foaming mad!

Vivier recommends foam in the 3 flotation chambers for very good reason. If a chamber is punctured and fills with water, the vessel may list and become unsailable. I looked into foams. Polyethylene foam  (trade name in Australia - microlen) that Vivier states is the best is the only foam that our Marine Safety Authority in Tasmania allows on vessels in survey. I think the reason is that's the only foam that is truly non-absorbent over years and is also totally fuel and solvent resistant. The problem is that it's very expensive. One sheet (2.4m x 1.2m x 0.1m) costs about $260. I figured that I needed 3 sheets and gulped at the costs.
I spent a while thinking about other options - polystyrene, plastic bottles etc etc but then thought that, seeing as I am using the best materials I can everywhere else (Austral marine ply, Bote-cote epoxy, Si-bronze fastenings) it would be silly to put in a foam that I might regret and then never be able to replace (those flotation chambers are sealed shut with epoxy).
So, I bought the expensive stuff. One relief was that I accidentally thought that all 3 chambers were the same volume. When I double checked, I found that the rear ones were smaller and so I only needed 2 sheets of foam. $500 instead of $750 - sounds cheap now!!

almost full of foam

After putting in 3 coats of epoxy (and drilling the limber holes and adding the eye for attaching the anchor rode) I started packing the foam into the front chamber. I fit most of one sheet in here (about 288 litres and the chamber is supposedly 300 litres).

I then fitted the foredeck to seal it all in.

foredeck on

I then asked my wife, Briony, who is the best at doing 3-D type spatial puzzles in our family if she could fit the foam into the rear chambers. She did a very neat job!

nice to see a bit of beauty in the boat shed!

The polyethylene foam is very nice to work with. It's stiff and won't compress much at all but it cuts easily with a sharp sashimi knife and doesn't make any crumbly mess.

Decks are now going on.....

ready to deck

I haven't posted for 2 months and it's partly because I have not been building that much. As we also run a small market garden/vegetable farm, I had to do many jobs during autumn such as planting green manure and garlic, putting in new fences and building a farm shed to store our equipment that had been lying around for too long.
Anyhow, I have just spent the last 3 days working on the boat full time and it's been great. Even better is that I have the next 10 days to spend on pretty much pure boatbuilding.

Where have I got up to?

I have been cutting and installing the deck beams, half beams, the curved coaming backing, the mast staunchion.

forward

amidship

cockpit taking shape

staunchion with centre carling left slightly proud so I can plane the deck camber into it

nice to see the sheer line reflected in the coaming carling and flotation chamber battens

So now, I'm ready to put the decking on. But first, I'll paint the interior . I have already done 3 coats of epoxy in the flotation chambers. These won't get painted. I have also painted the stowage bins in the cabin and the lazarette. So now, I'll paint everything with one more coat of epoxy then use the high-build dtm-985 under the floors and a 2-pack primer everywhere else.

fit out progress

Just to prove that I have been working, here are some pictures:

I put in the beam and drain structure in the lazarette. I also painted the inside first so I wouldn't have to crawl in to do it. The bottom of the lower deck is also painted (except for the gluing regions). I have used wattyl DTM-985 again as I will in all lockers and the bilge areas. This paint is great. Direct to epoxy, it is primer, undercoat and topcoat in one. If you thin it to 10% of L760 thinners, you can roller it with a long nap roller. You get a slightly rough but incredibly tough surface which is suitable for these areas. It is also a high build paint so it will cover blemishes and glass tape weave, etc

lazarette drain complete

I decided that I want the boat to be stronger so I have incorporated cement! :0

So the bridge deck is on.....

bridge decks glued on

 and I also painted these lockers first for easier access

internal lockers painted

 I realised that I had forgotten to attach the little doubler/supports for the cockpit shelves prior to filleting the bulkhead/hull joins. Francois said that they were not required structurally but just an easy way to support the shelves. Instead, I have supported the shelves with battens

cockpit shelves installed

Now, I am adding the support beams for the helmsman's (i.e. my!) seat before I finish epoxying the side rear buoyancy tanks.

slowly fitting out

once again, I have been very slow and slack in updating my progress. There has been quite a bit of progress since the turnover day although not quite as much as I'd hoped. That's because, it has been summer and I have a very big vegetable garden that is slowly becoming a market garden and also because we've had such good weather that it's been nice to take a break every so often to go down to the cove and have a swim or a fish.

What have I done since turnover?

