A Burning Man Blog by Mike

Here is a mock up using wood of a K-Hinge with a zipper sewn in. This is the closed position. This allows the hinged joint to be folded over on itself when unzipped or to stiffen the hinged joint when zipped together. Leaning on this prototype with many pounds of force showed that it held together well. Surely the foam board would have broken with so much stress applied to it. Since the glue and canvas are in shear during the stress test, then only the thread and zipper’s cloth are the only weak spots. You can see the one corner of canvas where I peeled it up to see how well the glue held up. The glue bond is much stronger than the bond that the aluminum foil has to the paper on the foam board.

This is the open or folded position. Leaving a couple of inches of zipper hanging off of the end, makes it easy to start the zipper when assembling the Yurt.

There is the end view of the K-Hinge and the zipper. I’ll try and sew the gap between boards a little tighter when I build the foam board versions.

We stood the assembled wall and roof panel up against the garage wall. The tip of the roof panel was set to 8 feet high. This duplicates the roof angle of a fully assembled Yurt. So now, we are looking at how to adjoin the next wall/roof assembly to the one we just made. I worked out an idea yesterday. Today I have to find the materials and make up a test section. The idea is to sew on half of a heavy duty zipper to one roof panel and the other half of the zipper to the other roof panel. The zipper will have to be sewn to the canvas before it’s glued to the foam board. A few inches of zipper will have to be free hanging in order to be able to start the zipper each time. Each seam where a zipper will go it about 54 inches long. So a 60 inch long zipper should work fine. The sewn zipper should have enough tensile strength as the tape it is replacing.

There are two zipper joints that have to be tested. One is with a K-Hinge installed as occurs between the upper and lower roof panels. The second zipper joint will occur between two unattached roof panels. This second joint will have half of a zipper attached to each of the canvas end caps that are glued along the edges of the roof panels.

I’ll find a couple pieces of wood and attach them together with a K-Hinge with a zipper sewn in as well. This way I can stress the joint to see how the zipper will fail.

Tonight Bill and I did the assembly of the toughest K-Hinge yet. The wall panel and an entire roof panel. It was way more stressful than it was real work. It came out fine. I came up with a simple jig that held both panels upright while we layed the canvas up against the drying glue. That jig was a great deal of help. I’ll let the glue dry all night and see how it all folds together tomorrow. If we like this prototype, then we get to build 5 more!!

Here is the jig. Just a pir of 2×2’s sitting against the garage door opening. That’s literally it!!

Here’s the front view of the jig with just a wall panel and a cured K-Hinge done days ago.

The roof panel is layed out on a table ready for glue to be applied. The height of the table saves wear and tear on the back.

Just like magic it’s done. Too many hands were needed to take any pics.

When the hinge hits up against the 2×2’s it just takes a little tug on the canvas to pull it straight. It takes 2 people pushing on each side of the canvas to push it tightly against the glue.

All done!!