Tuesday, September 4, 2007

Main hull battens mounted

Yesterday I was able to get the aft half of the hull battens mounted. First task was to mount stringers along the outside of the form frames, to ensure each one was plumb. The two frames for the aft cabin roof were not very cooperative, probably due to an existing bend\warp in the plywood, and had to be assisted with some braces:

(the clamp you see above is holding a spirit level to the frame)

Eventually all of the frames were plumb with temporary outside stringers mounted:

Then I started on the battens. I started at the aft end of the hull, because the curves looked easier and the only battens I had on hand were my pine sticks from the float construction. This went pretty quickly:

I went ahead and battened the aft cabin roof frames, because I think I have enough room to foam and laminate that entire area in one operation. I don't have the same confidence for the main cabin roof, so that will be done separately.

Today my first job was a run to the lumber store, for more batten material. Being a chicken regarding some of the curves up by the bow, I decided to splurge on the good stuff (clear cedar) this time. (For you local folks: Martin's Lumber and Hardware in Everett (on Broadway Ave) may look like a run-of-the-mill operation from the outside, but appearances are deceiving - they have an excellent selection of clear cedar, fir, hardwoods, etc, in super-long lengths too (eg, today I bought 1"x3"x14' battens - they also had 16' and 18' lengths). A wooden boat builder told me to try them out several years ago, and I've gone there ever since.) Getting the cedar was a good decision, it was much easier to work with (no knots to fight with, and less splitting) and it bent into shape really nicely. I wish I had spent the money for this stuff from the beginning.

Andrew had arranged to come over today to help watch and work, and he showed up shortly after I got back with the lumber. Working together, we made short work of getting the forward hull battens mounted from the keel to the top of the gunwale:

I put a lot of extra battens in the gunwale area, because I anticipate using that area as a walkway (with some thin plywood to help distribute the weight) when laminating the main cabin roof.

At this point, I'm now ready to start laying the foam planks. I've decided to use 10" wide planks (I went with 8" on the floats). After briefly messing around with the heat gun on the first plank, Andrew and I decided to take a shot at making a hot box for heating the foam planks. I scribbled down a design and then we made a quick trip to the hardware store for electrical items and some more wood. This is what our initial attempt looked like:

It's quite rudimentary, but the bulbs did light up! :-) When we tried to heat up a foam plank though, it never did get warm enough to be super-pliable. Looking at Rod's fixture, this could be because my bulbs are not close enough together. I can't put any more in though, eight 250W bulbs is all my 20 amp circuit seems to be able to handle. Andrew and I next tried reducing the vertical distance between the bulbs (moving the bulbs 4" closer to the foam), but this didn't seem to help much. My next attempt will be to staple some reflective insulation material to the outsides of the rack, to see if the generated heat (there is a lot of heat for sure - you can feel it when standing next to the lamps) can be more contained.

Anyway it was a fun day -- Andrew, thanks again for coming over and helping.

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