- clean out all the gobs of epoxy that I didn't clean out while planking

- lightly sand all the planking on the inside and round off the inner edges then fillet the overlaps (I used bote-cote resin but with West 411)

- epoxy coat then attach all floors

- fillet and glass all the floors and bulkheads and transom to the planking. This was a slow and tedious job but one I wanted to get right as these must provide much of the resistance to twist in the boat. I used bote-cote thickened with their glue and fillet powder (which I believe is mostly colloidal silica). I mixed the gunk thickly and applied it after painting the zone to be taped with straight resin. I shaped the fillet with a disc of pine wood. I made a whole pile of these by ripping cheap pine boards into 3-4 mm thick strips then using a hole-saw to cut 30mm discs. I sanded the edges and they worked really well. Then, the advice of Chris Burke, a proper boat builder who works at Denman Marine, was really useful. Chris told me to polish the fillets with my gloved finger dipped in methylated spirits. He also told me to wet out the tape on a flat surface covered with a piece of plastic then put it over the fillet already wet. This was fantastic as it meant no squeegeeing of epoxy on curved surfaces in confined spaces. I just used metal roller with ribs running across ways to roll on the wetted tape and remove air. I then used a heat gun to further remove air from the surface and make the epoxy settle in. I used 420 gsm 45/45o biaxial tape and this conformed to curves really well without needing to have darts or nicks cut into it. After the epoxy went tacky, I rolled on another coat of straight resin using a shaggy roller.

floors in the cuddy

 Sanding all these fillets was a real pain but I'm hoping that the paint that I will use in the bilge and locker areas (which I also used under the waterline on the outside of the hull - Wattyl DTM 985) will be high enough build that it will fill and obscure any of the surface imperfections. And, hey, it's just the bilge and lockers!

I have also laminated the sheer clamp/beam shelf. As I am using swamp gum/mountain ash for this, I found that it was going to be way too stiff and difficult to try and glue in both pieces at once, so I did them separately and this worked well. I used bote-cote high-strength filler for the glue and a huge number of clamps ( I had to borrow some). The sheer is now really nice and smooth with no irregularities at all. I planed off the beam shelf with the deck camber allowed for. Gee this boat is going to be strong! Mine will, according to FV be about 30kg heavier, but it will be a whole lot stronger as the hoop ply I am using is F17 whilst gaboon is F8 (the hoop has many more laminations) and the swamp gum is >F17 while douglas fir ranges from F7 up to F11.

beam shelves in place 

Next, I put the longitudinal bulkheads, that define the flotation chambers, in place. They required several minor adjustments (shaving with a plane) and then I glued and filleted them in place. Vivier didn't say to glass these in, I don't think, but I am doing it anyway.

watertight compartments in place

I have also commenced building the rear lazarette having glued on the side stringers and the cut in and glued the beam that supports the top of the compartment.

stringers and beam in place

centreboard pattern

Right now I'm mostly working on filleting and glassing the floors and bulkheads. This is tedious work but I'm close to done and a post will be forthcoming.
As a small sideproject, I have been making the centreboard pattern for casting. Mike Randall was very generous to send me a full size PDF that he made from the plans of the centreboard. I got this printed and was shocked but also excited to see how big the centreboard will be.
I cut out the paper patterns for the centreboard shape and the foils and then marked these onto MDF. After cutting and planing these pieces to size, I glued them together and glued in slabs of polystyrene foam.
The fun bit came next. I borrowed a hot wire cutter from a friend who makes model aircraft wings using this same method. This was a 1 metre long wire connected to a power box that I could tension or slacken as required and I simply dragged it along the foils to hot cut the foam and get the shape of the centreboard.

I have now coated this with a layer of fairing compound to allow me to sand it smooth (there are surface marks because I was not so good with the wire) and then I'll send it to the foundry for casting.

turnover day

Without planning it to be auspiscious ( because I don't believe in that stuff) Turnover Day ended up being on the 1st of January.

All went smoothly. I had friends come over at 11 am. Beforehand, I made cinnamon scrolls and detached the boat from the jig and got my trailer ready.

8 of us lifted it off the jig and most of the molds fell out as we were moving. We walked it down off the platform onto the grass and rolled it over gently onto two mattresses mostly missing the mattresses (lucky for the soft grass).

Then we positioned the trailer in place and as we winched, we pushed the trailer so that the boat didn't have to slide. The trailer was then backed into the shed once again and I used a laser level to set up up level.

A milestone for sure but I know I have a lot of hard work ahead of me!!

brass protective strip

The last job to do before turning the hull over was to attach the brass strips to the bottom of the hull to protect from abrasion. I bought 19mm half-oval brass strip at great expense and the cringed at the thought of putting holes in my hull to screw it on. I talked to a few people who recommended an adhesive called fixtech 190 that would be better than screws, which I believed, but I still needed some way to hold the strips down while the glue cured.
So, in the end, I bit the bullet and used screws through the brass to hold it in place and used fixtech 190 as a glue/bedding compound (it is very flexible stuff).
I wanted to have no plywood, especially end grain, exposed to the elements so i did it this way. I drilled and counter sunk all my holes in to the brass strip (400mm apart). I then used self-tapping screws to attach the strips to the boat. I removed all the screws and the strips. I then drilled 10mm holes using the hole left by the screw as a guide. these holes were went in approximately 12mm into the 16mm plywood of the sole.

 I then mixed some bote-cote epoxy with TPRDA and used a pipette to fill each hole and allowed the stuff to soak into the grain then I sucked the excess out. I then filled the hole with silica-thickened epoxy

 and before it was fully hard, cut it flush and drilled holes about 10mm deep in their centres. These were then used to attach the brass strip using silicon bronze wood screws and fixtech 190.
A tedious process but I feel secure knowing that there's no plywood exposed at all.