Re: [bolger] isometric of Bolger 15'6" ft cartoon Modern Sandbagger cat boat

Further to the mention of Red Zinger, I believe he said the bilge was to be strip planked.  I wonder how the transition from strip to ply might be accomplished at the sheer panel?  My guess would be to run the strips up to a ribband and then mill the seam to match the ply edge.

On 10/4/2010 5:31 PM, Christopher C. Wetherill wrote:
He said something similar in Red Zinger chapter of BwaOM.  The plumb stem is what I noticed.  Is there a place where I might read this article?

On 10/4/2010 5:21 PM, Bruce Hallman wrote:
Good eye, yes, PCB discusses the twist in the forward 3 feet of the
bilge panels.  He suggests:

"The hull shape is meant for sheet plywood, except that the forward
bilges can't be planked with sheets for they would not take the twist
onto the plumb stem..."
__._
Hopefully, someone can do better than I with "traditional Mallorciun fishing boats". Instead of 'Mallorciun' could it be 'Mallorcan'? Perhaps at a stretch "Menorcan"? My grasp of either Spanish or Catalan is very poor. If it is a boat type from the Balearic Islands then...

Mallorca, Menorca. The type a Llaüt, or Llagut? Nice boats.

Side seating and hatches approximating SBJ Cartoon #? more evident in the first few items:

Llaüt
http://www.barques.net/llautsfusta.htm
http://theinvisibleworkshop.blogspot.com/2008/04/el-llaut.html
http://thumb15.shutterstock.com.edgesuite.net/display_pic_with_logo/5058/5058,1128759689,4/stock-photo-single-wooden-white-fishing-boat-port-cala-bona-mallorca-majorca-spain-609737.jpg
http://commons.wikimedia.org/wiki/File:Lla%C3%BCts-Es_Portitxol.JPG
http://www.flickr.com/search/?q=Lla%c3%bct
http://www.flickr.com/photos/manua1971/3051202734/
http://www.gfornells.com/en/fornells.html
http://1.bp.blogspot.com/_rsInhL8uv34/SMzG1DeeadI/AAAAAAAAAEU/fLH9SHxpOS0/s400/P1014319.JPG

Llagut
(seems more likely to be rowed, to be open, with rowing thwarts, elongated?)
http://www.flickr.com/search/?q=Llagut
Majorcanhttp://www.consorcielfar.org/_imagenes/TEXTO/94/3575_1.JPG
http://image56.webshots.com/56/0/60/55/2865060550053767781vBouXE_fs.jpg
modelshttp://velaivent.net/maquette.htm
http://www.modelismonaval.com/magazine/barcascatalanas/galeria2.html
http://www.modelismonaval.com/magazine/barcascatalanas/galeria2.html


--- Inbolger@yahoogroups.com, Bruce Hallman <hallman@...> wrote:
>
> Hoping to swing the conversation back in a positive direction, here for
> discussion is an isometric of the Bolger cartoon "Modern Sandbagger" from an
> old Small Boat Journal (Jun/Jul1990, vol 73) article. Billed as "family
> fun", speed and comfort. It was intended to be tented over, with sleeping
> in fabric cots. The hinged hatches are patterned after traditional
> Mallorciun fishing boats, intended to give easy live weight for sailing
> stability, with the lee hatches dogged tight giving lots of reserved
> buoyancy in a knockdown. 229sf of sail area on 15'6" of hull length.
>
>http://www.hallman.org/bolger/Sandbagger/
>

--- Inbolger@yahoogroups.com, Bruce Hallman <hallman@...> wrote:
>
> > Very nice. Looks like a bit too much twist at the stem for plywood. Any chance of a view in "Gaussian curvature" mode? Did the article suggest a construction method?
> >
>
> Good eye, yes, PCB discusses the twist in the forward 3 feet of the
> bilge panels. He suggests:
>
> "The hull shape is meant for sheet plywood, except that the forward
> bilges can't be planked with sheets for they would not take the twist
> onto the plumb stem. Other boats in which I've used this shape had
> the bilges cold-molded, or double-diagonal planked, but I think the
> foremost sheets could simply be cut into narrow planks and the seams
> taped, holding the shape with transverse frames."
>
> "The slightly concave sections flaring to the full chine carry the bow
> high as the boat heels or cuts through the wave crests. She seems to
> ride on the lee bow wave. A boat with a sharper deck line will go
> faster as long as she is sailed upright, but this bow is more
> forgiving, and the added deck space is convenient."
>
My eye is not good enough to see whether the curve from bow to stern is the same for the bottom and bilge planks or not quite. Given all that curve, how would it affect planing? Surely a boat with this much sail area will plane. Practically fly I expect. My goodness what fun, but tacking, and worse jibing, would take a deft touch.
Eric

