For years now I've thought and taught that glue should be a back up for already solid joints. It's a belt and suspenders approach. But there has always been a nagging curiosity as to how a chair would hold up without the glue.
So as I went about finishing up a chair that I started during my demonstrations in Rochester, I figured, why not give it a go. And even without knowing the long term results, I have already realized some benefits of the attempt.
In making the joints, I use air dried mortises and kiln dried tenons so that the joint benefits from the swelling of the tenons as the moisture contents equalize.
When I started to put this chair together without the glue, I found my focus on the fit of the joints slightly elevated. Not profoundly, but I suppose that driving the joints all the way home without the glue made for a different experience. The ring that wood on wood joints make when seated is very gratifying.
There is also that little space that generally has to be allotted for the thickness of the glue film, but in this case, I went for the absolute tightest joint that I could manage without blowing out the mortise.
As I turn my attention to the top of the chair, I am thinking a great deal about the joints where the short spindles pass through the thin continuous arm. Without the glue, I am definitely going to make each one a sort of "hammer eye" joint by having a subtle shoulder on the spindle so the arm can't shift down and flaring the top of the mortise so that the wedge will spread the spindle enough so that arm cannot move up.
It may seem like a silly esoteric exercise, but I am thoroughly intrigued as I think and rethink each of the joints and what it takes to count on them without glue. Of course, time will tell which joints loosen, and it will be fun to live with it, watch and learn. I think I'll paint it blue.