OK. It has been two years since I made this so I'm going to publish what I have. It's not rocket science.
What I wanted
Spin Art table durable enough to be used at an annual fair.
Short enough to be used by very young children.
Small enough to be stored taking up a minimum of space.
Cost next to nothing. I used junk lumber from my garage.
Power drill / screwgun.
Spade bits. 1 = shaft diameter of arbor, 1 = diameter of arbor washer
Saw - I used a circular saw with speed square for accurate cuts. A table saw would be even better if you have one.
Various screws depending on how you attach the apron. Wallboard screws are adequate.
Old window fan
Arbor to fit your fan motor shaft
1 X 4 (or 2 X 4) for apron
1/2" or thicker plywood for table top
2 X 2 (I used 6') for legs and mortises
Wood chisel to create recess for fan switch. Moving the switch is optional (maybe even totally unnecessary).
Chisel, plane, sand paper or file to taper legs to better fit into mortises.
Drill bit / countersink for screws attaching turntable surface.
Step 1: Table Top
Table top is 3/4" plywood scrap. The piece I had was already dead-on square so I adopted it as the size for my table. Any size that accomodates your fan is good - extra space to hold supplies is even better.
I made my apron so that I had a lip equal to the thickness of one of my boards. That way I could use cut off scraps to align the apron. Dimensions are not that critical but be sure that opposite sides are of equal length and that your cuts are square.
I used pocket screws to attach the apron but iron angles or screws through the table top would work well enough.
Step 2: Knock Down Legs
I didn't really have the hardware or the know-how to make a sturdy folding leg so I opted for quickie mortises to receive the legs. I made another set to hold the legs flat under the table for storage and transport. I clamped everything down as shown in the first picture and used screws and pocket screws to secure the pieces.
One of the legs didn't fit so snugly so I put in pivoting blocks to keep legs in the storage mortises.
Step 3: Turntable
The turntable is 8 1/2" X 8 1/2" masonite. These dimensions will take a standard letter paper with enough overage on two sides to fold over and tape to the bottom.
I drilled the masonite separately from the supporting block of wood and then used the spade bit to align the two. If I had to do it again I would probably attach the two pieces first and just drill one hole.
Once I had the turntable finished I attached the fan to the table top using the holes and screws that previously secured the protective screen.
Step 4: Follow Up
81/2 turntable perfect for letter size sheets of paper. Fold the excess and hold in place with painter's tape while spinning and then tape to wall while drying. (Write kids' names in the margin or you'll be sorry - trust me.)
Some lawn mower wheels at one end could have turned this into a sort of hand truck to carry my box of paper and paints. Maybe someday.