'Laser Ketch' rig

To balance the rig better, we tried a laser 4.7 rig at the back.

For those unfamiliar with this rig, it uses a shorter bottom section of mast, with a slight bend to put the centre of effort of the smaller sail in the same place as the normal one, when used on a laser. That's why it's tipping back. It looks a bit silly and I should move the mast foot to keep the masts parallel, but it worked.

We had a nice sunny day with the force 3 that's typical summer weather at our lake, with a few gusts up to force 4. Liz's boyfriend Mathew joined us, which I think is only his second time sailing. With an extra willing pair of hands, carrying everything down to the beach and rigging up went faster than usual and we were soon afloat and chasing a Laser2000 that was the only other boat out. Most of the time we were similar speeds, in the gusts we were slightly faster but he was much faster to tack.

We discovered that I could cleat off the aft sheet and Liz could balance the sails and even steer with the fore sheet, leaving the steering oar for when we needed to steer quickly or tack. Mostly we'd tack without the oar, just letting the fore sail go and allowing the boat to round up into the wind, then backing it to force the nose around. Backing both sails on opposite sides also spun the boat usefully but we didn't usually bother.

I could speed things up with a few strokes of the oar but it wasn't really necessary. Using the oar to steer around a tack required it to be on the right side, and it's quite unwieldy to move around so I mostly left it on one side. It could still be used very usefully to row the boat around once we'd slowed down. The oar isn't as good as a rudder for normal sailing. While it is now quite powerful and precise, and doesn't twist or bend (much), the handle end is at about shoulder height and can catch on the boom. When I was standing up in the aft cockpit it feels great. When I was sitting on the hiking bench or safety ama I could still reach but it's a bit high for comfort and I don't have the range of movement that I'd have with a tiller extension. That said, the ability to scull, and to row the boat in a circle are huge benefits that I wouldn't have with a rudder.

I'd made a new off-centre board from 2x4s, cut in half to make 2" blocks, planed smooth, switched around to alternate the grain direction and spread the knots around, epoxied and shaped with an electric plane. Other build-logs make this sound like a huge amount of work - maybe they used a hand plane because it only took an hour or so to form the aerofoil shape. It did generate a huge amount of wood shavings though - I filled my 50lt dust collector and blocked the hose a few times. The finished board is about 40mm thick in the middle and feels immensly strong so I see no need to glass it, just a coat of Woodskin. I turned the old steering oar into a second paddle and Woodskinned the steering oar. Did I meantion that I love Woodskin?

It's hard to say how effective the centreboard is, but there's clearly a fair bit of force on in when we're sailing so it must be working!  Putting it down when it's to windward was tricky as its handle wanted to jam under the gunwale. I had to put my foot on the far end of the board and push it down and under the boat, which created a lot of spray and a noticeable amount of drag. Once down, this board created a lot less spray than the old one.


Back to the sailing: we tacked up to the top of the lake and then goosewinged back down for lunch. Running with this rig was lovely, fast and effortless. The two different sized sails didn't quite balance and needed a small amount of correction from the steering oar. We tried putting more weight on the ama side but it didn't help much - I'm surprised how little drag the ama has, even with 3 meters of leverage. Liz tried to balance the boat with the ama flying, so we alternated between dragging the ama, flying it, and dragging the safety ama for a while, but there was very little affect on the steering. Surprising, but nice.

After lunch the wind had risen a bit and we needed two people on the hiking seats to stay level, and the safety ama saved us several times. There's no warning when the ama lifts unless you're actually watching it or watching for gusts. It's quite a gentle process, taking about a second from the sudden quiet as the ama leaves the water to the safety ama touching down on the other side. Initially the safety ama rides along smoothly, but as it gets deeper it splashes more.

Here are a couple of short video clips that Mathew took:

https://youtu.be/zl5cHORcUcs
https://youtu.be/EUeRqE9pf1w

New steering oar, an AD scull.

We had another sail today, in a very light wind.

