Introduction: Adaptive Wood Chair

About: I am a teacher researcher in mechanics and product design. I am also a manager of a web agency.

In this project, I wanted to make an adaptive wood chair inspired by the Tripp Trapp chair. I used for that some basic tools like: circular saw, circular sander, electric screwdriver and jigsaw. My design is little more "angular" than the original, and my be less confortable, but it's cheaper !

In first, I made a quick 3d modeling in only one part (no assembly, it's faster!). With that modeling, I had an overview of the project, I could choose all the components I have to buy.

Step 1:

I bought material for two chairs, the cashier made a mistake, in fact I have around € 80 for that (I have 2 childrens)

  • 2 cleats 20 x 10 mm x 2m (FR : tasseaux)
  • 2 round aluminum tube 8 mm x 2m (FR : tube rond)
  • 2 steel threaded rod 8 mm x 1m ( FR : tige filetée )
  • 1 steel threaded rod 10 mm x 1m
  • 1 plywood sheet 10 mm (FR : contreplaqué)
  • 2 crude plank fir 30 x 150 mm x 2 m (FR : planche sapin brut)
  • 10 blind nut 10 mm (FR : écrous borgne)
  • 200 screw 3 x 25 mm (FR : vis)
  • 1 furniture oil (FR : huile meuble)

Missing on my list above :

  • 6 blind nut 8 mm
  • 6 washers M8
  • 4 wood screw 4,5 mm x 80 mm
  • 10 washers M10
  • wood glue
  • adjustable pliers (FR : serre joint)
  • circular sander disk 40, 80, 120

Step 2:

I make M10 screw with threaded rod, it's really cheaper! I cut it with an electric disk cutter ("disqueuse" in french). Must tighten the nuts on the threaded rod before cutting it. By unscrewing the nuts , it straightens nets. The nuts will be easier to screw after.

Crude plank are twice cheaper, but you have tu sand them. I Cut in length the 2 crude plank fir, sand them with a sand disc of 40 in first.

Screw cleats are quite longer, cut them in first, then drill them. Use a free cleat to make the gap between two cleats (top left on picture). When all cleats are screwed, cut them with circular saw.