Subject: [harryproa] Re: Materials list, Price!!!!
From: Mike Crawford
Date: 3/2/2006, 11:42 PM

  I believe there are a number of folks who would like to try tortured ply, cylinder moulding, and KSS construction, but aren't sure about how to replicate some of the compound curves found on the harryproas.

  If money were no object, and I were paying a yard to build the boat, I'd go with strip-planked kiri.  Although it would have some extra weight over corecell, I'd enjoy the peace of mind that comes from having a solid structure even before the glass and resin are added.

  On the other hand, if I had to build the hulls myself, I'd be sorely tempted by the speed of the other construction techniques.  Provided I was aware of a way to get those nice compound curves found on the topsides of harryrpoa hulls, of course.

  Any light you can shed on this issue would definitely be appreciated.

  Congratulations on your proas, by the way.  Is there a place where we can learn more about them?

       - Mike

jerry freedomev wrote:
               Hi Robert and All,
                    I'd think a HarryProa wuld be easily built in tortured ply technic for much less money, labor, weight. Any reason why it wasn't used?
                    In it I've built a 28' proa with the room of a much larger Harry for under $2,000 in materials. And a much larger 36" Proa in about $3,000.
                                           Jerry Dycus  

Robert <> wrote:
From my own minimal experience, it is more important to get
reasonably accurate dimensions rather than finish as you are going to
sand a lot of it away. If you are cutting the planks yourself you can
get three different widths according to curvature and make the
chamfered edge at the same time. If you really want to be fancy, you
can glue all the strips to full length and taper and chamfer them
before you start and almost completely avoid cheaters.
Techniques for using polyprop honeycomb are on the nidacore site. It
is worth while looking at the impact testing of polyprop honeycomb
sandwic compared with balsa core. A great lump of RSJ was hoisted up
to the heoght of the shed roof and dropped onto the sandwiches. The
polycore caused the RSJ to bouce up into the air without damage while
the balsa fore fractured. I believe, though I haven't tried it with
polycore that a hot iron can put creases  into the face of one side
to control bending and also to provide resin channels for resin
infusion. I think it well worth using vacuum bagging to reduce weight
and impove adhesion for high stress areas but at a price of extra
consumables and effort but I am in two minds about infusion.
The difference in price is not worth hassling over. I'd be tempted to
use poulonia in the high stress areas to save on glass and polycore
in the flat, low stress areas to save on time and weight is a good website to check

congratulations about having suport from your boss for the project.
Good luck wit the finances.
--- In, David Howie <dana-tenacity@u...>
> Part of the problem is to know whether you are comparing apples with
> orangutans. That price for paulonia is raw planks, need to be
dressed and cut.
> Don't know whether the planks are to be cambered on the edges. Poly
> fascinating, lots of unanswered questions, how does anything bond
to it? can
> an amateur work it successfully.
> Speaking of amateur I started off thinking I knew something about
this boat
> stuff, but the deeper I dig the less I know.
> Pity there isn't somebody else nearby who was thinking of building
a Harry.
> Trying to talk my wife into a trip to Aus when Bain's boat hits the
> (presumptive of me isn't it?), she doesn't think much of Aus, but
she has
> given the project the green light if the funding happens.
> ------ Original Message ------
> Received: Wed, 01 Mar 2006 06:26:30 PM MST
> From: "Robert" <cateran1949@y...>
> To:
> Subject: [harryproa] Re: Materials list
> I couldn't get near that price for Poulonia. Suspect rob can get
> better prices on glass and carbon. Probably worth the freight. May
> to wait on carbon till the shortage is overcome and prices
> manufacturing costs rather than scarcity. Can you give areas of
> materials to allow comparisons?
> My calculations for polycore are with no ply, larger cockpit/saloon
> a cockpit cover like Bain's.
> Overall calculations are not that different. I get in the order of
> sailaway with schooner rig, including consumables. only $10k for
> boat materials.
> Regards,
> Robert
> --- In, "oceanplodder2003" <dana-
> tenacity@u...> wrote:
> >
> > OK it's in files now.
> > >
> >

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