Build Work Table

Materials List:

• 2 @ 2" x 6" x 12' lumber #2 or better  long side stretchers
• 2 @ 2" x 6" x 8' lumber #2 or better    end & middle cross support rails
• 4 @ 2" x 4" x 8' lumber #2 or better    legs and middle cross support rails
• 2 @ 3/4" x 4' x 8" sheet goods            MDF, particle board or simular (manufactured materials give a more consistent surface than plywood)
• 1# 3" x #10 deck or structural screws   
• wood glue, construction adhesive or simular
• 1 roll 3' x 50' x 4 mil plastic sheet
• 1 quart light color paint (to cover 100 square feet i.e. both side and all edges)
• (I cheated and used 4 Simpson corner ties to keep the outside frame intact while I fitted the cross rails. This is optional.)

My KR2S build table was excessive in terms of effort, weight and structure. I decided this time around to have a bit more foresight and set a few goals up front.

1. This table had to be quick to build (in keeping with Marvin's goal of "Build it, Fly it."
2. I want this table to be something I can live with after the project is completed. 12' x 4' about fills my entire shed so I want to be able to eliminate 1/2 the table when I finish. Cutting through the stretchers, adding a couple more legs and I'll have a couple of 6' x 4' tables. Much easier to manipulate.
3. I wanted a smoother surface than the particle board I used last time. And a single layer 3/4" top should be more than enough; I used 2 @ 3/4" last time.
4. Placing clamps near the edges can be nice. Long enough clamps to use on the edges of the table (all the 6 3/4" from the surface down to the bottom of the rails) are expensive and awkward. The MDF sheet material I bought comes as 49" x 97". I cut 24” off each length, giving me a total 49” x 144” work surface. To gain a 2" clamp-access margin all the way around, my table frame actually measures 45" x 142"

A minimum of tools are required. Chop saw not shown.

I used 2 x 6 x 12' stretcher boards, 2 x 6 x 4' rails on both ends and through the middle. I used 2 x 4 x 4' rails to support the middle sections. I built the supporting framework upside down of course. I pre-drilled, glued and screwed the rails to the first 12' stretcher closest in this photo. Ok, that was excessive. I also marked the position of the rails against the other stretcher.

After I finished the first stretcher and rails I stood it up on to apply more glue and screws. Using the alignment marks I predrilled the other stretcher and started the screws into place.

I then laid it back onto the (relatively flat) floor. I used the top surface cutoffs 2' x 4' with the factory edges as alignment squares to ensure the frame was square.
 

Then I laid the work surface onto the frame. This weight helped make everything lay flat. I drove the screws home with the impact driver. Then I painted the exposed surface and edges. This will become the bottom of the work surface.

After the paint dried, I removed the work surface and alignment squaring sheets. I installed a temporary shear panel to make positive the frame didn't rack out of square. I flipped it over to top-side up, propped the frame up on saw horses and cut 32" legs and installed them to be flush with the top of the rails and stretchers. At this point, I leveled the table with a 4' spirit level. You can see the shim under the right leg in this photo. The far end required 2 strips of cardboard side-to-side and 2 1/8" plywood shims. So far, so good.

I got the work surfaces up on the table, bottom-side coating down.

Another coat of paint so the MDF doesn't absorb moisture and swell up. I let it dry overnight.

Finally, the moment of truth. I forgot who taught me. Use a length of .020 or finer safety wire, fix it on one end, place a solid shim at both extremes and pull it taught. It should sing like a guitar string.

Tap the wire over the entire length. What you are looking for is a consistent travel distance down to the table. You can use AN washers to check for consistent height of the wire. Shortest distance between 2 points is your straight line; high and low points become very evident. Now string the wire for both diagonals and check those lines too.

Install the plastic sheet. I used 3' x 50' x 4mil material with a 10" overlap. Lay it out, stretch it taught with spring clamps, seal the seam with packing tape and staple it into position.

Now, build your airplane!