Hello Anthony and Geoff
Thanks for your reponses and the useful links.
I have downloaded the Selden info and bought a Loos type B .
Deciding what was vertical for the mast was tricky , I was told to use the main halyard cleated and measure to each side but this was not practical as either the Halyard is stretching or the mast is bending according to the force put on it. So I ended up with the gross assumption that the shrouds were the same length, so using caliphers between the ends of the bottlescrews we equalised the lengths to within 0.2mm,well below any tolerances used to make the shrouds I think. Then we wound up the bottlescews to the tension recomended , an unpleasant feeling really, waiting for something to go bang. Use of the Loos guage is interesting looks like plenty of scope for error and wear on the gauge, anyway we have some consistent figures and the mast appears upright so we will have to see how she goes.
Jan
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