It may be possible in theory to reuse the head tube and the rear triangle of a old donor frame, just welding in new top and down tubes. Some straight guage, heavier wall tubing would be stronger than bicycle tubing.
But it may be cost prohibitive
@PhilDAS started
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It may be possible in theory to reuse the head tube and the rear triangle of a old donor frame, just welding in new top and down tubes. Some straight guage, heavier wall tubing would be stronger than bicycle tubing.
But it may be cost prohibitive