Sunday, 25 May 2014

Restoring tools and making sausages

Two very different topics this week. Alas I've been out bush for much of the last fortnight, plus my epoxy is yet to arrive (buying stuff from boat supply places + shipping to Geraldton = much time waiting for stuff to show up).

So the first topic - restoring tools. Years ago I had a lovely old Stanley Bailey 4 plane. Very much standard issue, reasonably good quality, small enough to use one-handed but with enough heft to remove serious amounts of timber. I lent it to a mate and then promptly moved across the country, so it's his now. My centerboard is going to need plenty of planing (as are lots of other things on the boat), so I went looking for a new plane. I ended up buying a number 4 from ebay - probably older than I am, with proper rosewood handle and tote. Looked pretty well loved in the photos.

So once it arrived, I spent an enjoyable weekend restoring it. The handle and tote were rubbed back and got a few coats of varnish, showing the grain wonderfully. The blade, which was well rounded over, got a patient sharpening on my hone. For good measure, I went at the sole and sides with the hone as well, to remove some of the corrosion and scratches. If you're ever wanting to flatten your hone, spend a few minutes working the base of a plane on it - it'll very quickly become flat. Once much of the corrosion and scratches were taken out, I put a piece of 400 grit wet and dry on a flat countertop (okay, my kitchen bench) and polished the sole up so it's beautifully flat.

The result looks lovely, and is a delight to use, just like a plane should be. Of course now I've clicked buy on a number 5, and am eyeing number 7's...

Next onto the sausages.

I've decided I want a weighted centerboard. Not massively heavy, just enough weight that I won't need an uphaul. I figure around 5 kilograms of lead will overcome the buoyancy of the board and ensure it sinks nicely, without ending up a pain to work with. So I went to Bunnings to buy lead flashing. Turns out the stuff is revoltingly expensive. They wanted around $60 for a 5 kilogram sheet of lead flashing.

So I figured it'd be cool to recycle a battery for the lead. I've got a never ending supply of dead batteries, so I grabbed a ten kilo one and went to work. This is where everything turned to custard.

Turns out lead acid batteries are mostly lead oxide, which is completely useless. I opened the case relatively easily, and then neautralised the acid with sodium hydroxide until it was neutral and safe. Then I extracted the electrodes. Inside a battery is the most disgusting, filthy black mess you've ever seen. Most of the electrodes are lead oxide paste, held in a skimpy mesh of lead, with lead interconnects. Getting the lead oxide paste separated from the lead mesh was really no fun. Never again - my marriage just won't sustain the aggravation. Once done I had a paltry two kilograms of useable lead, for about four hours of the most disgusting work I've ever done. And now I've got about 8 kilograms of lead oxide that I have no idea what to do with.

So rather than waste my time and sanity on more batteries, I caved in, went to Bunnings and bought a 3 kilogram sheet of flashing. This at least was relatively pure lead. I melted my 5 kilograms of lead in a crucible (aka old camping billy), skimmed the oxides off the top, and poured the lead into a mold, which I made by pressing a sheet of ply the right size into some beach sand.

More disappointment. The mess that came out of the mold was about the right size, but was icky and porous, with a very rough surface finish. Not very flash. I figured the only way forward was to work with what I had, peen the surface to press the mess together, and melt more lead into the worst of the holes using a blowtorch. Then more peening to get it to something resembling the right size and shape. Thankfully lead is super ductile, so puts up with this abuse.

So this is the result, after about twelve hours of pure, unadulterated frustration and cursing:

It's not going to win any awards, but it's about the right weight, and about the right dimensions to fit into the cavity I've made in my centerboard. There are no photos of the process because, like making sausages, it's best left unseen. Now I truly understand why people aren't keen on weighted centerboards.


Joel Bergen said...

Hi Suzy,
Are you sure 5 kilos will be enough lead? The Navigator plans call for a 100x100x60 brick which would weigh 6.81 kilos. I added about 10% more than that to mine just to be safe and even with all that it sinks rather slowly.

Suzy said...

Hi Joel,

Now you've made me panic. The answer is yes, I'm pretty sure. 5kg should be plenty. My centerboard has both less chord (~300mm vs ~400mm) and is thinner (NACA 10011 profive vs NACA 10015).

So my my (very rough) calculations, I end up with about 70% of the volume of the standard centerboard. So my 5kg og lead is equivalent to about 7kg in the standard board...