You got here from there?

 

It wasn’t exactly a straight line, but there really was a path from the plywood prototype to the finished piece. I started by transferring the rocker and seat locations and curves from the prototype (see the previous post) to a piece of foamcore that a neighbor had discarded (1/4” plywood is my usual choice, but the foamcore was there).

It wasn’t anything fancy; I setthe prototype down on its side on the foamcore and traced the rockers, then pulled a side off so I could transfer over the seat and back profiles. I had an overall concept of the piece with its branching components, and I played around for a few hours filling in the details until I had a basic sketch to work with. A good eraser really helped with this!

 Full-scale sketch based on the comfort prototype

Full-scale sketch based on the comfort prototype

I then spent some time bandsawing rough parts out of some left-over 12/4 and some plywood, then screwed things together with drywall screws. A rough prototype emerged (I didn’t add rockers), but it gave me a chance to see if what I envisioned was going to work at all.

It also gave me a sense of whether I could create the front/back shapes that I wanted if I kept going down this path. It wasn’t exactly pretty, and an awful lot was missing and/or wrong, but it was encouraging enough to want to move ahead.

 The first '3-D sketch'

The first '3-D sketch'

My goal at this stage of any design is to figure out the important questions, and then to answer them as well (and as quickly) as I can. I had answered the most important question: ‘did this idea have some potential?’  Now came the tougher issues of refining the very rough visual elements and how to actually build this thing. I decided to laminate up the main components out of 1/8” bending ply. That meant building lamination forms. I took the curves off of my sketch and made up the four main bending forms: for the rockers, the rear legs, the arm supports, and – for lack of a better description – the front legs. Laminating the bending ply was easy. I added the front profile to the rear legs, but I left the front legs and arm support wide – I knew I was going to need to play with those.

And then I stopped. And thought. And thought some more. About the branching joint. I knew what I wanted, but this was going to require a very solid joint and some serious experimentation.

Next post: experiments in three-way lap joints.

Jeff Miller