Sunday, March 9, 2014

Twinkle twinkle

My preferred method of fastening gunwales to a boat, for a few years now, is using a machine crew with a finishing washer on the inside of the boat, into a sex nut (a sort of sunken barrel bolt kind of thing). It's clean and pretty, quick and easy, and it is a cinch to take off the gunwales when somebody wrecks the boat. Here's an example of how they look, on last year's Rio Rojo. Machine screws and finish washers on the inside (orange arrows) and sex nuts on the outside (green arrows). 


Here are currently available finish washers in silicon bronze and brass.


But something has been bugging me about the finish washers. They are made of stamped sheet metal, so the edges dig into the gunwale when they are sufficiently tightened. It cuts the grain of the wood a bit sometimes. And I have looked the world over (well, on the internet) and have yet to find any solid finish washers. They just don't make 'em.


So the solution, I decided, was to make my own. And why make them round when I could have more fun? Step one was to carve a little star out of wood, with a countersunk hole in the middle, and glue a wee nail into it.


Step two was to make eleven more.


Step three: trim the little nails and glue them into a central stick.


There. A stick with twelve stars.


Sand it oh-so-smooth, shellac it a few coats, and get out the foundry materials. I was too busy to photograph pounding my star-stick into a sand mold, but here is the aftermath.


It's been eight months since I took my bronze-casting course and rushed home to build my own foundry. I fired it up at that time and it worked. Now it's time to see if I remembered all the things one has to do to make it work. I guess it's time to wait for the bronze to melt. 
   Check out the cool Nomex suit my friend Day gave me. It might not stop flying 2000° bronze, but at least it won't burst into flame.

 

Wait 'til the bronze has melted into a nice bright yellow pool, clean off the slag, and pour it into the mold.


So far, so good. But did I make the mold right?


It bursts into flame when I open it up. This is actually a good sign. It means there is a bunch of hot bronze in there where it is supposed to be.


To the quenching bucket.


By god it worked perfect.


A bit of cutting, grinding, and polishing and voila. Aren't they adorable?


They look kinda cool in a gunwale scrap. Note the bad case of foundryman's hand.


Only four more pours and I'll have sixty of them, enough for the rehabilitation of my forty-three-year-old dory Cataract. Tuesday afternoon is the plan. Come by and play if you like. Leather shoes, nonflammable clothes, safety glasses. It's the law.

4 comments:

  1. Did you ever find a source for the sex nuts, or are you going to have to make them too? Very cool star washers....

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  2. My buddy Andy and I had to buy 1000 of them to get the manufacturer to make them, so I'm pretty well set. But it did occur to me that I could make some that matched my star washers. It would be way more complicated and time consuming, but as they say, "What's time to a boatman?"

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  3. I have looked myself and no luck - any interest in selling some (like 70 or 80)

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  4. I'd be happy to make them but the amount of labor is insane. The price would be far higher than the value of the product. They were a labor of love I am afraid.

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