Tuesday 29 July 2014

Buying expensive tools and bling, getting on top of sharpening, and gradual progress.

One regret I have is not cutting the notches for the stringers and bulkheads in the bulkheads while they were still flat on the bench. When they're mounted to the spine and floor they're really very floppy, and it's quite difficult to get them to stay still to cut them. Luckily, my frustration at this job coincided with getting a huge pile of money back from the tax man (one of the few perks I get from living half the year in the middle of nowhere is that I can claim a "remote area tax rebate" come tax time, which is quite generous). So I bought things that would help in boat building with my windfall.

First one is a lovely little Veritas crosscut saw, which cuts through the ply very easily and makes a lovely cut. Here it is having just cut the inner gunwale notch on bulkhead 4.

I also bought supplies (only half of which have arrived thus far) for sharpening my tools. I figured a 300 grit, 1200 grit and 6000 grit Japanese waterstone would do the job, along with a flat steel plate for dressing. Alas only the 300 grit stone and plate showed up, so after some thought I dug out some aluminium oxide and cerium oxide grit I had left over from making a telescope mirror (long story) and had a play.

I find that if I'm patient and methodical, and work tools with the 300 grit stone, then the 25um, 15um, 9um aluminium oxide on the plate, then strop with an old belt loaded up with cerium oxide, I get a blade that I can see my own reflection in and that's sharp enough to do surgery with. When that blade meets a bit of timber, it just cuts through it like it's butter.

A few wipes on the 300 grit stone then five minutes with 25um and 15um aluminium oxide gets me most of the way there in a tiny fraction of the time. No reflection, alas, but I can still make lovely cuts easily. It'll be interesting to see how the 1200 and 6000 grit waterstones compare.

While blowing money, I also splurged on some bronze. I bought rowlocks and some cleats, just because they were shiny. I may have stuffed up a bit with the rowlocks though. These are ones that fold over so they're below the gunwale. I had it in mind that they go on the outer gunwale and fold onto the outside of the boat, but all the pictures I've seen since buying them show them mounted to the inner gunwale of a boat without a deck and folding down inside. Hmmm. I figure I can either just stick them on the outside and be damned (it is after all my boat), put them on the inside of the coaming, or just build a whole extra boat around them with no deck, and buy some more conventional (not to mention cheaper) deck mount ones for this boat. Anyway, they're plenty shiny, but I can see how to make them much shinier.

Meanwhile I continue to cut pieces of wood up and glue them to other pieces. I've epoxied the floor ply to the keel plank (making the whole thing now too heavy to lift) and added the lower cockpit seat stringers, plus both sides of bulkhead 5. I've also started cutting notches in all the bulkheads for the inner gunwale. I figure once all the bulkheads are mounted I'll put the inner gunwale in next, which will give everything much needed stiffness and make the job of cutting notches a lot easier.

Monday 7 July 2014

Garboard plank and building frame

We went and bought some more sheets of ply. I rearranged things in the garage a bit, and cut a 10:1 scarf into four sheets with my no. 5 plane. Another big workout. With all this boatbuilding, I'm going to end up with an upper body like Schwartznegger. Although it's hard work, scarfing is actually pretty simple. With ply the layers of wood guide you.

Next step was to build a building frame for the boat. This was just knocked together with framing pine. It took a while to find two lengths that were acceptably straight for the side pieces. before the boat went on I used the building frame as a huge workbench to prep the double length scarfed garboard plank.mMogget sees it as a huge cat climbing frame.

Here's another view of the frame. Don't look too closely at it. It's rather rough. It's flat and square though, and nice and strong with six legs being braced in all directions.

So here's where the fun really begins. I marked up the garboard plank with John's offsets, used a stringer to draw a fair curve, and cut it out with a jigsaw, finishing with my plane to get a really nice smooth curve.

Then I cut a hole in the middle for the centerboard slot, and offered up the rest of the boat. Much grunting ensued with this two-person lift. It took three tries before the centerboard slot was just the right size. To celebrate having somewhere to put my motorbike again, I tidied up the garage a little.

Next step is to put the proper reference height pieces in at each of the stations to form the curvature of the bottom of the hull, then glue and screw the garboard plank to the keel plank. Then I'll add more bulkheads and install some stringers and seats.