Up hill

One of the unknowns with this design is how well a boat without dagger boards can go up wind. The KD650 is an asymmetric hulled Catamaran and is designed to be able to go upwind without boards.

Below is a Google Earth image from my latest outing with my GPS track overlaid. The wind was a good 15 knots or so and a bit gusty. I sailed from the top right of the image down wind and on to a reach then back up wind again with a bit of tacking. This is the Waitemata harbour in Auckland and the tide was coming in so I was going upwind against the tide. As I got closer to the bridge I was more going for speed than height, and having some fun :)

As you can see it is not bad, considering the pros and cons of the design I'm pretty happy with this performance..

Average speeds up wind were about 7 knots and top speed on this trip was 13.6 knots.

KD 650 Review

I have a done more sailing and cruising now with the KD650 and can report more good things about the boat.

It can sleep 2 adults and 3 children! Was a bit of a squeeze but it worked.

I have added a prod to help manage the jib and hold the jib when it is lowered (a furler would be good if I had the money). Also I have found a good spot for holding the inflatable dinghy up front (might look a bit strange but much nicer than having it on the tramp).

The bows feel quite boyant, I have done some down wind sailing in waves, it surfs waves very well (fun) and the bows never felt like digging in, though the leeward bow has punched through a few bigger waves it felt safe, I think this is helped by the hull flare in the inner sides. The boat feels very stiff with no noticible wracking.

Highest speed under sail to date is 9.6knots (using main sail only on a reach) haven't really pushed it yet or been in winds stronger than about 15 knots. I have been effectively sailing it single handed and taking it easy.

Those rudders work very well even when not fully down. At anchor I pull the rudders all the way up and the boat does not sail around at all, in fact the motion also at anchor is nice for such a light boat, I'd say this is another advantage of the slim hulls.

I have a couple of videos to share also.
First video is sailing with just the main sail averaging 8 knots https://www.youtube.com/watch?v=gTEtMfhBKsg.

And second video https://www.youtube.com/watch?v=l-WSbz8jymk with main and jib, finally! Please excuse the slack jib halyard, I tightened it after the video was taken but still in the video the boat is matching windspeed of about 6 knots.

And finally a picture which speaks for itself :)

It's in

Today with less than ideal conditions we put the boat in.

To launch it we put some wheels under the hulls and wheeled it down the ramp with it tied to a car to slow it down. Seemed a bit unconventional but it worked, but probably wouldn't want to do it that way on a bigger boat.

I have not sorted out sails yet, so it was a motor cruise for the first voyage. The 5Hp motor seems enough. Cruises around 6.5 knots, max speed 8 knots.

Still lots of small jobs to do, including sails, don't think I'll have enough money for new sails though. But I'm happy with how it is coming together.

Moving Day

Today the boat was moved near the water.

This was the first time I was able to properly see the boat, it takes some getting used to after all this time in the garage. The mast was temporarily raised to measure lengths and has since been lowered. Hopefully the boat will be launched within a week.
The day was a lot of hard work and this would not have been possible without the many helping hands giving up there time to help me. Thank you guys.

Tiller's

Here are some pictures of what I've been up to with the tiller's.

Here is the laser helping me line up the centre line.

Then based off the marked centre line I can work out the Ackerman angle for the tiller. The steel rule in the picture below shows the optimum angle for the boat.

Then I made the tillers to this angle. Much the same as how Hardy made the ones for his boat. These are PVC tubes wrapped in carbon uni at 0 degrees and then wrapped in carbon double bias. If I did it again I would probably use laminated wood as I would prefer the look of a constant curve to the tiller. I thought I could have a constant curve with the PVC but it was harder than I thought, hence the final resulting curve seen in the picture below.

I have been pushing myself a bit lately to get the boat ready hopefully for some sailing over summer holidays. As a result I haven't been taking as many photos for the blog as normal, but things are progressing for sure.

Looking back at the build so far, one thing that I wasn't quite expecting is that building the hulls was a much smaller part of the overall project than I initially thought.

Fitout rolls on

A few pics here of what has been happening with the fit out.

Here is one of the battery holders. These 7.2 Ah batteries are quite small but should be enough for what I need.

 

The picture below shows the finished depth transducer installation. It is mounted as an "in hull" transducer and hopefully will punch signals through the small section of solid GRP I made when constructing the hull. Also as you can see I have made a protective box to stop anything damaging or knocking the transducer off it's epoxy bed.

And here is where I have installed the display for the depth sounder. I chose this model for it's simplicity and low power consumption.

Obvious what is going on in this picture. The location for the porta poti is not as in the plans as this unit is a little to wide to be mounted at the forward location. But this spot is just as good. I made a raised removable floor for it to sit on. I had considered putting in a proper marine head, but recent changes to marine rules about discharge of waste made me think the extra cost and weight not worth it for my intended use, for now anyway.

I'm still enjoying working on the boat even after all this time. Though I've been putting in a few more hours lately as I hope to have it in the water for summer holidays :)

VHF

It is nice to be doing a few jobs that do not involve sanding or fibreglass. One of these jobs is installing a fixed VHF radio.

This picture shows where I have mounted it, in the starboard hull. I will be putting all electronics/switches for both hulls in this area so that they can be operated from outside by just leaning in to the cabin without having to go inside.

 

 

In this picture you can just see how I have made the hole for the cable. I drilled an oversize hole, then filled it with epoxy filler then drilled a smaller hole through the epoxy so hopefully this won't get water/rot problems later.

And here the aerial is fixed in position.