Initially there was no wind and we went out with no rigs. The new paddle worked well, moving the boat at a pretty good speed, even with just one person paddling. I'll have to make some more because I'd love to see how it goes with four people paddling. We paddled and sculled across across the lake and back (total about a mile and a half) pretty easily.

I had made a 12 foot steering oar (it was originally 13 foot, but I had to cut it down to fit in our van) with an asymetric blade, based on the 'AD scull' idea but largely guesswork because I couldn't much information. My new rowlocks are apparently slightly different sizes, because the oar was a nice snug fit in one, but too tight in the other and wouldn't rotate, so I could only scull when the oar was on one side. I found sculling to be quite natural and very quick to learn and about as fast as paddling but with much better steering control. I tried rigging up a line to hold the front of the oar down and sculling with one hand on the line, but didn't find it useful. There wasn't much force on it, and it didn't seem to help control the angle of the blade - maybe there are subleties I've missed.

Later a light wind arrived and we put up the sails, this time with kickers on both sails. There was still a little weather helm, even with the fore sail over sheeted and aft sail eased a little - however it was easily overcome with the steering oar, or just by moving to the aft cockpit. Here are a couple of short video clips, showing how the two sails push us along at quite a reasonable speed in almost no wind.

https://www.youtube.com/watch?v=3ALma58dqew
https://www.youtube.com/watch?v=KRgtCrqZUpE

I've made a new, much stronger centreboard, but the old pivot bolt is too short so we were sailing without it today.

Finally, here's a short clip of us playing with the new safety ama, experimenting to see if we could use it to tack the boat. Tipping the boat didn't really affect its course, and left me a bit trapped behind the sail, so we won't be doing this regularly. It is however a good demonstration of how gently it settles into the 'tipped' position, and how much buoyancy there is.

https://www.youtube.com/watch?v=yqlkUDq1a9U

We also checked that we can both stand on it without sinking it.

First sail of the full size Wa'apa

Today we made it onto the water with the new middle section (making 24 foot), extended trailer, safety ama and twin laser rigs.

Things that went well

Today's wind started at a force 4 and now we have twice the power we were going pretty quickly but it was a bit too much for Liz to balance on her own. The safety ama saved us several times, touching down in a very smooth, progressive way and giving us plenty of time to release the sheets. Unlike the drain pipe, there's no great explosion of spray and reduction of speed when it hits the water. I'm very happy with it. It's nice and light to move around too.

The reshaped steering oar was a big improvement, removing all the twisting force and making steering much easier - but it's much too short, I had to sail from the rear cockpit to reach the rowlocks, which meant I couldn't help balance the boat. It also bends alarmingly - I need to beef it up, and maybe cut it down to be an ordinary paddle.

Tacking with two sails was a huge improvement, over both the single laser rig and shunting the crab claw rig. We'd sheet in just the rear sail to head up, then when almost head to wind Liz would back the foresail to push the bow around, then sheet it in to bear away. We did some tacks without the steering oar but found the oar useful on the tacks that put the ama out the outside of the turn. Occasionally we picked up quite a bit of speed in reverse but backing both sails on opposite sides still turned the boat with ease.

The new beam lashing arrangement worked well, saving lots of time at the start and end of the day. One end of the rope is attached to a hole in the seat, the turns just go around blocks on the outside of the boat (no more fiddly holes) and the running end is secured to a cleat (no more dodgy knots). It's just about visible in the picture above.

Things that didn't

There was a nasty splintering sound almost as soon as we powered up, and the centreboard folded at it's pivot. I couldn't see any signs of rot, I think we just expected too much from half inch plywood. It even broke the two inch thick handle that was supposed to reinforce the pivot! Fortunately we didn't really miss it as we were just reaching back and forth.


More seriously, the rigs aren't balanced. I couldn't apply much power with the aft sail without the boat heading up into wind. This meant I needed the oar to keep us straight, and thus needed to stay in the aft cockpit to give the oar something to lever against. It's possible that this is just because we didn't have a kicker (vang) on the front rig, or we may have to try a smaller sail at the rear (laser 4.7, maybe even an optimist rig!). Moving the rigs forward would involve a hole in the forward watertight compartment, and moving the centreboard would mean not using the nice reinforced pivot I've built in the middle of the boat, and possibly drilling a number of holes the find the right spot.

