The hipped roof on the WP tower turned out to be a pain to make. I'd started by making a substructure out of 0.060 sheet and adding 0.020 pieces on top for the roof shape, but found that the roof wasn't coming out square and even. The first roof went straight in the garbage, and I wasn't looking forward to making the second. "Wait a sec... didn't I think I could make the form for a hipped roof like this with the 3d printer?
Makerbot. It took a couple tries - printing a square base upped the odds that the print nozzle could catch on excess plastic when doing large, filled areas - but printing a new version in the shape of an eight pointed star printed just fine. With a bit of filing (seen here) to square things up and get rid of little blobs of plastic, I was ready for second try at the roof.
An hour later, I had a perfectly pyramidal roof covered with Builders in Scale simulated tarpaper. I'd been frustrated by the first roof that didn't work, so the 3d printer let me make progress and move on to the fragile railing and stairway that'll make the model special.