After cutting the seat to shape using using the help of ticking sticks, I rasped the rim of the seat until I could wedge it inside the trunk and get it level. I usually use a 6” spirit level for this task, but I left it at home. So I used the bubble level in my combination square – a first!
Then I traced the shape of the seat on the inside of the tree trunk, both along the top of the seat and below the seat. This gave me two lines indicating the location of the seat. I decided to secure the seat using eight 5/8” maple dowels left over from another project. The plan was to drive them through the trunk and into the seat. Here’s how I did that.
I chucked a long 5/8” auger into a corded drill and drilled eight holes through the trunk. I began drilling the holes from inside the trunk and took pains not to splinter out the exit hole. Then I wedged the seat in place and used a 5/8” spade bit (with an extension) to drill into the seat from the outside of trunk, going as deep as I dared.
Then I drove the maple dowels in place. No glue. I cut them to length so about 3/8” sticks out. If this solution doesn’t work I want to be able to pull the dowels out; 3/8” is enough to get ahold of with pliers.
Then I turned the chair over (more easily written than done) and added a few steel L-brackets, fastening the underside of the seat to the tree trunk. (Every wacko project needs a few L-brackets.) Note that the steel screws in the photo will be replaced with brass as soon as I can get to the hardware store.
Then I turned the chair back over and gave it a sit.
It sits quite well. This is no surprise because I used the same angles I use for other chairs. The difference was I had to adjust the angles on this chair with a chainsaw. The only thing I couldn’t really address was lumbar support. The inside of the tree trunk curves away right where I would rather it curve inward. A good bolster pillow should remedy that.
Now comes the fun part: Detailing the chair, applying the oil finish and adding a few pieces of flair that my wife, Lucy, and I have dreamed up. And then onto something a bit more serious.
— Christopher Schwarz