Anyway, we had a blast and have a fresh set of problems to solve.

Other thoughts

I also spent a while sailing the clubs training dinghys for our open day, and it was an interesting comparison. The Wa'apa was very dry to sail, while the Wayfarer smashed into every little wave and sent sheets of spray over the crew. It was fast but also very relaxed without every gust or lull tipping the you over (although not relaxed enough to take photos - the oar is a two handed job!) It's also very light - I could move it around on our little dolly on my own, even on a slope with slightly soft tires.

Here's a picture of the boat on it's trailer, with the safety ama on top - pretending it's a much bigger boat with a cabin.

The trailer worked well, but doesn't have a lot of ground clearance at the back. The lighting board was knocked off when we hit a rock in the roughest part of the track in the dinghy park.

Spring update

Spring is finally here, and while we've not had much nice sailing weather, it's time to get ready for the season. Building the middle section of the boat was only a fraction of the work that is required to actually sail it. I really want to try sailing a two masted boat, so I plan to use two laser rigs. One will go in the mast step and partner that I used in the 16' boat, and another will go in a new step and partner somewhere in the middle section. So I've made those, and another mast extension.

The spare step is so I can rig the boat with a single sail, for when it's really windy.

As we capsized a few times last year, and the drain pipe didn't have enough buoyancy to support us, I've built a 'safety ama'. This will slip onto the ends of the beams on the side opposite the existing ama. It won't touch the water unless we're about to capsize. It's made from a single 8x4' sheet of 6mm exterior ply and should have over 200 litres of buoyancy. The edges are all covered in glass tape and epoxy. It would have been much easier to build if only the bottom was cuved, but I've curved the 'outside' too. This meant that the beam sockets had to stick out, and one seam has a tricky double curve but I think it looks better and heopfully there will be less slamming and splashing when it hits a wave. Here it is, in front of the rest of the boat, which has spend the winter stacked up in my garage.

Also in the photo is the modified steering oar - I've removed half of one side to make it more balanced. That might sound wrong but the centre of pressure of an aerofoil is 25-33% back from the leading edge. It may need a bit more off because it sits at an angle in the water. It probably also needs to be about a meter longer and have a thicker shaft but I want to get the blade shape right before building another. Another minor improvement is some proper rowlocks for the steering oar. The 'two peg system' I used last year limited the steering angle and nearly broke a few times.

Next to the steering oar is a paddle - I had been using paddles that I made (rather crudely) a few years ago for children in Optimists but they were a bit short, had small blades and had been left out in all weathers. This one might be too big, but like the steering oar, I can always cut it down.

A longer boat needs a longer trailer. I'd picked a trailer that used a scaffold pole for it's spine, so it was relatively easy to fit a longer pole. I say 'relatively' because while it's easy to buy scaffolding on-line, the postage on a 21' steel pole is ten times the price of the pole - no wonder they sell them in packs of 100! Eventually I found a local company who would sell me one of theirs and deliver it when they were passing - thanks Worth Scaffolding! The diagonal braces were looking a little rusty, so I replaced them with some much beefier scaffold tubes that will also support a wooden bearer for the boat. Here's a picture of it as we were building it, looking comicly out of proportion due to our camera's wide angle lens.

Another 'little' job was extending the boat cover - unpicking about 5 meters of stitching and sewing a new panel in the middle. Now I'm just waiting for a few odds and ends and we're ready to get back on the water.

Middle section complete

It's slightly too late for the sailing season, but I've finished the middle section and now have a 24' wa'apa.
Here it is, assembled for the first time in my garden.

I made all four bulkheads at the same time, so all three parts line up well despite not having the ends for reference when I glued the centre section together.You can see the reinforcement for the leeboard in the above picture - the bolt goes through the central frame, which is also reinforced.