--- Inbolger@yahoogroups.com, Bruce Hallman <hallman@...> wrote:
>
> Hoping to swing the conversation back in a positive direction, here for
> discussion is an isometric of the Bolger cartoon "Modern Sandbagger" from an
> old Small Boat Journal (Jun/Jul1990, vol 73) article. Billed as "family
> fun", speed and comfort. It was intended to be tented over, with sleeping
> in fabric cots. The hinged hatches are patterned after traditional
> Mallorciun fishing boats, intended to give easy live weight for sailing
> stability, with the lee hatches dogged tight giving lots of reserved
> buoyancy in a knockdown. 229sf of sail area on 15'6" of hull length.
>
>http://www.hallman.org/bolger/Sandbagger/
>
He said something similar in Red Zinger chapter of BwaOM.  The plumb stem is what I noticed.  Is there a place where I might read this article?

On 10/4/2010 5:21 PM, Bruce Hallman wrote:
Good eye, yes, PCB discusses the twist in the forward 3 feet of the
bilge panels.  He suggests:

"The hull shape is meant for sheet plywood, except that the forward
bilges can't be planked with sheets for they would not take the twist
onto the plumb stem..."
> Very nice.  Looks like a bit too much twist at the stem for plywood.  Any chance of a view in "Gaussian curvature" mode?  Did the article suggest a construction method?
>

Good eye, yes, PCB discusses the twist in the forward 3 feet of the
bilge panels. He suggests:

"The hull shape is meant for sheet plywood, except that the forward
bilges can't be planked with sheets for they would not take the twist
onto the plumb stem. Other boats in which I've used this shape had
the bilges cold-molded, or double-diagonal planked, but I think the
foremost sheets could simply be cut into narrow planks and the seams
taped, holding the shape with transverse frames."

"The slightly concave sections flaring to the full chine carry the bow
high as the boat heels or cuts through the wave crests. She seems to
ride on the lee bow wave. A boat with a sharper deck line will go
faster as long as she is sailed upright, but this bow is more
forgiving, and the added deck space is convenient."
Very nice.  Looks like a bit too much twist at the stem for plywood.  Any chance of a view in "Gaussian curvature" mode?  Did the article suggest a construction method?

V/R
Chris

On 10/4/2010 4:45 PM, Bruce Hallman wrote:
Hoping to swing the conversation back in a positive direction, here for discussion is an isometric of the Bolger cartoon "Modern Sandbagger" from an old Small Boat Journal (Jun/Jul1990, vol 73) article.  Billed as "family fun", speed and comfort.  It was intended to be tented over, with sleeping in fabric cots.  The hinged hatches are patterned after traditional Mallorciun fishing boats, intended to give easy live weight for sailing stability, with the lee hatches dogged tight giving lots of reserved buoyancy in a knockdown. 229sf of sail area on 15'6" of hull length.

http://www.hallman.org/bolger/Sandbagger/




Hoping to swing the conversation back in a positive direction, here for discussion is an isometric of the Bolger cartoon "Modern Sandbagger" from an old Small Boat Journal (Jun/Jul1990, vol 73) article.  Billed as "family fun", speed and comfort.  It was intended to be tented over, with sleeping in fabric cots.  The hinged hatches are patterned after traditional Mallorciun fishing boats, intended to give easy live weight for sailing stability, with the lee hatches dogged tight giving lots of reserved buoyancy in a knockdown. 229sf of sail area on 15'6" of hull length.

http://www.hallman.org/bolger/Sandbagger/