Swiebertje,
Can you help me in return?
When you say (what point on the mast we use for THIS measurement)
What is This?
When I was talking about mast pre bend, it was the measurement at spreader brecket height taken from the main halyard to the rear face of the mast. ie 40 mm /4mm or any other?
If your talking about the spreader length, i take it from the shoud wire to the nearest side of the mast, ie shortest distance.
Any Help ?
CP 😕