I think I need a longer, stronger steering oar but can reuse the bracket I made earlier. It should lash to the holes where the aka used to go, where it is in these pictures (but straight)

The aka lashings are copied from Mr D's later design, 'Tamanu'. I remove the akas for storage, and threading the lashings though holed in the gunnels is quite fiddly - and threading them through holes in a seat would be worse (it's bad enough with the mast partner I added). This way I can just wind the lashing around a block. The construction was slightly complicated by the block being split between two parts of the hull, and having to interrupt the gunnel but I think it'll be well worth it. I'm still undecided about using cleats to finish the lashings.

Right now, it's all in my garage, ready for another coat of International Woodskin. Some parts didn't get the recommended 3 coats last year but have held up very well. I really like how it copes with the wear and tear of lashing wooden parts together, something that would be a real problem for paint or varnish. After that, I'll need to extend the cover and trailer, and build a second laser mast step and partner, and maybe a safety ama and some buoyancy bags, because we're bound to capsize a few times with that much power.

A minor update

We went for another sail today after making a few minor changes to the rig (which always seem to take ages and result in tangles). I added small blocks to the bows for the backstays to reduce friction, and stretched the backstay bungies all the way to the opposite bow to take up all the slack. This made shunting a lot easier, as the slack used to get caught around the boom jaws. The bungies still aren't powerful enough to lift the rig when the tack line is released but it's a lot easier than it used to be to pull a backstay to position the mast.

The next step is another length of bungy; the book mentions 3 lengths of 6mm, so I'd hoped that 9mm would be sufficient, but I guess not. We still have to be careful how we handle the sail during a shunt. It's easy to spend too much time getting tangled and not notice the boat spinning into the wind. It's too easy to be standing on the mainsheet, or the wrong side of the tack line and end up in a mess.

Here's another short video of us sailing: https://youtu.be/1nqyQFIQIgI

Meanwhile, I've started building the middle section. It feels much faster than the bow sections. Maybe I'm getting better, maybe it's easier or maybe it's because there's only one of them...

First outing with the Crab Claw sail

We spent a couple of hours trying to work out how long all the lines should be, where to attach them and how to adjust them. After the simplicity of just plonking in a laser rig, it seemed pretty complex with lines everywhere all only a vague idea what it was supposed to look like.

Then we went for a sail to try it, and even managed to take some short videos.

https://youtu.be/lR_2MyIq5xc
https://youtu.be/RVYTApxmJw0
https://youtu.be/Q0LVeRyGtbM

I forgot to take any photos though.

It's a very different experience to the laser rig, in several ways.

• The boat doesn't feel stressed, even in gusts that would have had the laser mast groaning in it's socket. The shroud and backstay take all the load, so there's very little no load on the beams or twisting the hull. A 2:1 mainsheet was easy to hold and a lot of the time we just held both parts.
• There's no need to tack or gybe. The long hull with very little rocker doesn't turn easily, and tacking got harder as the wind got stronger. Shunting is still very new to us, and we kept getting tangled, but it felt natural for the boat and there are no large forces involved.
• We didn't need the steering oar. It spent most of it's time bungeed to a hiking bench. The boat would naturally turn towards the wind, or bear away if we pull the sail in harder, which didn't seem to affect the speed - just like it says in the book. 
• Hoisting and dropping the sail while afloat was really easy.
• We got taken aback a couple of times and the rig fell down. With the relatively lightweight windsurfer mast spars, this wasn't a big deal. We found it easiest to free the halyard and pull the sail to the mast foot, then the mast could be raised with one hand and the sail hoisted.

There are still plenty of things to work on though.

• I'd like the sail a little higher on the mast, to move it forwards because the boat wants to turn into the wind a bit too much. That will require a longer shroud and back-stays.
• The tack line is too thin; we're handling it a lot so it needs to be an easy size to grip, not just sized for the relatively light load it carries.
• Bungee powered back-stays sound wonderful - I can't wait to try them.
• Brailing lines, we'll probably need them at some point.