Good technique for bending cedar shingles
I’m applying #1 cedar shingles to the exterior of my house and I have few bays that popout about 16″. The convex angle there is about 20 degrees, and I want to bend the shingles. The old previous shingles were done that way and it looked pretty good so I want to repeat the same detail. I’ve already done some of the bending, it looks great, but it’s sort of ‘hit or miss’. (A lot of times the shingles break) It seems what is necessary is to select shingles that are a bit more flexible than others (there is some variation), and then soak them in water for awhile. I’ve also tried scoring the back a bit; not sure if that really does anything.
Has anyone tried any techniques that work fairly reliably for doing this? I’m using standard #1 red cedar shingles. Thanks for any pointers.
Replies
You could try making yourself a steam box.
http://www.lulu.com/items/volume_1/55000/55471/1/print/55471.pdf
Steam bending
is the best way, although it is somewhat time consuming and a little bit trial-and-error.
Get some chunks of 6x12 that are about 18" long. Lay out the curve you want right down the middle of one of the 12" sides, leaving as much material on both sides of the line as possible (i.e. divide the piece so that both halves weigh about the same). Cut them on the bandsaw to make clamping forms. Make 4 sets. Make the curve a little tighter than you really need, to account for spring-back.
Get yourself a propane burner and a galvanized trash can. Put some rocks the size of baseballs in the bottom of the can. add water up to the top of the rocks, and put 16 shingles in there, skinny ends down. Steam them for maybe 20 minutes. Take out four shingles, arrange them in opposite directions (thick/thin/thick/thin), and clamp them tightly between the two halves of the 6x12. You need strong clamps to really squeeze them.
Every time you take out four shingles, put four more in, keeping track of what is what. By the time you get all four clamping forms done the first one will be ready to open and re-use.
Oh yeah... cut the shingles down to 6" wide or less, or else make yourself some BIG forms if you want to bend the wide shingles. For the job I did, I used shingles in the 3-6" range, which was fine for the little cupola they were installed on.
And of course, don't let the garbage can burn dry.
By the way...
that cupola has a nice pointy finial on it
I seem to remember an article in FHB or JLC recently. Think it was on a sloped roof. Good article. Google it.
"I've also tried scoring the
"I've also tried scoring the back a bit; not sure if that really does anything."
it shortens the lifespan
Wet them by soaking in how water for a day before