In the past, I have tended to work on one project at a time. This is not only because it's hard for me to keep several balls in the air at once, but also because it seemed like a logical way to do things. Recently, however, I seem to have been working on a variety of tasks, but with all the deckbeams fitted aft, I could prepare to install the tabernacle. This needed to be done concurrently with the forward deck beam in the forecabin, because the tabernacle is not quite what David envisaged, nor in the same place as originally planned, so measurements from the design could only help me so far. Indeed, the only two things that really counted were that the after face of the tabernacle should be at station 2, and that it should end up at an angle of 4°.
Another matter to take into consideration is that I had no design for a mast step, the solid and secure woodwork that will stop the tabernacle from moving to the left, when the mast wants to move right and vice versa. With no rigging, the step has to be immovable. Normally, one would build up a large box and that would be that, but in my case I had a fore and aft backbone, surmounted by the side of the bunk, and an athwartships floor, backed up by a floor for the keelbolts.
It seemed to me that the obvious thing to do was to utilise the purpleheart floor to build up the mast step. As I still have some purpleheart left, I cut this to shape and stuck it to the floor, in two layers, leaving space to access the keelbolt nut. (In theory. It would be a hell of a job to get a socket there and use it, in practice!) As the floor had been left coated in epoxy, it was a simple task to sand it down and slather some more around. I put on one layer and then decided to build up the step to 100 mm, so stuck on another layer.
While the glue was going off, I carried on fitting the deck stringers, which will help in fitting the plywood deck, inside and out.
In the meantime, I sweated blood over a pattern of the base of the tabernacle, so that I could make the mast step the correct size. As the tabernacle is tapered and was over length, this took a ludicrous amount of measuring and cutting: pattern making is not my strong suit. And, tell it not in Gath, but the base of the tabernacle was not absolutely square.
I placed the pattern on the bottom of the boat alongside the bunk and started building up the step against the hull. This obviously had to be pretty strong - 12mm of plywood on its own is not going to resist much sideways movement. However, Arne Kverneland, a Norwegian member of the JRA, who has been involved in numerous junk rig conversions, has evolved an excellent method of making a mast step - simply gluing layers of plywood together until you have the requisite height and shape. This is a lot easier than taking a 100mm block of wood and trying to fit it to the complex shape of the hull.
Eight layers later, and I had a good, strong step alongside the hull, spreading the loads from hull to floor to backbone. Great stuff, epoxy.
Back on the deck framing, I fitted intermediate stringers. More framing makes for a stronger deck and ensures that the thin plywood lining will follow the intended shape. I am using treated kaihikatea for this: a very light, New Zealand wood. It soaks up resin like a sponge, so you have to take your time over gluing it together, to avoid dry joints.
And now, for the first of the two satisfying achievements mentioned in the title: I finally fitted a porthole! Doesn't it look great? Admittedly, I haven't yet set it on mastic: until I have roughed out the saloon, I'm not entirely sure that when it's open, hinged up, it will be away from my head, so I might have to turn it 90°. But as I'd got it all polished and perfect, I didn't want to leave it around where it might get damaged.
With the after part of the tabernacle sorted out, I turned my attention to the port side. Again I cut purpleheart to shape and laminated it in place, this time straight to the 24mm bottom of the boat. Both purpleheart floors have had holes drilled in them, through which coachscrews will be wound to help secure the tabernacle. I am fairly sure that, considering that it is also going to be glued in place, it isn't going to go anywhere! At least I hope not.
I had spent quite a lot of time debating whether to make a sloping step or to cut the rake onto the foot of the mast. In the end I decided that it was better to have a level base to glue to, so that the glue wouldn't run off while we were faffing around getting the tabernacle into place. With the help of trigonometry, I had worked out that I needed to start 11.7mm from the horizontal with my saw cut. You can imagine how many times I checked to ensure that the tabernacle would end up leaning forward, rather than aft. It was a bit scary, in truth. And hard work, too - it was too big to fit under the drop saw.
I was ready to do a dry run, and as Pete had his boat hauled out here, Marcus was around and, coincidentally Rob and Maren had called by for a visit, I took the opportunity of doing so. For a while there was, perhaps, an excess of chiefs who all knew what I should be doing next, but we got it standing,
slipped in the piece of plywood, on which I had marked the 4° angle,
lined it up,
and clamped it into place.
Then we took careful measurements to the front of the cabin
At the same time, I drove the coach screws part way into the tabernacle, so that I could drill the holes for them, in the right place.
Then we took it out again and everyone went home.
The next job was to cut the notches for the beam and to glue it into place. I clamped a stick of wood in place to ensure that the forward face of the beam was 516mm from the forward beam, as we had measured.
The next day, I was ready for the second satisfying achievement: finally gluing the tabernacle into place. About time, you might say: it's been kicking around for about a year, now!
Having had a dry run, and only having to put glue on the butt of the tabernacle, getting it into place was quite straightforward. Pete and Marcus did the heavy work and with the beam in place to lean against, there wasn't too much stress, although I did start fretting that the epoxy would be going off when we realised that the trim along the top of the bunk was stopping the tabernacle from being quite vertical.
That was trimmed off and I got down to cranking in the coach screws.
With those in place, we could be sure that the tabernacle would stay solid until the glue cured. I was pleased that Pete could be here to see his contribution to SibLim taken to its conclusion.
After that, I had only one beam left to secure. I have had to take the forehatch into account here. Putting it on the centreline, as tradition and dogma demands didn't make much sense: there will be reinforcing running fore and aft from the tabernacle, and I don't want to cut a damn great hole through that. For that matter, the forehatch could well interfere with the rigging for the sail. It will go over the head of my bunk, so that I can look out of it at night. As I don't intend to put sails in and out of it while underway, and as it will be dogged in anything but the calmest of conditions, I cannot see that it should be a problem.
I thought it about time to have an overview of the boat. It's starting to look something like now, with deck framing and the tabernacle in place. I have to decide what colour to paint said tabernacle - it's pretty big and I'm not sure I want it to stand out too much!
Now I can complete the cabin sole in the forecabin, covering it in tigerwood. A job I'm looking forward to.
Marcus had just been given a ute from an old friend, and when he brought it back, it was loaded with second-hand kauri that Gordy had contributed for Marcus's boat and mine. Thank you Gordy: what a fantastic gift. Now I should have sufficient kauri to finish the job. There's plenty of work in cleaning it up, but you can see from the piece on the right hand side, that it's well worth the effort.
4 comments:
Another milestone complete, thats a really substantial tabernacle and they need to be.
Are those lockers really deep or are you really that small? More power to your elbow!
Both really. There is a huge (frightening!) amount of space under the bunk and I would - just - qualify as a hobbit. (I know - I was here when they were recruiting.)
What is huge, here, halfway around the world, in Atlanta, Georgia, USA, where I live, is respect for what you have accomplished in all your voyaging, and are now accomplishing there in building your next boat! Thanks so much for blogging!
Hi Chris. Thank you so much for your kind words. It's nice to know that people enjoy sharing these experiences with me.
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