Bringing the frame up

Raising of the ribs

The first rib to be raised was the tenth one (the big one with the big floor, wich is meant to become a bulkhead). As I mention before, the dead wood was meant to help locate and positon precisely the ribs, the tenth rib was to be welded against the forward compartement on the deadwood. The first few ribs were held in position by some welded angle iron framing fasten to the beams running under the keel.


We took great care lining up the ribs. With NC cutting our days it is possible to get accurate rib shape and if positioned right there should be no reason the ribs couldn’t dictate accurately the shape of the hull. Once more, the computer model made it easy. We worked with the laptop in the truck parked beside the boat, pulling out any notch to notch dimension we needed to line up the frames. Each rib was tied to the other and had an external temporarily welded frame to support it until enough of the boats longitudinals would lock everything together. Putting up the ribs was a very stimulating phase of the boat building, it was fast and provided much visual progress, the temperature was cool and dry. Even thoutgh my nerves were making balls in my stomach, it has been my best boat building time up to now. I had drawn and built all those ribs and was terorised by the idea I may have done a mistake at some point, at the same time there was that huge satisfaction to see it come together as planned.

So we worked every day from sunrise to sun set and with a crew of two people, a dog and five ducks (chickens were too busy being chickens) we had all the ribs up within a week.

Adding the longitudinals to the frame Its funny how a simple question as which longtudinals are we going to install first can bring in a full reflexion. Every step is fully thoutgh and I probably can give a reason for every step, order or detail. Maybe I shouln’t think so much but maybe time lost on reflexions is better than time lost fixing a mistake. All that to say that we started by locking in the deck longitudinals starting by the center. Before it is a full structure the boat frame can get distorded, the idea is to start by adding the structures that add stability without forcing the frame out of shape. The deck longitudinal litteraly dropped in the notches on most of the ribs and would only need a bit of pulling for the rest.

Copy of 20051022_012

The hull longitudinals followed, alternating one on one side and the corresponding longitudinal on the other side to keep forces balanced. Was keeping forces balanced an issue at this point for such a structure? I don’t know, maybe not….but what if it was, it didn’t make it any more trouble to follow an order.20051021_013


The longitudinals went easily in to the notches for most of the boat. The only trouble occurred in the bow where they would trip to much ahead of the second rib for my liking. We solved the problem by chopping the flat bar at the second frame and making new pre-bent pieces for ahead of it. The problem wasn’t worth crying over, it only meant a little bit of extra work. I have since paid a special attention at the longitudinal frames in other steel vessels that I visit or see pictures of and noticed most boats have tripped longitudinals in the bow. Does that mean I shouldn’t of been bothered by a bit of wobble? Maybe, but if I was to design an other hull I would plan ahead for some NC cut stringers for the bow and not even try going against the steels will.


The last lengthwise frame are the deck pipes. It was a charm fitting those in there grooves in the ribs. As each rib met the pipe on a different angle, so each groove would have a different elliptical shape drawn from the intersection of the pipe and the rib on CAD. Once more, it was neat to see the shapes mate as planned. We started from the middle of the boat and went are way to the ends. On this picture I’m trimming the end to match the bow. I’m also secretly enjoying the monkeying in my giant play structure, did I ever climb, swing, balance…play in the frame. It can’t only be work. This picture also shows the break between the stringers and the new bow longitudinal.


After three weeks of framing, we got something that really recalls a boat. Better than that it looks like the cad model. I don’t know how many times and why I got so surprised how the real thing matched the drawings. …maybe a little bit of lack of confidence…


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