What would happen to initial stability if you took a double chined
stitch & glue dinghy design and rounded it off so that it could be built
with cedar strips?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Not much, but why not start with a round-bottom boat from the outset? What
kind of boat are you contemplating?

Glenn Ashmore wrote:

What would happen to initial stability if you took a double chined
stitch & glue dinghy design and rounded it off so that it could be built
with cedar strips?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Glenn Ashmore wrote:

What would happen to initial stability if you took a double chined
stitch & glue dinghy design and rounded it off so that it could be
built with cedar strips?

Why round it off at all. You can build hard chine designs with cedar
strips; I've seen it done on kayaks. You start with strips at the sheer,
chines and keel (essentially outlining the panels), then fill them in.

--
Regards

Brian

What got me thinking was an article in GOB about building a Gerr nesting
dink in cedar strip. It gave a basic dink a really classy look. The
builder took the basic proportions of the Gerr and changed it to a sort
of radius chined design. He also gave the bottom a bit of deadrise. I
really like the rowing characteristics of my Gerr dinghy but it is a
little tippy for loading and unloading off a transom. I was wondering
if these changes would make it worse.


Jim Conlin wrote:
Not much, but why not start with a round-bottom boat from the outset? What
kind of boat are you contemplating?

Glenn Ashmore wrote:

What would happen to initial stability if you took a double chined
stitch & glue dinghy design and rounded it off so that it could be built
with cedar strips?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

You would have a lot more work and get a choppy pattern that way because
four times as many strips would have to be tapered to fit. Tapering and
fitting the shorter strips is more than half the work in building a
stripper. If it is not done very carefully you end up having to fill
with a lot of epoxy/filler. Even using wood flour the fill is pretty
noticable.

Brian Nystrom wrote:

Why round it off at all. You can build hard chine designs with cedar
strips; I've seen it done on kayaks. You start with strips at the sheer,
chines and keel (essentially outlining the panels), then fill them in.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

I doubt it will make any difference until the boat reaches some speed
where the round surface will have less hull turbulance and be faster than
the chined version and that's probably not a consideration in a yacht tender.

I did a model of such a conversion, chosing a constant radius of
curvature for each chine I was rounding off. There's a small photo of the
"before" and "after" sections at www.ncf.ca/~ag384/T12.htm or it can be got
to via my home page under "boats".

Glenn Ashmore ) writes:
What got me thinking was an article in GOB about building a Gerr nesting
dink in cedar strip. It gave a basic dink a really classy look. The
builder took the basic proportions of the Gerr and changed it to a sort
of radius chined design. He also gave the bottom a bit of deadrise. I
really like the rowing characteristics of my Gerr dinghy but it is a
little tippy for loading and unloading off a transom. I was wondering
if these changes would make it worse.


Jim Conlin wrote:
Not much, but why not start with a round-bottom boat from the outset? What
kind of boat are you contemplating?

Glenn Ashmore wrote:

What would happen to initial stability if you took a double chined
stitch & glue dinghy design and rounded it off so that it could be built
with cedar strips?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com



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Glenn Ashmore wrote in message news:QQkpb.133837$sp2.21083@lakeread04...
What would happen to initial stability if you took a double chined
stitch & glue dinghy design and rounded it off so that it could be built
with cedar strips?

Well, in racing car terms, it could get a little "looser". It would
probably gain some stability and reach "through" the bouyancy graph
smoother. Rounding it off would give you more displacement and could
offset any tracking and steering that may have been figured into the
harder chines. I think if you want a round hull boat, find and or
design, or have designed, one for you.
Nothing worse than a tool that does not work... 'specially if you put
a lot of time into it.
Scotty from SmallBoats.com... and we can let the jokes go for
now, thank you very much!

Glenn Ashmore wrote:

You would have a lot more work and get a choppy pattern that way
because four times as many strips would have to be tapered to fit.
Tapering and fitting the shorter strips is more than half the work in
building a stripper. If it is not done very carefully you end up
having to fill with a lot of epoxy/filler. Even using wood flour the
fill is pretty noticable.

Granted, but if you want a hard chine boat, that's one way to do it.

--
Regards

Brian

Glenn Ashmore wrote:

What would happen to initial stability if you took a double chined
stitch & glue dinghy design and rounded it off so that it could be built
with cedar strips?

Getting down to the dinghy? You might be interested in my solution, but if
you're talking about nesting dinks then you probably want something that
will take up less deck space than what I'm working on.

Rounding off the chines will knock initial stability down. But you can lose
a little weight and drag, too.

I had to design my own dinghy from scratch, it's hard to believe but I could
not find a set of lines I liked for initial stability & good rowing
characteristics. After a lot of study of small boat hull shape, I think it's
close enough to right that we are going to gamble a chunk of money on
building it in carbon fiber. And it's going to be really really pretty.

Fresh Breezes- Doug King