Saturday, January 9, 2010
The practical cold-weather shop
It was January 1, 2005 when I started building my Bolger Birdwatcher. While my wife and teenage children slumbered away the New Year's revelries of the night before, I went out to my shop and started laying out the pieces for the four frames that run down the hull like spinal disks. I had the radio playing while I worked, and reports came over the Canadian Broadcasting Corporation network in the aftermath of The Indian Ocean Earthquake of Boxing Day, 2004. The death toll mounted with every news break -- 4,000 became 40,000, became 90,000. The number would climb to 230,000 souls eventually. The spicy smell of the mahogany boards being cut filled the shop and reminded me of journeys I'd made in the tropics. I thought how absurdly lucky I was to be building a boat in a safe, warm room at my northerly latitude while families, villages were being destroyed somewhere over the horizon.
My backyard shop was not big enough in which to build the whole boat. The plan was to start with the smaller bits -- frames, rudder & tiller, centreboard assembly, etc. -- while I looked for space to rent. This is a standard procedure for building an airplane, and I would recommend it to anyone. You get your feet wet at minimal cost in materials and time, make progress and build confidence a step at time. When the fiddly bits are needed, they are ready to install. However, it may well be that you don't like boat building after all, or that your free time is not what you hoped. You can always sell or donate small, finished pieces to the next builder and feel good about it. But a half-done hull is usually doomed to rot.
Via classifieds, I found a large two-car garage to rent not too far away. I spent (ie. wasted) a lot of hours going to and from that shop, and nothing would have sped up my building more than having a place to work a few feet from my house. But I didn't. The rented place had smoothly operating, powered overhead doors, enough electrical outlets, and an even concrete floor. It had been used for car repairs, so I spent a day cleaning it up and taking a load of old parts to the metal recycler. One of the orphaned items was a large green upholstered chair, which some builders call a weeping chair or thinking chair. I got to know mine well, on both counts.
The shop was nearly 28 feet deep inside, which seemed ample for a 24 foot boat. However, it was just barely enough. I had not considered that curved assemblies, like gunwales, are longer than the actual boat they adorn. I was lucky that all the parts for the Birdwatcher could be laid out straight within the walls I had rented.
The shop was unheated but well insulated, important when you live at 53 degrees north latitude and the winter temperature can dip to -40 C, and is typically -20 C most nights (ie. below zero Farenheit). Indeed, I would say my most pertinent advice for building relates to coping with cold temperatures, something that the literature of boat building does not address. A cold shop in Maine or the Pacific Northwest would be warm by my Canadian prairie standards.
I bought an inexpensive ($150) kerosene heater with blower and large fuel tank, and plugged it into a thermostat unit I put into a surface-mount electrical box and hung from a nail. The rig could heat that large shop to a comfortable working temperature in under 15 minutes, but it fouled the air badly. Because the shop was so well insulated, I found that I could run the shop up to temperature and a little beyond, then open one or both doors briefly to freshen the air. I also kept three 500 watt halogen work lights running. I needed the light, and their waste heat kept the kero heater from cycling on too often. But when it was bitter cold outside, it got harder to balance warmth and fresh air.
If I did it over again, I would buy a heat-exchanger type construction heater, and temporarily rig up a proper vent to the exterior using an entry door opening if I could not cut a hole in the wall. It would cost about five times the price of a portable heater, but you could sell it afterward. Buying jugs of kero was a hassle; it was expensive and local shops ran out. Well, there are many routes to good shop heat. Regardless, I think you need to be able to achieve 15 C (60 F) easily, whether you are working under tree in Florida, or in your Helly Hansen woolies and Sorel boots in my neck of the woods.
Boat-building typically requires the glueing up of very long pieces -- gunwales, chine logs, and planks. I found that a narrow, temporary shelf built along a wall was a great place to scarf together long items. You could clamp or screw work into position, and things would stay out of the way of other jobs while the glue set up. Set-up generally requires room temperatures for 24 hours. Rather than keep the entire shop heated for that long, I found that glue joints could be kept warm by aiming a 500-watt work light up at the shelf from below, and trapping the heat with a stack of insulation batts over the workpiece. You have to be very careful of fire risk with powerful lights -- especially, don't use extension cords for this technique. By careful positioning and some tests with a household thermometer under my "glueing blanket," I could keep glue joints at room temperature overnight even if the rest of the shop was colder than charity.
That about does it for the description of my shop set up, seen in the picture. The hull of a boat comes together quickly, and by the end of January I thought I would be ready to launch come spring.