Any metalurgical engineers here?

For issues which concern all or several type of DFs and which DO NOT fit into any category below!
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Joined: Tue 26 Aug 08, 23:10
Your Country: USA, North East

Any metalurgical engineers here?

Post by Oscar »

I think like all DF's, LK IV has a rotating mast. There's a big ass pin with a rounded tip that comes out of the bottom of the mast which rides in a SS mast foot......

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There's also some sheaves (removed) that sit right under the mast where 4 halyards come out and are directed sideways. As you can see it's all bent up. I believe it is too small to deal with all the forces. Additionally, the small footprint translated all these forces to the cabin top, which is balsa core, and had a small piece of wood to reinforce it under the mast foot. Then the compression post inside was not quite under the whole contraption.

So, forces too big, water intrusion boogering up the laminate, compression post offset..... yup. The whole thing started coming through the roof. Soooooo, the PO's beefed it all up with a 2x8....... This art work has now been removed and replaced with a nice mahogany knee brace, glassed on to the compression post. (Pic later)

The roof has been opened up in the affected area and the core removed, now being glassed in solid with a large base for the mast foot.

I want to change the design. Bring the halyards out of the side of the mast, straighten out the mast base, and then bolt it to a stainless plate with edges 45º up with holes to put blocks in. Not just for halyards, but also the cunningham, outhaul, and reefing lines. Better mechanics, better load distribution.

Now to the question...... I have some 1/4" stainless and will cut it to shape, then heat and fold the edges. (Have acetylene). BUT, cooling.........slow or fast? (Water) been reading about hardening, annealing etc etc and can't figger it quite out.....
1990 Dragonfly 25 USA-54
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