Small trimarans under 20'

Corley · Dec 22, 2016

It has its moments and some areas of deep water and the main shipping channels are dredged but it's a bit like Westernport Bay it looks like paradise on a sunny day when the tide is up but paradise can look mighty short on water at low tide.

gypsy28 · Dec 23, 2016

I sail my Hobie 16 on Moreton Bay all the time and my rudders know all about the sand bars (not to mention the turtles, dolphins, dugongs, jellyfish and other floating objects). There is a saying about Moreton Bay sailors "There are those that admit they have run aground and the rest are liars" As much as I love foilers, I doubt I'd risk one in the Bay outside the shipping lanes. I was at a regatta last month where 2 A class "Z" foils and a T rudder were destroyed. Expensive hobby!

Doug Lord · Dec 23, 2016

Moreton Bay

Thanks, g28-always interested in new places!

Vantage475T · Dec 23, 2016

ISO Trimaran

I'm just lashing together a prototype trimaran based initially on an old ISO dinghy which is 4.75m and would fall under this category.

I will start a new thread on it shortly, I currently am finishing attching the frame, trampoline and epoxying the first outrigger.

Plan is once this initial stage is sorted so it cna be sailed this spring, to replace the ISO dinghy with a bespoke hull using all of the ISO kit I have spare.

My work is very busy until February now so I probably can't dunk it in the water for initial testing for a while yet but I can start getting some info up about it and wait for the derisive comments.

Doug Lord · Dec 23, 2016

Banshee Ambulance

Have you seen the "Banshee Ambulance"? It's a Cherub dinghy made into a trimaran:

shipwright · Dec 23, 2016

Attachments

Hi Troops: I am having difficulty uploading an attachment. only file to attach is autocad which few will have, DFX-PDF Comes up as invalid file. any help?
shipwright

shipwright · Dec 23, 2016

Moreton Bay

Hi Troops: luv your comments re the Bay, it can be amazing to see the real estate visible when the tide goes out, tide height can vary but average 2m.

Re: the proliferation of square headed main sails these days, they bring back recollections of our older boats with a gaff top of the sail was basically uncontrollable for twist, as is the modern square top ,every photo you see has the boom sheeted in tight, but the square top has considerable twist.
it may work ok down wind.
Comments?
Shipwright

Doug Lord · Dec 23, 2016

click on "manage attachments", then "choose file", then "open", then "upload"
and that should work.

Doug Lord · Dec 23, 2016

square tops

Square tops need a lot of vang/downhaul but work well upwind and down. One of the advantages when set up right is automatic gust response where the sail depowers a bit in a gust-you set how much.

Pro and Con thread on square tops: http://www.boatdesign.net/forums/sailboats/squaretop-mains-46803.html

shipwright · Dec 24, 2016

Side View

Hi Guys: Xmas eve on my own.
See Side Elevation 6.3m Tri.
I sail with a Hobie group-social sailing,had a xmas meet at Wivenhoe dam.
o to 5kn for a while then a good storm arrived with 20kn had a terrific sail.
hardly move the next day.

Shipwright

SaminSamin · Feb 17, 2017

3 in One said: ↑

After I saw all the excitement about the new Astus 16.5 and thought I should share a few images of our little project.
It is a prototype 4,6m family oriented Trimaran that was designed and constructed by a friend that is yacht builder in Cape Town South Africa.
We have been sailing it for a year and have made small detail adjustments to the design. During the last winter we decided to experiment with longer ama's as a result the existing ones (we have a spare set of the original design) were cut in two and 900mm was added to the length of the ama's at the deepest part of the pontoons.
We sailed it in strong and light wind and it is brilliant, after a few more tests we will tweak the design and make them in Carbon to get back to the original design weight.
The hull is a vacuum bagged honeycomb glass fibre construction.
The main hull, beams and ama's weighed in at 138kg before we decided to lengthen the ama's, added here and there etc. we have not bothered to re-weigh it but it is obviously heavier.
The mast is a rotating carbon section (designed for this boat) with rope rigging. We recently added a system to adjust the shrouds primarily to control the fore-stay tension. A by product of this exercise was that we can now also adjust the angle of the mast sideways for sailing upwind if we feel the need.
The beams are carbon with very thin GRP fairings on the front, to reduce wind and water drag.
The jib, fully battened main and asymmetrical spinnaker were made by North sails for this boat, the jib and spinnaker are on roller reefers. We don't have a boom.
Because the wind conditions where we sail is extremely variable and mostly very strong in the summer months and gale-force in the winter. We opted for a safe sail plan (excluding the spinnaker it is a little less than a Hobie 14) until we have sorted out the hulls detail design.
We often sailed it at 14 Knots with two people on it with the shorter Ama's but found that the lee pontoon would become submerged in big gusts, It can now do the same speed with the longer ama's without submerging the lee ama, the longer ama's radically improved the boats longitudinal motion through chop, strong wind, on a beat, it now slices through it.
It is by far the easiest boat that I have ever sailed in any conditions, compared to the 505's I raced in my younger days this boat is an absolute pleasure.
You can sail it with novices take a cool box for a picnic or go wild in wind when everybody is heading for the shore.
I often sail it single handed, because it is a small boat it responds very to having less weight on it- I have sail it with the asymmetrical in the same wind conditions we would sail two up and it is stable, fast and fun.
Click to expand...

Looking great! What is the status of the project?

upchurchmr · Feb 17, 2017

Could you show us the post # of the 3 in one post above.
I went back 10 pages and didn't find it.

SaminSamin · Feb 17, 2017

upchurchmr said: ↑

Could you show us the post # of the 3 in one post above.
I went back 10 pages and didn't find it.
Click to expand...

That would be #623 ...

upchurchmr · Feb 17, 2017

Thanks, it would be nice to have the update and more pictures.

Cholsson · Apr 15, 2017

New Chryz10 small trimaran, Miami Edition

Happy Easter! I have built yet another small trimaran
Chryz10 Miami Edition. Had so much great material at home to build a new boat with. I have not test-sailed it yet. Its not that good weather in Sweden right now.

more info at http://smalltrimarans.com/ and at my blog www.chryz10.com
Also created a walkaround-video
https://youtu.be/m9f2KFmzra0

Will it float?

br
Chris

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Small trimarans under 20'

Corley epoxy coated

gypsy28 Senior Member

Doug Lord Flight Ready

Vantage475T Adventure Trimarans

Doug Lord Flight Ready

shipwright Junior Member

Attached Files:

3D-6.3m Hull.dxf

shipwright Junior Member

Doug Lord Flight Ready

Doug Lord Flight Ready

shipwright Junior Member

Attached Files:

General Arrangement-sail plan.pdf

SaminSamin New Member

upchurchmr Senior Member

SaminSamin New Member

Attached Files:

IMG_0643.jpg

upchurchmr Senior Member

Cholsson Junior Member

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