Hi Dave, well these types of trestles have been used for donkey’s years, Builders Trestles by builders, and others, and myself, and I’ve not, and I don’t know anybody else who have used this type, for them to have encountered or tendency for them to fold and collapse as you have shown, plus the ones shown, would have to shear off eight bots which are holding the corner posts onto the trestles.
Regards Nick.
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