Saturday, April 28, 2012

Model: The Camella Chair

This next prototype is a papasan style chair though is slightly different. Papasan chairs are generally made of bamboo or wicker and come in two pieces, the stand and the chair. This chair will be slightly more rigid than a regular papasan chair and will have an adjustable top section to allow people to either use the chair in the same way as a papasan chair or to sit atop the chair legs folded.

The idea behind this chair comes from 2 sources that work well together. The first being that I have always quite enjoyed sitting on the floor which probably stems from my love of Lego. As a kid I remember spilling a huge box of Lego out on the sitting room and taking over an entire corner, playing happily for many hours while sitting on the floor. The second source comes from zazen or zen meditation something I occasionally do. Zazen is not like other forms of meditation where you sit and chant or imagine you're floating on a cloud or any of that sort of thing. Zazen roughly means "just sitting" and all you do is sit and stare at a wall and think about nothing for a while.

So lets get started... I was fortunate enough to find a small hobby shop quite near to me with some modelling tools which I will be using for this prototype. One of which was a semi circular compressed chipboard bowl. That (you would think) will make the whole thing a bit quicker. I also got the same compressed material in board form for constructing the legs. I shall be using my trusty Leatherman for the woodwork. I also found the German version of all purpose glue (Alleskleber in case you need to know) made here by UHU. I've used this glue for model making many times before in versions by Bostik and Radex (I believe it's Ardex in the US) with great success.

Ok so lets get started. I start by cutting out the blanks for the leg pieces from the chipboard. So far so good.

Agasp! A model-making injury. Fortunately, like the many thousands of other minor injuries I've recieved from model-making over the years, this one is not fatal.

Next I cut the curves of the side legs with a combination of the Leatherman saw and rough file. Now, while I have unwavering belief in this tool and it's ability to fix or build anything from an airfix model to a house I could have probably sped this process up a bit with a junior hacksaw. You live, you learn, you buy a hacksaw with next months pay.


Ok so now for a change of pace I moved onto the bowl section of the chair. For the prototype I came up with a fairly simple mechanism to create the movement I wanted in the chair. For an actual production chair it would be a lot different as would the legs. Sketches later, for now fitting a piece of chipboard to a bowl with a flattened bottom and curved sides.

Shaping this piece to fit took an inordinately long time and a lot of fidgeting with files though I'm fairly pleased with the tightness of the fit. the smaller strut was added for rigidity.

Now back to the legs. Again there was a great deal of shaving slicing and cursing involved as I fit the legs to the curvature of the bowl. two t-shaped bars were added to separate and support the legs and also to limit the ammount of travel of the bowl section.

And then to combine the two. I was fairly pleased with the profile and movement of the chair though I would probably make the legs less tall to bring the chair closer to the ground. As I said earlier this chair is intended to facilitate both lounging (when tilted) and sitting cross legged (when flat). While I very much enjoy sitting on the floor the cold, hard laminate in my apartment and my bum are slightly incompatible.

This shows how the bowl strut fits nicely into the t-bar for the angled seating position.

And this shows the floating position of the bar in the flat position.

The next morning was one of the first sunny days of the year... time for a few beauty shots. first again the two positions of the internal strut.

And some rather lovely sunlit shots of the chair in action.

While I was pleased with the result, this prototype did point out to me a few things of note for a production version. Firstly while the planar symmetry of the legs does lend a nice profile to the sides they are a bit close together. The problem with this, as can be seen above, that in the reclined position the legs of the chair might interfere with the foot room of the user. Two solutions to this could be to either widen the span of the legs (which would also help in lowering the profile of the chair) or possibly to build the legs in a triangular arrangement. This might be a better solution than widening the legs. Essentially the legs could splay from the rear to the front with an open end on the front side where your feet rest. This would create more foot room at that side and would still maintain symmetry. Also a 3 legged arrangement gives more stability on uneven ground.

In a future blog I will post some computer modelling of this chair with those options explored a bit further.


John O'Shea 2012

No comments: