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.

Sunday 11 May 2014

More bulkheads, mast step doublers and centerboard stuff

I'm gradually working my way backwards in a reasonably methodical way.

The next logical step after bulkhead 3 was to do bulkhead 4. I deviated from plan again, making it from a single piece of 9mm ply that goes the full width of the boat. I wanted the area around the front of the centerboard case and back of the mast step as strong as possible. To do that I knocked up a couple of doublers for either side of the spine between bulkheads 3 and 4, and added tabs to the front of them that pass through bulkhead 4 and into the front of the centerboard case. This will stop the centerboard case pivoting with respect to the mast step.

Here's the detail of the join. It holds together nicely even without epoxy. I'm hoping once it's epoxied and filleted it'll be nice and strong. I'm thinking perhaps adding some unidirectional carbon tape along bulkhead 4 once things are together could also be helpful, as bulkhead 4 transfers loads from the shrouds to the centerboard and mast step, so we want it to be as stiff and strong as possible.

Bulkhead 5 is almost to plan. The only deviation is to make the side seat 20mm taller and 20mm less wide. That gives a bit more space for centerboard case stuff, and reducing the width of the seat gives me a touch more room in the cockpit - think putting a sleeping bag on the floor and sleeping in the boat. I'm thinking I might make a removable slat floor to facilitate this without getting soggy, but that's a long way down the track. Incidentally my 12.7mm trim bit makes short work of duplicating pieces - just make one then run round it to make another. Alas bulkhead 5 can't support itself until I do the floor, so for now it's just neatly packed away.

I also made the arms for bulkhead 3, again using the trim bit to duplicate. This led me to find my first stuff-up. I'd got the measurements wrong on bulkhead 3, so one vertex was out by a good 5mm. After vacillating for a little while, I just cut a new piece from 6mm ply. Took less time to actually do the work than umming and ahhing about what I was going to do. I'm sure I'll be able to recycle the old piece into other things.

I cut the side pieces for the centerboard case from 6mm ply. The rest of the centerboard case will be made from "Tasmanisn oak", which I'm told is neither Tasmanian nor oak. Indeed I believe it's also known as Victorian alpine ash, which is Victorian but isn't ash, being a eucalyptus. Anyway, it's a good middle-of-the road hardwood. reasonably strong and durable, but without the weight of jarrah, and with nice straight grain. It's readily available locally in lengths to 3m. I'm thinking this will be my go-to hardwood for the boat. I'll use it for stringers, keel plank, keelson, etc.

So here's what the spine is looking like now, assembled as best I can without actually gluing anything together (I'm waiting on my first shipment of epoxy - what is it with boat supply places taking forever to fill orders?). The astute can see my first go at bulkhead 3 leaning against the wall in the background, and the rapidly growing pile of offcuts.

Last job for the weekend is to laminate the timber for the centerboard itself. I'm using western red cedar for the majority of the centerboard, with the leading edge made from jarrah. I'm told they used jarrah for the young endeavour, which is plenty strong. In any case it's the toughest timber I know of, and I'm sure it'll help protect the centerboard from dings when I run it into rocks etc. The western red cedar is incredibly light, I'm hoping it'll be reasonably easy to shape. Once it's shaped I plan to sheath the whole thing in unidirectional carbon to give it stiffness, strength, and impact resistance.

So after two weekends and a few evening's work, I reckon I'm up to 30 hours.

Sunday 4 May 2014

Starting on bulkheads

Our cat Mogget is fascinated by the whole woodworking gig. He likes to be involved as much as possible, except when I turn the vacuum cleaner on. He gets quite enthusiastic at times, to the point of rolling in the wood shavings.

Here he is supervising cutting of some of the lightening holes in the spine. I'm using a circle jig on my router to do this, as it's of a size where that's doable.

I built the 6mm bits of bulkheads 1, 2, and 3, and slotted them into place on the spine. Here's bulkheads 1 and 2 on the spine. You can also see my lovely little home-brew speakers in the background, playing lots of really crappy eighties music:

Then I went to work on doublers. John's plan is very economical with plywood. The doublers are all made from multiple pieces, so you can make use of offcuts wherever possible. I decided that was fiddly, so I'm wasting plywood with impunity. Hence the doubler on bulkhead 1. The process I've settled on is to cut everything oversize by about 4-5mm with the jigsaw, then use the router to finish the cut. When it's a straight line I can use some timber to cut against. Ditto when it's a circle of appropriate size for my circle jig. Often it isn't though, so I just work these bits by hand with the router.

I'm not sure Mogget agrees with my wastage of ply.

Here's a close up of bulkhead 2 with it's doubler on top. The bulkhead itself is 6mm ply, the doubler is 9mm. The doubler is quite light.

It certainly becomes three dimensional quickly.

And one quick view of the model, this time showing the whole lot so far:

Thursday 1 May 2014

The spine

On Wednesday I decided there was no way I could afford to do this (at least in a decent time scale) if I had to pay for freight for ply. So we borrowed a trailer and went to Bunnings, and bought four sheets - two of 9mm and two of 6mm. I have no idea what their ply is made from, except that it's stamped "BS1088" and had a brochure talking about sustainable forestry. On close inspection it looks pretty good. The face sheets are clear and I couldn't see any voide around the periphery of the sheets. It'll do. While we were there I picked up a pile of western red cedar planks that I'll laminate to make the centerboard.

So once I got home, I cleared the bikes and car from the garage, got Perry's help to put a 9mm sheet on the bench, and marked out the spine on it. Then I cut that out with a jigsaw, and repeated the exercise twice to make doublers for the front section. Then I clamped the three bits of ply together and worked them with my trim router (think tiny cuts) and sandpaper in a block until I was happy with the curves, and all three pieces matched nicely.

Here's what I'm trying to make, from my model. The spine is a good spot to start, because it's a manageable size, but a fair bit of the boat (bulkheads 1 through 3) hangs off it, so I can construct a largish subassembly that then gets attached to the rest of the boat before having to permanently banish the car from the garage:

Here's a pic just before picking up the jigsaw:

And here's the result of about four hour's work. I still have to cut the holes in the back of the spine, and slot it to accept bulkhead 3:

As I work I come up with things that I'm missing. The top two items at the moment are a decent plane and a spokeshave. It's very nice to actually be making things though.

Oh, and I've come up with a name for my boat. It'll be Elena.