The 2' x 4' metal sheet for the top of the board was purchased from Lowes Lumber, which I mounted on top of a 3/4 plywood sheet, also from Lowes.
Magnets were purchased from Amazon - Master Magnetics CA41LWHX100 Ferrite Magnet/Low Carbon Steel Magnet Fastener, Rectangular with Center Hole Zinc Plated, 1" Length, 0.813" Width, 0.313" Height, 12 lb. (Pack of 100).
Make a template from 1/4" ply with all the hole positions established to then lay out and mark all your other fixtures. Clamp down arms are hardwood, and the thumbscrews I found at Lanier Hardware in Lexington
I used 10x24 bolts to hold the magnets at the bottom of the fixtures, and 6x32 bolts for the clamp down arms on the tall fixtures on previous page.
NO holes in your plans or build board
The four different Fixtures. 1/4 Plywood Fixtures and Hardwood arms.
When not in use the extra pieces can go on the wall.
The Results: A scratch built 1935 Aeronca C-3.
Six foot wingspan and powered by an OS .35 2-cycle.
These are the instructions for the tall fixtures
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