It's not really important, but I am curious if this old thing really is over 40 years old. The ribs have numbers stamped on them, rather than printed, sort of "dot matrix" stamping. Also, the spars appear to be cut to size with a circular saw, rather than sanded or sliced to size. The horiz stab also has circular saw marks on it, could be disc sanding marks, but since it's not tapered, I think the sheet stock the tail feathers were cut from were sliced from thicker stock using a table saw or something similar.
Anyone have any idea when these practices were stopped? Or if there's any other way to tell how old it is?
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