Rip it out and start again

When I built Scratch I swithered between building the daggerboard, as per the original design, or the centreboard for which John had prepared an additional sheet of plans. In the end I went for the daggerboard on the grounds it would be easier to build and if others were happy with it, why shouldn’t I be?

I had two bad experiences with the daggerboard, once hitting a rock at North Berwick, and then hitting the only shallow gravel bank in Loch Ness. In the first incident the daggerboard jammed, and I could only free it by using the oar as a hammer – all the while drifting towards more rocks. In Loch Ness the glass on the board splintered and I cut myself quite badly. Both incidents were the result of my carelessness, and I will try to avoid doing the same again. I’ve also found the daggerboard to be difficult to raise and lower while sailing singlehanded, which makes sailing on and off the beach a bit tricky.

Last summer I decided the daggerboard had to go. I had to adapt the centreboard plans slightly for this retrofit, but is was mainly plain sailing – though of course it took longer than anticipated!

Here are a few photos of the project. It was a little while ago now and I’m a bit hazy about some of the details of what I did!

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Here’s the original daggerboard case. I’ve cut out the extension to the seat front that ran along the inner edge of the case (which the rowing thwart rested on). I’m making cuts into the rest of the seat front prior to cutting it off. I’ve already made the new board, but the only photo of that I can find is this one of the newly poured lead:

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Judging by the date on the photo, I made the board over the winter – I’d forgotten that!

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The adjustable ‘comb’ for the stretcher (footrest for rowing) has now been removed, and the slot cut in the floor.

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My (then new) Japanese  saw has cut the top of the daggerboard case off nice and cleanly.

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Trying the centreboard case for fit. A great deal of the project involved ‘offering’ parts up and making adjustments.

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Case log and horizontal for rowing thwart now fitted. Still all a dry fit.

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You can see on the right that I made a mistake cutting the slot in the floor – I forgot to take account of the fact that the actual case isn’t as long as the outside wall of the case.

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Gluing in progress. Clamps and screws.

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And the other side glued. It took a while to work out a sequence that allowed me to glue the case securely while only being able to work from one side. If one were doing this when originally building the boat, neither the seat nor the planks would be in place yet.

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Trying to work out how to rig the uphaul. The plans show a block well forward of the case, coming back to cleat near the front of the case. I wanted an alternative, as that set up (a) prevented someone sitting forward of the case, and (b) meant leaning right forward from the helm to work the cleat.

The long slot in the seat is the original daggerboard case. The hole to the left is just a gap in the ply sandwich that made up the daggerboard case. One end of the pivot pin lives in the long slot. I spent many hours fiddling with the washers, grease and nuts in that slot – and it was too small for my hand, so long nosed pliers, sticks with tape etc, etc. Luckily I could also access the gap from below as well, but still very fiddly.

At the top left of the case you can just see the aluminium plate that the up haul attaches to.

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Same stage, but from the other side. You can see the head of the pivot pin. The pin is below the waterline, so careful fitting was essential.

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These people were my saviours. The pivot pin is a stainless steel tube with chamfered ends; exactly the same width as the case – to the outside of the case. Trying to source this took ages. On the forums everyone says ‘go to a metal shop’, but there are very few small scale engineering business around here.

No tubes are available in the width required, and buying a short length – about 12cm – was tricky, most places wanted to sell metre lengths. Eventually I tracked down The Metal Centre which specialises in supplying small quantities. They also do some metal working – but unfortunately their lathe operator was on holiday. They sent me to George Brown & Sons est. 1828, where my wife’s uncle did his apprenticeship before ending up chief engineer on oil tankers. Very kindly someone turned my steel rod into a chamfered tube.

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Fitting cleats for the stretchers. Note two ranks – one for for rowing solo and one for rowing tandem.

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And the other side.

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Fast forward. I took the opportunity to scrape back the floor, and to repaint the inside of the boat.

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Boat standing on its side so I can cut of the bottom of the case – this was built over size to project below the slot. Fibreglass tape was used over the joins, and the old daggerboard slot blanked off.

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The slot covered with gasket to reduce drag. No idea if it’s necessary – opinion differed!

The centreboard performs wonderfully – so exciting being able to adjust the depth with a pull on the line, and being able to sail on and off the beach without a hitch.

I don’t seem to have taken my camera with me sailing since fitting the new board. When I do, I’ll provide an action shot.

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About Osbert Lancaster

Creating ripples to foster sustainability. Seeking solace & clarity on the sea by sail & oar.

8 comments

  1. Yep should have done this from the start! when sailing single handed and you are 5? ft away from the dagger board at the helm, a swinging job is the way to go,especially when you dont know the waters that well -Ive come to many a sudden stop on strange sand bars etc. Sounds like your board was a bit tight in the slot! A swinging board is more relaxing. Yep a gasket is worthwhile.You could do a bit more fairing on the alloy” edging to round it.That looks like one helluva lump of lead-I think you would only need about 8?lbs to make it drop but I guess the extra10??lbs weight helps when hard on the wind when it picks up a bit .Love that Japanese saw!

    • Osbert Lancaster

      Hi mike

      Dagger wasn’t tight, it just got crushed a bit!

      The weight of lead was specified by the designer, an such matters I follow his advice!

  2. Hey Osbert, I am building a stretched Walkabout and have been encouraged and challenged by your work. I have a couple of questions if you have the time. Where did you end up putting the main sheet attachment in the cockpit. Can’t tell from the pics, but looks like maybe a rope bridle across the cockpit connected into B5? Also are there any pics of how you set up the uphaul and downhaul for the rudder?

  3. Osbert Lancaster

    Todd

    Here are some photos – hope they help!
    https://flic.kr/s/aHskbg7nYB

    Any questions, leave a comment on the relevant photo in Flickr.

    Cheers

    Osbert

    • Todd Harris

      Many thanks Osbert for the rudder pics!

    • Hello Osbert, I enjoyed the story of the daggerboard to centerboard conversion. At this point my questions are, 1) what should I glass with fiberglass cloth tape and epoxy? I assume the inside of the hull bottom with the fist side plank, and the transom to the hull sides and bottom. Then probably the bottom of the boat up the sides a ways. 2) where did you put your bridle for the main sheet? Does it run across the cockpit at bulkhead 5 (the bulkhead forward of the mizzensail mast area)?

      • Osbert Lancaster

        Hi Todd

        Glassing: I followed the plans. From memory the bottom and lowest plank.

        Mainsheet: I used to attach this to the aft of the daggerboard case. Now that’s gone, I have a bridle across the floor, see link in earlier comment for photos (along with rudder set up).

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