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Assembling parts is easiest when you can work at a comfortable height. But the height of that working surface depends on the size of the project. These ABC boxes, so called because they’re made with sides of three different dimensions, make a variable-height assembly table base. By rotating the boxes or standing them on end, you’ll get three different working heights.
Plywood Cutting Lengths
A—6" x 15"
B—6" x 24-1/2"
C—13-1/2" x 24-1/2"
For stability, you’ll need three boxes; it’s best to fasten them to the top. All three boxes can be made from one 4x8 sheet of 3/4-in. plywood.
3 Work Heights
This table is made from a full sheet of 5/8-in. plywood for the interlocking base stand and a sheet of 3/4-in. plywood for the work surface and shelves. You’ll also need four 10-ft. lengths of 1x3 pine for the edge banding and cleats.
Cut two 30-in. high by 48-in. long pieces from the 5/8-in. plywood for the base pieces. Then cut a slightly over size 5/8-in. wide slot in the bottom half of one base and in the top half of the other. Make both slots about 15-1/2 in. long.
Assemble the base and position the top so the corners are aligned with the legs.
Screw loose-fitting 12-in. long 1x3s along each side of each leg to hold everything stable.
The table is much more stable if you use the 3/4-in. waste from the top to make triangular braces (which also act as shelves) with 20-in. long sides. Using 1-1/4 in. drywall screws, attach 1x2s to the base about 12 in. up from the floor and screw the shelves down.
This space-saving design is made from a salvaged prehung door. Not only does it take zero floor space because it’s mounted against a wall but it also has built-in Peg-Board tool storage so your tools are right at hand when you fold open the door.
You can often find damaged prehung doors at the lumberyard for cheap. Look for a flush, solid-core door with the jamb attached. A heavy, sturdy solid-core door provides a strong attachment base for the bench legs and is tough enough to take a pounding.
Reinforce the jamb corners with 1-5/8 in. drywall screws and add a board across the bottom where the threshold would normally be. Screw a 1 x 4-in. flange onto the back edges of the jamb with 2-in. dry-wall screws. The jamb is hung on the wall with 3-in. drywall screws. For a comfortable working height, hang it at 36 in. for stand-up or barstool work. Screw Peg-Board to the over-hanging flange that’s inside the opening. Make two legs from 3/4-in. threaded pipe and screw them into two 3/4-in. pipe flanges to support the workbench when it’s down. Support the bottom jamb with angle brackets and add a hasp to hold the door shut and keep it from falling open.
If you ever need a light-duty work surface anywhere in the house for sewing, painting or school projects, this one’s for you.
Get to the home center and buy a hollow-core door; four toilet flanges; a 10-ft. length of 3-in. PVC pipe; 16 No. 10, 1-1/4 in. long screws and a tube of construction adhesive (total cost about $40).
Inside of a half hour, you’ll have the flanges glued and screwed to the door and be ready to slip in the 30-in. long PVC legs.