Friday, April 8, 2011

Bus Blog 25: Off with its Head

One of the definitive elements of a rocket stove is that the fire takes place just inside the opening of the stove.  This forces the air around the fuel to compress and move faster as in the venturi effect.  This air delivers more oxygen, faster to the fuel creating the conditions necessary for it to burn fully so less, almost no, soot and creosote are carried with the smoke and deposited on chimney walls.  This is why it is possible to run 20 feet of exhaust pipe through your house to harvest heat without worrying about high levels of maintenance.  Rocket stoves are built to burn fuel effectively and clean, so a lot more is possible with them, than, say, a salvaged wood stove.

Sometimes we only learn if it's the hard way.

My first, the lazy, solution was to try and unclog the chimney, so I slid across the icy roof of the bus on knees, removed the chimney cap and attempted to wriggle a drain snake to the bottom in order to attach a wire brush and pull it through.  No luck, the snake would go in a couple of feet and stop, too many kinks in the pipe.  I tried jamming sticks in, pencil rod, beating the chimney with a hammer, even swearing at it didn't help.  The more I thought about it, if I was able to clear the choked chimney, wouldn't I just be fixing a symptom and not the actual problem?  Wouldn't I just have to unclog it again?

"Screw it," I thought, "Off with its head."

Kirstin, none too please with the idea of metal dust coating the new interior of her bus made sure I surround the stove with a wall of tarps.  It looked like a really frustrating kids' fort.  The plan was to pull the whole chimney out and install a replacement made of single wall stove pipe but after seeing how well the bit of pipe that went through the roof had protected the surrounding area from heat, I decided to chop off the bottom and link the replacement to it. The thing was solid anyway and would make a good anchor for the thinner pipe I intended to install.

The chimney came apart in a shower of sparks and was hauled outside.  It was full of creosote.  Jesus, what was I thinking?  I was thinking it was a rocket stove, that's what.

Of course, no one in town had a replacement pipe for my stove and anything that was close, that I could make work with a couple of adapters and a lot of luck, was ridiculously expensive.  I made a lot of phone calls, saw a lot of web pages.  Of course, only when I went to the auto parts store to see if I could order exhaust pipe to cut and weld in, the guy at the parts counter asked, "Did you check Ribtor?"

Ribtor Warehouse is located in SE Calgary, just outside Inglewood in a big tan building.  Remember the last scene in Raiders of the Lost Ark?  The one where the ark is being shuffled off to some corner of a giant warehouse amongst thousands of crates and boxes?  Imagine all those boxes open and you pretty much have an image of Ribtor.  There are aisles upon aisles and shelves upon shelves of all manner or dusty military surplus, industrial equipment with ancient factory grease coatings, uncharacteristically colorful camping gear, utilitarian cookware and all manner of miscellany.

Of course they had the stove pipes I needed.  Of course when I approached the register they guy at the counter said, "Five bucks."  I didn't know why I hadn't thought of it myself, I'd only been visiting the place monthly for the past four years.  Oh well.

Back at the bus, the installation was quick and painless.  The pipes were joined and the whole works was sealed.  We were ready for a test.

With crossed fingers, I lit a piece of cardboard that sat under a pile of kindling.  A moment later I added a few large pieces of wood.  As the fire burned, the front and back doors started to work again, the floor warmed.  Soon enough, the bus was hot, I stripped to a tank top and shorts.  I smiled and looked through the windows as people outside, bundled against the cold, hurried past.

I once heard someone say that the quickest way to learn to make good decisions is to make a lot of bad decisions, you either learn what went wrong real fast and fix it, or give up.  I haven't heard many truer things said.