Saturday, December 17, 2011

Taming the Leeboard


A leeboard at monohull speeds doesn't make much spray, but at multihull speeds can throw up enough spray to get you wet if you're hiked out above and behind it.  While you want a blunt radiused leading edge below the waterline, this is not ideal at the water/air interface.  
So I've reshaped the leading edge at the waterline area to a sharp knife edge.
Sailing tests yesterday revealed a vast improvement with the board making no fuss at the leading edge.  You can still get splashed going into a steep chop where the water hits the upper part of the board, but the improvement in smoother conditions is well worth the modification. 
This will work with rudders too although the spray from it will normally stay aft of the crew.







The red line represents the basic NACA0010 foil shape commonly used on daggerboards and keels.  The black line shows the removal of material to produce a more "wave piercing" shape at the waterline.

Sunday, December 11, 2011

Ghana Wa'apa

Christopher Collins has built and is sailing his Wa'apa in Ghana, West Africa.  The ama is inflatable and most of the spars are bamboo.


He is using a double lug shunting rig.  You can see more photos on his blog:  http://ghanawaapa.blogspot.com/

Monday, December 5, 2011

Another Amazing Episode of what it's all about

Chris Grill continues on down the Mexican coast:
http://grillabongquixotic.wordpress.com/2011/12/05/running/
If this doesn't give you sweaty palms, nothing will.

Thursday, December 1, 2011

Rolling and Furling

I've refitted my Ulua trailer with rollers to take the Va'a Motu.  It passed the 65 mph test with no wobbles.

I had to build support brackets for each crossbeam to make it secure for rough roads.

With the weather still not that great for sailing, I was inspired by this article to build a roller furling setup for an old jib I had.  Cheap and works great. 
If I want still more power, I could always put on a bowsprit and a roller furling gennaker :-)


Saturday, November 19, 2011

It Folds!


The hinges may be a bit industrial looking but they do work. I avoided countersunk heads because it's a nightmare cutting big countersinks in stainless plate.  Perhaps some paint will help to disguise them.


Next sail will be in mild weather because this is one part of an outrigger canoe that do not want to fail.  I've left enough metal in the brackets that I would be able to go to larger size pins if I see any distortion in the 5/16" (8mm) ones I have now.

Thursday, November 10, 2011

Crossbeam Hinge







It's time to make my outrigger foldable.  I'll do this by hinging the crossbeams so that the ama can be lifted and pivoted over the main hull, thus reducing the overall beam to a legal trailerable width and avoiding the lashing and unlashing that gets old fast.
I've built a mockup of my Va'a Motu's forward crossbeam and am using 1/8" (3mm) plywood in place of the stainless steel plate I will use on the real hinge.

The beam is hollow with 3/4" (19mm) timber top and bottom with 1/4" (6mm) ply on the sides.  The timber on the Va'a Motu beam is actually two layers of 3/8" laminated together.


I drew a careful line where the beam will be cut and glued on two 1/8" plywood spacers that allow the hinge parts to slide past each other.


The 1/8" ply pieces that you see will be stainless steel plate and the fiberglass pins will be 5/16" stainless. I drilled pilot holes for the fasteners to make sure that the beam stays straight when it is reassembled.
 





I cut the beam in half with a thin kerf pull saw.


A bulkhead and side blocking to a depth of 4" (100mm) are glued into the cut ends of the beam to reinforce it.

The hinge plates are screwed into place and the pivot pins installed.  The real hinge will use epoxy bonded machine screws for fasteners.  The pivot pins will be drilled for locking pins and you only need to remove the bottom pin for the hinge to operate.

And there it is.  It seems stable enough for the job, so I'll hunt down some stainless plate and get to work on the real thing.

