Pete Rasmussen wrote:..
Here's a link to Michael Kasten's great article on stability...http://www.kastenmarine.com/beam_vs_ballast.htm

Nice article, like his Vahalla design..

Conor O'Brien hoisted an anchor aloft on Saoirse, on his circumnavigation and reported a great - and improved - difference in motion.

Thanks Brian.
I've just hauled 20 kg of lead along the inner forestay by the staysail halyard to see what effect this has on the yachts motion.  Definitely a hard hat area now!!

 Maybe I should have chosen "Stability" as my subject Kurt.  Once knocked down with the mast in the water maybe we are in the hands of the Gods. Will it fill with water?  Will it break?  
Still better not to get knocked down in the first place.  According to the above mentioned tank tests a wave around 35% of the hull length can turn her over if beam on to the seas.  a heavier mast may just make it slightly less likely to get rolled but I doubt its a really significant thing but just going in the right way, so to say.
The effect of weight on the motion will be the most significant effect that will be lived with day in day out and that's what I'm excited about most.  
I've already spent a lot of time getting the old girl up to speed and she's still my ideal type so if I can cure her of the uncomfortable motion it would be a real boon.  When I bought her I remember saying to the seller "   slow but comfortable this type" and he said "not too slow" and avoided the comfortable element and I see why now.  She can get an attrocious motion in a short steep beam sea, even at anchor.  Not a comfortable yacht at all.  I'm thinking she was designed with a solid timber mast and someone thought to make her more sporty and modern with an aluminium mast.
I changed the halyards from 12mm to 8mm line and we could feel the difference so I think a bit more weight will be felt quite markedly.

Pete, I have a mast that I designed for another project that did not come off.

Dia at partners 245mm, wall 4mm, bury 2 300mm, LAP 18 000, Dia at masthead 100mm, 16 sided and it's hot dipped galvanized.

It's longer than you need and was originally going to be a mast for a large gaff cutter. It could easily be cut down and would weigh in at around 300kgs once that is done.

It's more than strong enough for you. I'd stay away from stainless for masts. It has the same fatigue problems as aluminum plus other of it's own.

BTW I just looked up the design, being originally for a gaff rig, the lower part is parrel sided and only the top 6 620mm is tapered. That could work well for you, you'd have a parrel sided length of about 4 000mm and then the tapered section of 6 620. The bury is also tapered from dia, 245 at the partners to dia 150 mm at the base.

If you are interested, please contact me directly and we can work something out.