Click here for a Flickr show. There is a sketch of the anchoring of the tie deep into the leg and a sequence of photos showing the execution. I shaped the tip of a large screwdriver to accurately seat a brass insert deep inside the hole, at the middle level of three concentrically drilled diameters, the smallest of which is at the bottom and allows the threaded rod to over run when it is inserted. The smallest diameter also provides a shoulder against which the brass insert stops. The middle diameter is sized for the insert to screw into, and the upper largest diameter allows clearance for the insert to drop down to the beginning of the middle diameter, and also provides clearance for the screw driver.
There are also several photos of the bottom half of the chair assembled to test fit the cross ties. (You may notice little pieces of wood in the middles of the arches that resemble keystones. They are simply there to protect what will be smooth arches from being marred by the clamps.) This is the first time I have seen this much together, and is the first confirmation that all of my geometry works and that all of my joinery and metal connections are correct. Whew! I think about 400 hours have gone into this project (including all the figuring out of things, building jigs, testing, creating mock-ups, remaking parts, and a lot of research and self teaching of general woodworking techniques.) Still, I am relieved that it all worked and I am now, for the first time, confident to proceed to glue up the chair!
By the way, I think it looks amazing.
I used to live in New York City. I designed homes for the tycoons of Wall Street; Park Avenue, Scarsdale, Greenwich. It was great fun. And, after years of saving up for a down payment, I was just about to buy my own little place in Fleetwood, half an hour north of the city, when the economy fell apart. Architects are like canaries in a coal mine when the economy slows, and true to form, there were massive layoffs in firms all over the country. Devastation of the profession. So, I decided to try to find something else to do for a while. I bought a 23' school bus and I'm on the road to see if I can figure out what that might be.