Then I pushed a little on one frame, and heard a snap as some of the small tips at the ends of the stretchers broke. That little bit of long grain in the tips just couldn't hold up to any stress. So I went back to the drawing board and came up with another idea. By sandwiching the 2" × 4"s between pieces of 1/8" thick hardboard, I reinforced the small tips and added lots of rigidity to the stretchers overall. This construction has proven to be very strong on my workbench.
Rip a half dozen 3-1/2" wide strips of hardboard and glue them to the lumber you selected earlier for the stretchers. Since I have a limited number of clamps, I grouped all three assemblies into one large sandwich and clamped them at the same time. I recommend using scrap 2" × 4" pads to protect the outside of the sandwich and help spread the clamping pressure evenly on the assembly. Using waxed paper between each stretcher will keep them from accidentally bonding to each other. Clean off any excess glue once it dries to a rubbery consistency. A putty knife will usually do a fine job. Next, joint one edge of each stretcher and trim the opposite edge on the table saw. The final width is 3". Rail and Stretcher Notches Notches in the rails and stretchers combine to make another set of halflap joints. Cutting these notches is easily done with a standard blade in your table saw — just make multiple passes to remove the waste.
Lay out the notches on the upper and lower rails and set the height of the blade. While you're at it, lay out the notches on the stretchers as well. Cut notches in the rails first, checking their fit on a stretcher after every pass until the fit is snug. I recommend cutting one end of each notch with your first pass, then nibbling your way on pass at a time to the other end. Complete the rail notches and move right into the stretcher cuts.
Drilling Accurate Holes
The stretcher-to-rail joints are the central knockdown feature of this workbench. Each of these joints is held together with a bolt and a T- nut. The key to making this system work is accurately boring the holes for the bolts so they pass through the rails and stretchers easily. Holes that aren't plumb or square to the joints will bind the bolts and cause frustration — you'll have to mess with a hammer for driving the bolts into place, and you'll need a pair of pliers to pull them out.
Begin by marking centerpoints for the holes on the back edge of the stretchers. Make sure the mark is directly opposite the center of each notch. Next, using a drill press and a 3/4" bit (a Forstner bit works best), drill counterbores 3/4" deep. Then, change to a 5/16" brad-point bit, and drill the rest of the way through the stretchers. Don't forget to reinforce stretchers.
Stretcher
Cut notches after stretcher and hardboard are assembled. to back up your stretcher notches with a piece of scrap wood, which will minimize the chance of tear out as the bit exits the wood. For future reference, I used an indelible marker to write a number on each joint member so I could always put them together in the same order. After marking the pieces, position the stretchers on the rails. Now, you can mark the hole locations on the rails. Remove the 5/16" drill bit from the drill press and put it through a hole in the stretcher. Then, tap it gently with a hammer to mark a centerpoint. Repeat this procedure for each joint. Next, re-chuck the 5/16" bit in your drill press and bore the holes through the rails. Here again, remember to position scrap wood under the workpiece to prevent tearout. After drilling the holes, drive a T-nut into position. Center counterbore and pilot holes on notches. Cut 1-1/2" x 1 !/2" notch 1" from end.
Leg Frame Assembly
I always enjoy the assembly part of my projects. This is the time when all my hard work pays off, and the pieces slip together perfectly (or at least they do in my dreams). Assembling the leg frames for your workbench is a very straightforward operation. First, clamp the rails and legs together, making sure the assemblies are square. Then, drill countersunk pilot holes for four screws at each half-lap joint. Now, remove the clamps from the frames and spread glue on the joints. After repositioning the pieces, drive a screw into each half- lap and check the assemblies for square. Once you're satisfied that everything is set, drive the remaining screws and lay the frames aside for a few hours while the glue dries. For each stretcher to rail joint, drill the coun-Tap a pronged T-nut into the hole in the bottom Spread glue on the half-lap joints and drive terbore first, then drill the 5/16" pilot hole. Use edge of each upper and lower rail. The T-nuts one screw into each joint. Square the assema drill press to accurately align these holes.
Making the Workbench Top
Building a top like I did requires two layers of medium density fiberboard (MDF). This construction is very solid, and does not allow much "bounce" — an important quality whenever you're banging on your workbench with a mallet or hammer. The downside is weight — MDF is heavy. For a lighter, but bouncier, top, you can use plywood or a single thickness of MDF. If you decide you want a top like mine, cut two MDF panels about 1/2" larger than their final size, then lay one panel on top of the other. Now, drill countersunk pilot holes in rows about 10" apart along the length of the panels. After drilling all the pilot holes, separate the panels and spread glue on both pieces. A short-napped paint roller will make quick work of this chore. Reposition the panels and drive #8 × 11/4" screws into the holes. In a few hours, after the glue dries, trim the top assembly to size and rip the maple edge banding. Cut the banding to length, miter the ends, then glue and nail it to the MDF — be sure to drill pilot holes for the finishing nails. Routing chamfers on the edges gives the top a finished look.
The Accessory Shelf
Cut the remaining MDF to size for the shelf. I routed chamfers on the edges to match the workbench top. The shelf sits on the lower stretcher with help provided by a pair of stabilizers — they keep the shelf from slipping off the stretcher. Cut 2"× 4" stock to size for the stabilizers and, for good looks, chamfer the edges on one surface of each piece. Now, lay the shelf upside-down and center the lower stretcher on it. Once you're sure the stretcher is perfectly centered, clamp the stretcher to the shelf and set the stabilizers alongside. I like to slip playing cards between the stretcher and the stabilizers to allow a small margin for wood expansion and to ease the fit. Drill countersunk pilot holes into each stabilizer, then glue and screw them to the shelf.
Final Assembly
Drill holes for T-nuts into the bottom of each leg. Tap them into place, then add the leg levelers. Erecting the workbench is now a simple matter of connecting the leg frames with the stretchers, then adding the top and shelf. Begin by slipping the stretchers into the notches in the leg frame rails and tightening the bolts. The base assembly should now feel solid. Next, lay the top upside-down and center the base on it. Cut 2" × 4" stock for the supports, and screw the upper support to the top after drilling countersunk pilot holes. Set the lower supports into position and screw them to the leg frames. Install the catches and you have an ideal knockdown mechanism for the bench top.
By releasing the catch, the workbench can be disassembled and moved. The accessory shelf, with its attached stabilizers, fits over the lower stretcher. The shelf provides an ideal place for setting tools. The Vise While the workbench is still turned upside-down, you can easily install the vise. The model I chose does have a couple of features that require some accommodation on the bench top. But once these details are completed, the vise will be flush with the surface of the top, allowing an unobstructed space for laying a sheet of plywood or a door. The first item to attend to is a spacer. The spacer positions the top edge of the vise jaws flush with the bench top surface. The spacer thickness in this plan allows for two layers of MDF in the top. You will need a thicker spacer if you made a single layered top.
Machine the spacer to size, then position it with the vise on the underside of the top. Now you will notice the second accommodation for installing the vise. The back of the rear vise jaw is slanted. So to install the back tight against the bench top, you'll need to excavate a shallow mortise. Use a knife to mark the vise location on the banding, then remove the waste with chisels. Be sure to slant the mortise to match the shape of the vise. Now, press the vise tightly into the mortise and drill pilot holes for the lag screws that hold the vise and spacer to the top. I recommend using a stop collar on your drill bit to make sure you don't drill through the top. Secure the vise to the top and turn the project right side up.
Wrapping Up
This workbench doesn't qualify as a piece of fine furniture, but after all the work I put into it, applying a couple coats of varnish seemed more than justified. The varnish seals the project and protects it from moisture and dirt. Within weeks of completing the workbench, and after moving it several times, I came to appreciate just how valuable the knockdown feature is. The catches are especially easy to operate. And the bolts take just minutes to dismantle. Although I don't always set up the shelf, it still comes in handy when the bench is moved to a site for a long period. It's a good place for keeping tools off the floor where they could be damaged. No matter where I work, the portable workbench more than earns its keep. In fact, when it's nearby, I've even used mine as a serving table in the dining room. Now that's versatility!
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