Rob,

I am not clear on your explanation. It sounds like you make 3 pieces for each mast: a leading edge, a trailing edge and square stub. From your explanation of how you are avoiding joins at the stressed part of the mast, I know that I am misunderstanding. Could you break it down a bit? Are you building the wing mast all out of panels? and how many panels?

- Gardner

Pasadena, MD

On Sun, Feb 6, 2011 at 2:07 AM, Rob Denney <harryproa@gmail.com> wrote:

 

That is one way to build them, but I now build them from a leading and a trailing edge and add the sheer web.    The base of the mast is square section, which gets bogger up to round.  This maximises the distance from the neutral axis, increasing the stiffness/reducing the carbon.  You could do as you say, but this is effectively a join at the most stressed part of the mast, therefore the heaviest and most expensive, as well as the most likely to break.  Easier to put it near the top. 

rob

On Sun, Feb 6, 2011 at 7:43 AM, Gardner Pomper <gardner@networknow.org> wrote:

 

Rob,

I am back with questions about stub masts, because of the problem of fitting a mast in a 40' container. I know you didn't like them, and I remember you mentioning the problems with putting the bearings inside where you could not reach, but I wanted to ask a different question.

When you are building a freestanding wing mast, don't you hve to build the round, rotating part seperately from the wing part and then bond them together? Couldn't you mechanically fasten the stub inside the wing, and leave the bearings down in the hull? Then you could take them apart. I could probably deal with a 40' luff, but going down to 33 or so just doesn't give me enough sail area.

- Gardner

Pasadena, MD