Building a Vacuum Forming Table

The dimensions provided below will give you a place to start with the cornering and joining of your rack boards but length will ultimatly depend on the size of your vacuum box and its table top whos size depends directly on the size of cookign sheed used for its construction.

Building the Rack

	The rack is formed by four boards each of which are trimmed to leave a one inch stub to connect it with two other boards in the rack. A metal L-bracket and 4 wood screws hold each of the corner boards together.

The rack is composed of two pieces which bolt together to hold the plastic sheeting. Building the vacuum box as I have described will result in the table top protruding from the box itself. The inside edges of the bottom rack are recessed to accomodate this protrustion.

	Dimensions of the rack boards are shown left. For my vacuum table the bottom rack boards had a rolled area with B, and C equal to one inch and A equal to 1.5 inches.

		The hardware used in to lock the frames together is pictured left. A 2.5in X 0.25in bold is recessed into the bottom frame. For added strength a recessed threaded 0.25in well has been fitted into that frame. The top fram has been drilled to allow the bolt to pass though it and be secured by a 0.25in washer and wingnut.
		Bolt placement in the bottom rack is shown left. Ten bolts are used to lock the frames together. the outer bolts on each board were placed 2.5in from the edge of the boards.
		To recess the metal wells a hole for the well shaft was first drilled all the way through the board. Then a hole with a larger diameter then the well was drilled part way into the board. The well has metal prongs on it which are designed to be pressed into the wood arround the well. The well was then placed in the guide hole and wodded blocks and a vice were used to press the well flush with the rack surface. The unused hole area arround the well was then filled with putty and sanded.
		On the side of the bottom rack piece opposite the metal wells a hole wider then the shaft of the bolt has been drilled to fully acomodate the head of the bolt. When finished the rack top mates with the base through the 10 connecting bolts and is held in place by wing nuts.
		In order to provide a seal betweene the rack and the table top and a high traction surface betweene the racks and the plastic I used strips of silicon sheeting tacked down to the frame.
		To obtain the sheeting I used a silicon baking mat cut to produce an o-ring for the bottom rack and a series of one inch wide strips to cover the inter rack surfaces.