It's a minor project because it's so simple! You can have one working in no time, too!
This How-To is also available at http://benheck.com/phpBB/viewtopic.php?t=18142
It's dirty, looks like dirt, but works absolutely amazingly.
This is largely based off the "Studio Creations" table (see Turbo's Sticky), and is probably redundant, but I'm going to write this anyways. It's also very lengthy.
First is the positive of the shape your plastic will take. This is very straight-forward, and the stickies over at Benheck.com have various methods of performing this task. I used wood. If you have a little patience (and a little clay to touch it up) it is possible to make a wonderful piece of plastic from a wooden mold.
Second is the plastic sheet. I used styrene, although several other plastics such as Acrylic supposedly work great too. The thickness will ultimately be determined by the application. For a portable, don't go lower than .060", or 1.5mm. I bought a big sheet of this, so it is what I will use. .080" (2mm) is probably optimal for a portable, or most other applications. But if you need something a little less stiff, go with .060".
Look how simple it is!
Note the L-bracket's placement. It should be inside or outside of the weather stripping, to minimize air leakage.
The set-up, minus the frame. Notice how the "hose" is allowed to fit underneath the table (It's actually just part of the hose). For someone less fortunate than me, this will be in between two cinder blocks or other item of the supporting kind.
Fifth is the frame.
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