Wednesday, November 9, 2011

Rarotonga, Cook Islands

 From the Cook Island News
Of the boats he's built, Brent Fisher has named three for his family, blending the names of his children with that of his wife Annie.
Theres the Lou-Anne, the Peka-Anne now serving fish and chips as the Flying Boat and then theres the Corey-Anne, which is making its comeback after a 20-year hiatus.
Corey Fisher is building a business out of his namesake. Hes started up Fishin Tourz aboard the Corey-Anne, which he moors at Avana. Adorned with a Tangaroa carving by Mike Tavioni, she is a 26-foot outrigger.
I just enjoy taking people out, so I decided to put her back in the water, he said.
Fisher says he takes people out spearfishing, fishing and cruising for $90 a pop. The price, he says, includes all gear and transfers to and from the wharf, and up to four hours of angling.

Wednesday, November 2, 2011

The Need for Speed

A little more wind this time.  Boat speed peaked out at 9.8 knots (18 km/hr), but I will get out in stronger conditions to eventually reach my target 12 knots. 
The figure eight loop knots at the ends of my Spectra rigging are tightening and causing the rig to loosen up, so I've been adjusting them after each sail.  I've also moved the shroud attachment points 4" (100mm) farther aft for better support on broad reaches and runs.  I do this so you don't have to :-)
The GPS is showing a true 90 degrees between tacks which is better than the other rigs I've tried on canoes.  I guess there is something to having a tall narrow rig for going upwind.

 The shrouds are 5mm Spectra tied around a SS thimble.  A length of yellow 3mm Spectra is used to tension the shroud.  The shroud is attached to an aluminum tube that is lashed fore and aft to the main crossbeams.  The 50mm tube also supports the hiking seats.

Sunday, October 30, 2011

The lazyboy Effect

Finally got a little more wind, maybe 10-12 knots.  As an experiment, I lashed on a pair of old rusty beach chairs onto the hiking seats.  Amazing!  Total comfort and no more backache from sitting on a hiking seat for hours at a time.  Now for some drink holders :-)
Yesterday I peaked out at 7.7 knots of boat speed according to my GPS.  


I never had a proper mount for the GPS, but even if you have one it exposes the instrument to flying sheets and halyards.  There are already too many things to catch lines on, so I built an internal mount with a small plastic window in the aft water tight bulkhead.  A short bungy holds the GPS in place.  I like it.

Friday, October 21, 2011

Fiji was Perfect

Twelve days in Fiji is never enough, but at least I'm coming back to a new canoe and some spring weather.  Went sailing for a few hours everyday, caught some fish, drank rum and cokes for sunset, read some books. 
The Tamanu was in great shape stored under a house with the exception of forty pounds of mud dauber/mason bee nests that we had to scrub out.

Wednesday, October 5, 2011

Back to the Tradewinds














After a winter with little or no sailing but a lot of sawing and sanding, it's time to return to Fiji for two weeks.  The Tamanu is disassembled and stored under a house there.  Hopefully the parts are all still there and in good condition.















This what our cruising ground looks like.  Lots of islands and coral reefs to sail around and chase some fish.

Monday, October 3, 2011

Second Sail

Lately the weather has either been no wind or 40 knots, but today I had 4-8 knots of wind and sunshine so I strapped on the GoPro chest cam and launched.  Gliding around at 4 knots is better than nothing.


Wednesday, September 28, 2011

The Safety Ama


I've been cursed by a week of dead calm and cold weather, so no more sailing yet.  It was, however, a perfect opportunity to build the safety ama, an optional strap-on smaller ama that can prevent a capsize in those moments of inattention or a jammed sheet line.  It is still possible to capsize 180 degrees even with this extra ama, but it is held in place with just two quick release straps that can be released in the water to aid in righting the canoe.


I had enough foam left over from the main ama and shaped it without any central web/stringer.  It is also meant to be used as a primary ama on any smaller canoe that I may develop in the future, so the angled struts may look a little off when used as a safety ama.  It weighs about seven pounds.

A fiberglass dowel is glued into the bottom of the kiato and fits into a matching hole in the ama strut.  This prevents the ama from slipping out of the lashing.  The lashing is webbing with a spring loaded grip.  A good coating of fish oil keeps these going for many seasons.



