Subject: Re: [harryproa] Re: Can you cut a carbon mast in half, then repair it? |
From: Rob Denney |
Date: 4/29/2009, 11:01 AM |
To: harryproa@yahoogroups.com.au |
Reply-to: harryproa@yahoogroups.com.au |
Still a theory, but there are 3 owners considering using them.
Rob,so what is the progress on the telescoping masts,was there any build yet?...or is it still just a theory?
Regards
--- In harryproa@yahoogroups.com.au , Rob Denney <harryproa@...> wrote:
>
> G'day,
>
> Definitely doable. Not sure which wil be the first boat to use it, but
> there are 3 thinking seriously about it.
>
> Gardner. Built it in one piece and if you ever shipo the boat, cut it in
> two and rejoin it using the same laminate as the mast on the outside of the
> join with a n overlap of at least 100 times the mast wall thickness plus
> tapering the laminate. Not optimal, and may mess a little with the bend
> characteristics, but won't break.
>
> Certainly try the other rigs, it would be good to see how they worked and
> costed compared to the standard rig.
>
> regards,
>
> Rob
>> On Wed, Apr 29, 2009 at 8:55 PM, proadude <rbmaui@...> wrote:> > --- In harryproa@yahoogrou
>
> >
> >
> > Hi All,I was away for a while...a long while,but I just got back and in to
> > a very interesting subject-a two part mast!?...or,what Rob was talking about
> > before,the telescoping mast!!I wonder what has happened to this idea,and I
> > do think that this is the answer for the future free standing mast for the
> > proa,and not only proa boats...so,what is the progress in this area Rob?Is
> > it "doable?
> > Regards
> >
> >ps.com.au <harryproa%40yahoogroups.com.au >, Mike
> > Crawford <jmichael@> wrote:
> > >
> > >
> > > A two-pat mast seems to be the best bet.
> > >
> > > A telescoping mast would also be a great fit, but that's a more
> > > complex design, and you would lost anti-turtle flotation in one half the
> > > mast. I do believe that a telescoping mast could be done, but I also
> > > wouldn't want to be one of the early adopters.
> > >
> > > Robert's idea of a gunter would certainly work. However, I'd
> > > personally rather have a rig that makes it easy to raise and stow the
> > > sails in any wind, either with roller-reefing or using slides/cars and
> > > lazy jacks. It would probably be more time-consuming to go from sail
> > > cover to gunter and back again, especially if single-handed.
> > >
> > > I'd have a pro design a two-part mast, though. There is some serious
> > > stress in an unstayed rig, and while it's easy to design for, it does
> > > have to be designed for. A joint introduces other stresses, so I'd want
> > > it designed by a professional who has access to good Finite Element
> > > Analysis software.
> > >
> > > Cutting a mast and rejoining it could be done, but it probably
> > > wouldn't be pretty, and more importantly, you'd lose the ability to pass
> > > stress through nice, long, continuous carbon fibers. That said, if the
> > > patch were thick enough and long enough, it could work. I'd still want
> > > someone to do FEA, though, to make sure how long and thick the patch
> > > would have to be.
> > >
> > > - Mike
> > > / /
> > >
> > > Gardner Pomper wrote:
> > > >
> > > >
> > > > Hi,
> > > >
> > > > Still trying to figure a good rig for a boat that wants alot of sail
> > > > area (Rare Bird-ish), but can still be shipping in a container. The 2
> > > > part masts sound doable, but difficult. I was wondering if it makes
> > > > sense to just build a regular 1 part mast, 50-60 feet long, then cut
> > > > it in half, if I do end up shipping the boat in a container. It will
> > > > cost at least $6000 to ship the boat, so I can't imagine doing it more
> > > > than 2-3 times in my life (who knows, maybe I never will). Does it
> > > > make sense to just cut the mast, stick it in the container and then
> > > > repair it at the destination?
> > > >
> > > > Thanks,
> > > > - Gardner
> > > >
> > > >
> > >
> >
> >
> >
>