|Project by David||posted 03-24-2008 11:18 PM||1892 views||2 times favorited||7 comments|
Nine layers of 3/4” x 6” wide boards; bent and glued with waterproof glue. Band sawed to form smaller radius on lower edge. Then do it all over again for a second one. I glued on a layer each day as it took quite a bit of force to do more than one and it was like wrestling a snake!
It’s held together with only the glue. No nails or screws. The glue was polyurethane so it got a bit expensive but it’s good! stuff. Of course the cross pieces on the top are screwed on and the framework all screwed together. I faced the 4 pressure treated 4×4 posts with cedar fence material. It’s been out in the winter 3 years now and no indication of any delaminating. I’ll take some more photos and somewhere I have pics of the bending operation if I can find them. I drew it on Autocad (I taught Autocad) but had to manually draw a pattern for the arch. Had to swing a long compass on the floor; put some butcher paper on a sheet of plywood and drew it all out. I bent the lams around a piece of 2 by cut to the curve I wanted. I didn’t compensate for spring back as the results only needed to look good. Just kept adding layers until I had enough then ran it thru the planer ( steering it as it feed thru due to the curve ). I have a 16” Grizzley Bandsaw so cutting the curve was easy but the end pattern was a bear as it took 2 of us: one to steer at the blade and the other on the outboard end walking around according to directions given. The cut was a little rough and needed some clean up work. Belt sander did wonders.
I finally found the photos of the glue up. I started with a 2X12 that had the curve cut in the edge. Not very wide to start bending around but it worked. It is a true arc made with a very long stick for a compass. The radius was something like 7 or 8 feet. I designed it in autocadd but still had to lay it out.
First day I bent only two and let them cure overnight. I used polyurethane glue. Each layer is a true 1 inch thick: not 3/4” or 1 1/2”. Every day I glued on a new layer and clamped it. When I finally got so thick that the hand screws wouldn’t reach, I layed it down and went to the bar clamps.