Boats and more boats
Over the Christmas holiday, I visited with my friend Lyons and we worked on his boat, a Townie that he bought last year and has been gradually restoring. We’d tried to bend in some frames a week earlier, but were blocked by a couple of problems: the steamer box didn’t have a good enough source of steam and the ribbands were too thin. It took hours to get the box up to 200 degrees using a tea kettle and a pressure cooker as steam sources. Once we got the ribs good and hot, we bent them into the boat. However, since the ribbands were too thin, the ribs ended up deforming them. So, back to the drawing board.
We spent the rest of that day putting in much thicker ribbands and over the week, Lyons worked out a far better steam source. Here’s what he came up with after doing a little research.
What we’ve got here is a double walled stove pipe. At the bottom of the stove pipe is the burner from a hot air balloon and it’s connected to a propane tank. It blasts heat up through the inner pipe. Air is drawn down through the space between the inner and outer pipes. In the inner pipe is a length of copper tubing that’s coiled from the bottom to the top of the pipe.
You hook up the lower end of the pipe to a hose, let water trickle in and by the time it gets up to the top of the tube it’s pure high pressure steam. At first we used garden hose to move the steam into the house, but the end melted from the heat.
A section of radiator hose from the auto shop fixed it right up. This thing kicks butt. The hose connects up to the steam box inside the basement.
It got the steambox temperature up to 200 in no time at all.
The only problem was that the frames we were using just couldn’t handle the stresses of the kind of bend we were asking them to do, and even after a good steaming, they all broke. We think it was a combination of the frame material being pretty dry, and using the wrong kind of wood. Next option, re-cut the frames out of oak.
Still, he’s got the best steam generator you can build at home.
January 22nd, 2007 at 9:00 am
Last weekend I bent in all the full-length ribs milled from green oak I got from Cowls Lumber (Amherst, MA) just around the corner. Tom had suggested green oak after all of the black locust ribs cracked when we tried to steam and bend them into place. Yesterday we steamed and bent in all the 1/2-length ribs. The green oak was docile and submissive. We only broke two long ones and one short, major success!
My 1926 vintage Winabout sloop (Town Class prototype made by the Pert Lowell co., Inc., Parker River, Newbury, MA http://www.pertlowell.com/) now has all its new ribs! The next adventure will be planking. I’ll start with new cedar garboards and wedges, and move on to see how much of the original planking can be salvaged for re-use…
Many warm thanks to Tom who helped me work out the kinks in my backyard/basement steaming operation, who engineered a replacement set of ribands for my wimpy ones, who was not too discouraged by the pop-pop-pop of the black locust ribs, and who suggested a marvelous final solution (green oak). Thanks also to my wife Laura, and several of our neighbors (Alan, Simon and JohnF) who all pitched in at critical moments of bending, clamping and applying zip-ties to the ribs. I can’t wait to go sailing with all of you!