Sometimes you can look a lot for what you need but you are never totally satisfied. This is the case, I needed three steady long work benches, and it would have been cool if they could also be folded. I wanted them light enough to be moved but sturdy enough to support the movement of a pair of knitwear machines.

Step 1: The Project

So I decided to build my owns with a low budget. You can see the first sketch, which is needed to determine right measures for a height of about 78-82 cm.
The structure shall be composed by many triangles, so to be very sturdy and steady. Classic legs are not good for that. Furthermore, changing the connection holes for legs will vary a few centimeters the height of the table.

Step 2: The Material

Bench boards are made by MDF, which is not the best material you can find, but it's cheap and it's perfect to be painted.
Other bars could be any wood you wish, 20x40 or 30x40mm section, I used both, thinner for surface reinforcement and for crossed braces, and bigger for legs and single braces.
Then you need some bolts nuts and washers, actually twelve bolts 7-8 cm long, all with 8 mm thread. Plus 10 big washers and 10 smaller, 8 self-locking nuts and four butterfly nuts.

Step 3: The Frame

MDF layer is heavy but not very rigid, and to save money and weight I decided to use 10mm thickness instead of a stronger 20mm. Anyway the frame below the plane is needed.
Just cut the bars, glue them in the right position, fasten them with nails and add a bunch of screws from above, before glue gets dry.
From the bar pieces remained cut short 8.5 cm rods and drill 8mm holes as shown in the drawing, then glue and screw them in the four corners.

Step 4: The Legs

Cut the four 30x40 rods in pieces of 85 and 80 cm, then make 8mm holes at 18mm from both ends and round the edges like in the picture.

Step 5: Cutting and Gluing

It's time to make the braced legs. To be sure that they will be perpendicular and with perfect dimensions you can use the same bench plane reinforcement as container.
Place two big washers at each side, between frame and legs, then put in position over the legs one brace 20x40, mark the diagonal ends and cut it. now you have the exact shape for all diagonal braces.
Add glue, press parts together and wait a while, let's say 10-20 minutes.

Step 6: Adding Screws

After that time take it out (it should stay attached) and very carefully drill holes and add screws on each connection. Add also a pair of screws in the centre of the X diagonals, one screw for each side.

Step 7: Drill Side Holes

To drill side holes, where the moving part of legs will be fastened, I suggest to make a mold. It made my job faster and more precise, especially because holes in the mold are well perpendicular, drilled with column drill, and they'll help me to make straight holes by hand.

Step 8: Connect Parts

Almost completed. Insert bolts, place big washers between wood bars and small washers before the self-locking nuts. Check that legs stay well closed adjacent the frame.

Step 9: Try Them All

If everything fits you can paint the work benches as you wish, I painted the surface white and left legs unpainted.
As you see in last drawings, changing connection holes makes possible to vary geometry and style, and the table change height from about 77 to 82 cm. If you wish you can test new geometries adding more holes.

Step 10: 3d Drawings

I took some screenshots from my 3d model so that you can have a better view of different geometries.
I hope some of you makers will find this project useful to build new workbenches.