Subject: Re: [harryproa] Re: Trailerable rig questions |
From: Mike Crawford |
Date: 4/8/2009, 10:43 AM |
To: harryproa@yahoogroups.com.au |
Reply-to: harryproa@yahoogroups.com.au |
I hesitate to say I'm going with any boat, because that would imply
action, and that's not likely to happen this year.
If I had to choose, I'd go for a Harry-class boat with the largest
cockpit that will allow it to collapse down to a 12' beam, with the
same shape/design/
Rob has argued that the increase in weight from the scissors design
isn't worth it, especially when you consider that single-piece
demountable beams would be lighter, stronger, and stiffer. Whether or
not he's right is a subjective matter that depends largely upon how
lazy you are, or whether or not you'll have another person to help you
trailer the boat..
Which does call into question how much you want to spend in order to
optimize the boat for trailering. If you don't have to collapse your
beam on the water, single-piece beams will give you a lighter,
stronger, stiffer, and cheaper boat that can have a wider overall beam
than if you go with telescoping beams. More space and righting moment.
The question is how often you need to trailer. If it's only once or
twice per year, and you don't need to collapse on the water, maybe the
expense of going with a telescoping system isn't worth it. You could
rig up a custom trailer with some cradles/dollies that could allow you
to get the boat onto a trailer in an hour or two with one or two
people. The scheme of using a stub mast to hoist the main mast up by
its center of gravity is one that could probably be used by a single
person as long as it's not windy.
Going with a less fancy design might be slightly less convenient, but
perhaps the time penalty is not that bad, especially given the
performance benefits.
So, back to the Contrarry, eh? It's all a matter of perspective.
Instead of being a cramped liveaboard, it's actually a luxurious camp
cruiser.
- Mike
Gardner Pomper wrote:
So which harry are you going with?
This boat started out as a copy of sidecar, adjusted a displacement to
handle a fat guy. I figured I could build that. It kinda grew as it
turned out bigger and heavier than I expected, up to the point where
it is again in the "Contrarry" class of boat.
I wanted it to remain trailerable, but I am going to have to start
specifically looking at what that is costing me, because price is
probably the primary motivator (well, that and ease of construction)
I currently have these complications because of my trailerability
requirement:
1) beam limited to 16' (maybe ok)
2) telescoping beams, which means I have a total of 6 beam sections
3) mast height limitations, since I need to be able to unstep it by
hand (by myself) and fit in on the trailer
4) boom length limitations, due to reasons 1 & 3, as I posted in the
first message of the thread
I really need a way of seeing what this trailerability is costing me.
I will very rarely trailer it. Collapsing it to fit into a slip would
be nice, but would still require the complex beams. If I could figure
out how to calculate the beam and rig costs, for trailerable and not,
I could make a rational decision. It would be nice to at least be able
to replace the beams later if I decide to do it. Start with fixed
beams, with the option to convert later if I really need it.
With the materials for the hulls only costing $10K, I don't want to
spend another $10K (or more) on teh beams and rig.
I have been thinking about rocker, and will have to ask Rob when he
gets back. The way I am planning on building, I only have the U shaped
hull for the middle 50% of the boat. The fore and aft 25%, I was just
planning on using solid polystyrene foam for the keel section (about
6-8"), which would be hand shaped, so it would be easy to make that
with some rocker.
Hopefully I can get enough sorted out to start building this summer.
- Gardner