J-Bird III Restoration Series: Part 7 - A new design for the deck
by Ocean Crusaders 7 Jan 2021 07:04 GMT
In parts 1 - 5 we have explored the purchase, haul out and delivery from Sydney to Brisbane of the World's First TP52. We then stripped the interior of everything and cut the deck off due to severe balsa core rot.
Having cut the deck off, the biggest component of this restoration project was a new design for the foredeck. As mentioned in our previous blog, we wanted a cross between the new Pacific 52 Invisible Hand and the latest ClubSwan 50. So we turned to Alan Andrews Yacht Design to come up with the aesthetics. As the original designer, he had all the files on hand so no measurements needed, he just pulled up the old files and started to create.
This meant he could get the internal measurements very easily and this was a key point as we wanted good headroom for myself at 6'4 (192cm). During this period, America was going through the Black Lives Matter riots and portions of this were just 3kms from Alan's office so on several occasions Alan was delayed as getting to his office was just too risky. No boat design is worth risking a life for.
The first drawings that came back from AAYD showed quite a home-made look with square edges. The contours were a bit too high and whilst it was close, it just didn't appeal. It was suggested that we create a bigger radius on the edges of the cabin top to round things off better. It would involve us having to create this radius with strip planking but we needed to soften the lines a little.
We also compromised a little bit with head height. I wanted 6'8 at the mast, we settled for 6'7 ¾'s. Not a huge compromise but it certainly did alter the lines for the better. It allowed all the lines forward of the mast to be a little lower and hence blend better. We will still have 6'4 at the bulkhead at the foot of the bed up front. We also played around with the front. Annika was keen to see no step up, she wanted the deck to simply rise up on the slope. And a happy wife means a happy life so this is the design we went for.
The chamfer along the deck level also looked really good with a 75mm height at the bow fading away to match the existing deck at the back of the new cabin top. The addition of the chamfer allowed the bow to be higher and hence the blending of the cabin top and new height was made easier.
We were really pleased with the final design, except it came with a blue hull (better for design work I am sure) but we wanted a silver hull so I had a play on Photoshop and added the bowsprit and added the Ocean Crusaders logo and then Annika and I spent the next few days ogling over the image. We were so happy with it. The next step was to have AAYD send the files to Gurit who would engineer the design for us, just like they did with the original boat.
Gurit are based in New Zealand and we had contacted them previously to discuss our boat and with the fact they had bio-resins and a core material made from recycled PET, we had come to a minor sponsorship agreement with them. However little did we know that the move to go with GURIT would be the best move we made in this entire project.
A few emails went back and forth and then one day we had a video conference where I was on the boat and could show them what we were dealing with. The top had been removed so I could show them where we had to mix the new deck into the old hull, how the stanchions looked and how the shroud bases looked etc.
They then weaved their magic and started sending through designs. The concept of using their HI-PANEL's was floated and we quickly adopted that strategy as it meant we didn't have to create a massive mould and then rely on our skills to create a deck shape over that. Instead the boat would come in 'Ikea' style kit form. The compromise is that we wouldn't have a perfectly domed cabin top, it would be made from three panels and hence have minor ridges, however with our option to cover the deck in solar panels, this was not a major issue. The radius on the edges was always going to be strip planked anyway.
To be honest the design hardly changed in appearance. Then we had discussions over materials. Of course we wanted to use the PET core for the entire boat, however it was found that it did not have the structural integrity that we needed for the particular application so we had to revert to PVC core, however internal non structural panels would be PET.
Over a series of chats and emails we slowly came up with the concept including all the details of laminates etc. We would work out how we needed high density core in certain places and more carbon layup etc. For reference, the majority of the deck is PVC80 which means it is 80kg per meter cubed, however where there are blocks or winches etc, this is upped to PVC200. The difference in weight on a small panel is a not a lot, however when you try to push your finger into the foam, you can on the 80, but it is very hard on the 200 to do this. Then the layup would include extra layers of carbon at these points.
By going with the GURIT HI-PANEL option, we would receive our deck in three 9 x 2m panels, resin infused in New Zealand on their massive table. The panels would be CNC cut so we just have to cut the tabs out. Resin infusion is the process where they suck the resin through the materials from one end to the other. It means you end up with the perfect amount of resin and this means best weight to strength ration. But the added bonus is that all the high density foam and extra layers of carbon were added at this process which means that the top deck is actually smooth and hence less fairing will be required at the finishing stage.
I'm not going to say this was a cheap option, however that comes down to how you value your own time. If we created it ourselves, it would take a very long time and we simply don't have those skills that would make it perfect. Time, we certainly have a shortage off if we want to sail in 2021. If you're interested to know more, then visit our facebook page where we are currently putting the deck together.
So there we have it, our foredeck would arrive in kit form, but we still had the back deck to do ourselves. This was going to be a re-core. We would keep the shape and due to budget constraints, we had to do this part ourselves.
In our next issue we will look at our propulsion system and why we chose to go electric.
Our blog is a long way behind the project purely because finding time to write it between our waterway cleaning programs and the build is really hard. To follow more regular updates of our project visit www.Facebook.com/JBirdIII and to follow the efforts of our charity visit oceancrusaders.org
In our last blog we announced that Ocean Crusaders recently won the Queensland Sailing Sustainability Award for our campaign in last years Sydney to Hobart where we conducted a clean up in the Harbour before the race and in the Derwent after the race whilst competing in the race and taking 3rd in division aboard Ocean Crusaders Dodgeball, John Warlow's Beneteau First 40.7. We can now proudly say we also won the Australian Sailing Sustainability Award.
Ocean Crusaders is a charity dedicated to cleaning our oceans. We go places others don't want to, remove rubbish others don't even know is there and we do it for one reason, for our marine life. J-Bird III was destined to be scrapped if we hadn't bought her. Now she is being recycled and given a new life. Our motto for this boat will be 'Zero Emissions, Zero Compromise' as we turn her electric. That doesn't mean we have to compromise on anything in the way of performance!!! We are seeking sponsors for a race program so if you are interested or know someone who is interested in supporting this campaign, please contact us through our website.
NB: Whilst this vessel will be used to promote Ocean Crusaders, the boat is paid for by Annika and I personally. NO funds raised through donations or fundraisers for the charity will go into this project. Sponsors for this project will receive benefits through Ocean Crusaders as we will always promote our charity and those generous supporters with this boat.
Clean Oceans make us all winners!