Wednesday, September 21, 2011

Launch Day

Conditions finally calmed down so pushed him into the water for a first sail.  Sorry no sailing video or numbers yet as I wanted to fully concentrate on all of the parts of the canoe and see if anything needed changing.
It certainly tacks the way I had hoped, and not like any multihull I had ever sailed.  It comes around as quickly as a little sailing dinghy.
I only had about 10 knots of breeze but the speed seems as good or better than my other canoes.
A few things need to be done before the next sail.  It needs a stop thingy on the rudder so that when it's pulled down it stops at the right angle and the mast slot needs a pin so that the slugs don't fall out when the sail is lowered.
I now know more about the effect of curved masts.  The mast is a rotating one and having the head curved aft has the effect of over rotating the mast to the ideal angle.  Normally with rotating masts, you need control lines at the base to pull it around more than the sail would naturally do, but this one does it automatically.
The wind looks even lighter today so I'll concentrate on the details yet to be finished.


Wednesday, September 14, 2011

A Hoist at last

Several things conspired to slow down progress:  The curved mast that was such a good deal turned out to cause innumerable nightmares when making a sail for it.  In the end after days of re-cutting and changing battens to less stiff ones, I finally got it to hoist without jamming halfway up.  I'm happy with the shape in the end but don't recommend pre-bent spars to anyone.
Meanwhile I caught a stomach bug that was going around and can only work for an hour before I have to rest for two.  Things are improving.
All this week the wind and squalls have been blowing through my front yard at over 40 knots, making my sail and mast fiddling more difficult than normal.
Sometime next week I should get out there on the water and see what happens.


Tuesday, September 6, 2011

Sail (remaking)

I'm cutting down an old Tornado sail for the Va'a Motu.  The mast I have has a built in curve so I can't use the old luff of the Tornado sail.  I traced the curve of the mast onto the sail and added a percentage of luff curvature to that.  I'm using plastic slugs instead of a boltrope so that the sail comes down easily without me having to pull on it.

A few more jobs left to do on the hull: a shim between the leeboard and the hull side to make the leeboard aim straight ahead, make a tiller, and a snubbing horn for the sheet.  

Saturday, August 27, 2011

Hookup

I leveled everything up on two planks and blocked up the ama to the right height.  The forward kiato is connected to the ama with four struts so I drilled holes through the skin and deep into the foam until I hit the center web.  I poured epoxy thickened with microspheres into the holes and inserted the 1-1/4" dowels.  The aft kiato only has a single vertical strut installed in the same way.  The pitch trim of the ama can be adjusted by moving the lashing point on the aft strut.

Tuesday, August 23, 2011

Ama glassing

 I finished the final shaping of the ama and got it ready for glassing.  It gets two layers of 6oz cloth with an overlap at the keel and deck ridge.  I glass one side each day with both layers going on at the same time.

The new bottle of hardener I opened had turned red which is annoying but doesn't affect its effectiveness. 

Saturday, August 20, 2011

Rollout


It was time to give the Va'a Motu a little sun.  I'd have liked to roll it into the water but the ama still has to be fiberglassed.  There will be hiking seats on both sides when I get them made.  I also need to make the hull seats but am working on ideas to make them easily removable.


Tuesday, August 16, 2011

Ama shaping

Four hours of sawing, power planing and long board sanding later and it looks about right.  The sharp edges will be rounded to take the fiberglass.  The sanding is done with very coarse 40 grit paper to reduce the possibility of delamination later.  You sand for fairness but not smoothness.

There is an excellent resource on shaping and glassing polystyrene surfboards here:
How to build your first surfboard.
And if your really serious, you'll want to read Burt Rutan's "Moldless Composite Aircraft Construction"

Monday, August 15, 2011

The Ama

Two layers of 5" (125mm) polystyrene foam with a plywood web/stringer glued in between.  The vee side will be the top, but he bottom will be round.   I like amas to shed water quickly when rising out of a wave. 
Now all I have to do is cut away everything that doesn't look like an ama.
Unfortunately I have some paying work that needs my attention, so progress will slow down for the next week or so.

