The smokestack is one of those components I’ve been putting off, mainly because I didn’t know how I was going to construct it and attach it. The original plans call for a six inch metal duct – the same duct work that’s in the HVAC system of your house. Attached to the top of the duct is a milk strainer.
I don’t know what a milk strainer is, and I’m sure I’ve never seen one. A quick Google search shows some strainers used in the dairy industry. But they’re very expensive, and I couldn’t even find one that was radially symmetrical. But I did find a duct reducer as part of the Google search.
The duct reducer is just a specialized fitting for HVAC ductwork that connects a larger diameter duct to a smaller diameter one. I ordered one from an online source that would attach a ten inch duct to a six inch duct.
The plans called for attaching the duct to the steel drum by cutting some compound curves in a couple of wood blocks. After cutting the blocks twice, I realized I could never get it right. My solution was to cut a pair of half-round shapes from scrap two-by-four blocks so that they fit inside the six-inch duct. I glued these in place using clear silicon at the bottom of the duct piece. Helpful tip: every handyman’s toolbox should include a tube of clear silicone and a roll of duct tape.
Then I inserted four long screws into the blocks of wood and drilled holes in the barrel for the screws to attach. The last step was to install some automotive rubber weatherstripping around the bottom of the duct to create a cleaner look.
Here’s what it looks like: