Today, I built the basic box for the downdraft table. I screwed it together dry (no glue), which should make it air tight enough for this purpose. I have seen plans for these sorts of tables that call for sealing the seams and all that, but I doubt that all of the leakage along these seams will amount to a fraction of the air that goes through one of the holes I will put in the top. It just doesn't matter that much, so I won't seal it.
I clamped all the parts together for a dry fit, and clamped it into the vise.
Clamped Together for a Dry Fit
Then, I marked the locations for the screws that will hold it together.
The Locations for the Screws are Marked
To speed up the marking of the screw holes, I jammed a pencil into the hole of my marking gauge and set it to 3/8".
This Will Mark 3/8" Into the Wood
Since the 1" pine is actually 3/4" thick, the 3/8" mark will position the screw into the middle of the edge.
I did not post a bunch of tedious photos about screwing the box together. You have seen that all before. Using my regular #8 - 1 1/2" screws, I screwed all the parts together. As you can see in the photo below, the lid fits tightly inside of the box.
The Lid Is Being Held Up By Friction
The lid fits tightly enough that it will stand up on its own simply from the friction of the tight fit. Here are some close up shots of the ends where the lid has been jammed.
One End
The Other End
The fit is tight enough that it will even stand upright if I push it all the way down into the box.
At Attention
The tightness is good for getting a tight seal, but I want to make it very slightly less tight for ease of inserting and removing it from the box. But that will have to wait for next time.