Monday, August 8, 2011

Hull paint

The outside of the hull is now painted and the second kiato is glued up.  Now it's time to drive over to the big city and find some foam blocks for the ama.

Thursday, August 4, 2011

The Snake

 The first side panel ready to go on the forward cross beam ("kiato" in Tahitian).  I'll be interested to see how much spring-back I get tomorrow when I release it from the blocking.  I planed several feet of each end into a taper so it will be tapered in both dimensions.  Saves weight and looks more elegant.
Two coats of undercoat inside the hull after much sanding and filling. When I built the canoes in Fiji I used almost no sandpaper and didn't have a sander.  I just smoothed everything with a block plane and I must have saved dozens of hours of labor.

Sunday, July 31, 2011

Slow cure

 The temperature is low the last few days, so my bottom sheathing is curing slowly.  I mixed graphite powder into the second coat of resin and there will be one more coat after I do some sanding.  I doubt that the graphite will make the hull any faster or the surface any harder, but it does retard solar degradation and can be left unpainted.
The outer stem laminated in place with long temporary screws to hold it while the glue cured.

I decided to start on the forward cross beam while waiting for the hull sheathing to cure.  I stapled some polytarp down on the table first because epoxy won't stick to it.  I measured out the stations and offsets and screwed down a block at each intersection.  This hollow box beam will have lower and upper chords consisting of two 3/8" (10mm) layers of Kauri laminated together so I'll have 3/4" (20mm) of solid timber on the top and bottom of the beam with solid block spacers.

Friday, July 29, 2011

Favorite glassing tools

 Anytime you're applying fiberglass cloth to a reasonably level surface, a plastic spreader or squeegee is the way to go.  Just dump the resin onto the surface and spread it around quickly with the squeegee.  Keep spreading the resin until the surface is no longer shiny but shows the texture of the fabric.  Excessive resin left in the fabric will cause it to float up and you'll have to sand those bumps off later.

A carbide or tungsten blade scraper should be used before any sanding after the resin has cured.  It takes off the high spots and doesn't make any dust.
Tomorrow I'll turn the hull over and prepare to glass the bottom.
I now have a powerful stereo system in the shop and it seems to be making me work harder, I should have had it in there long ago.

Tuesday, July 26, 2011

Hatches and gunwales

I managed to find some plastic flush hatches that I hope won't leak too much.  I also installed doubler pieces to the inside of the hull at the cross beam and motor mount location.  Next job is to glass the cockpit floor, but may have to wait for a warmer day. 

The outer gunwales went on today too.  I still have to laminate an outer stem and round it off.

Friday, July 22, 2011

Closed up

Today I installed the cockpit floor, foredeck and after deck.  I will sheath the cockpit floor with fiberglass and lap it up 2" onto the side of the hull.  Now I have to go shopping for some plastic hatches and access panels so I can use all of that storage space below the cockpit and in the end compartments.
The cockpit appears that it will be just big enough for me to sleep in.

Thursday, July 21, 2011

Details...details

After what seemed like a lot of progress in the first 24 hours, reality sets in during the next 24.  All those fiddly little parts to make and fit inside take a lot of time and don't look like you've done much.  Several half bulkheads have been filleted and glassed into place to support the cockpit floor. 
 
While I plan to use a stayed mast that will step on the cockpit floor, I want to have the option of using one of my unstayed rigs later, so I fitted a strong plywood box structure to allow a mast to step right down on the hull bottom. I could have glassed in a section of PVC pipe but didn't have anything the right size.


The cockpit floor has stiffeners glued to its underside and will be put in place tomorrow.  The fore and aft deck are also ready to go. I always hate covering up all that work in the bilge.