That is why I said for future reference for anyone who might be reading this, the rest of us are out of luck that don't happen to have a super smart mechanical engineer for a DadLooking at a metal conductivity chart, silver, copper, gold and pure aluminum are the best conductors in that order. Not satisfied with speaker connectors available commercially, most are gold plated, only a few microns thick. I tried to find solid copper connectors, could not find them anywhere. My dad is a mechanical engineer who is basically a mad scientist. I asked him if he knew where to get solid copper bolts. He asked what size and how long I needed them and he made them for me. They are made out of oxygen free copper. They are 5/16 bolts that are long enough for the triple walled subwoofer cabinet.
I wanted to try the allthread as an experiment. I've never seen it done before and wanted to see if it worked. I think there are pros and cons to each bracing method.Great looking box.
Out of curiosity, what made you choose to go with all thread for bracing?
As a mechanical engineer myself, I think using strips of wood would be more cost effective and easier to use.