Sorry, but without any data about wall thickness , the sort of alloy used, or a column with calculated breaking (or yield) strength (moment), that file is of little help.

Arne

PS: I also miss a column where the weight of the masts can be written.

Roger, if your boat has grown to 6 tons (metric) then she is in the Tystie class or there about. 12600kpm wooden mast wold be equal to a diameter of 31cm (with 20% wall thickness)! Sounds like a heavy schwein to me. I try to keep the weight of my spruce masts not over 3% of the displacement of the boat. In that  case the mast should not be over 180kg.

Arne

PS: I have lost track of where that mast database is. It would be interesting to have a closer look at Tystie and her rig.

Maybe the numbers are based the boat carrying a greater load than I do. In the paperwork there is a list of materials that the previous owner proposed to carry and total displacement came to about 6.5 tonnes.

Hi Arne,

Yes, when I  first got Shoestring, I understood that 160 degrees is the capsize point and that when empty, the righting point is about 130 degrees.

I am not at all familiar with these calculations and figures and I hope I was reading the drawing correctly. I have  however uploaded a jpeg of the curve  to illustrations. Perhaps you could double check?

Appreciated!

Roger