Friday, October 30, 2009

TV Chair Adventures -- Part 1

I need a special chair for my living room. My kids have both outgrown the teeny little wooden rocker they used to use to watch TV, as well as their cute little plastic chairs, and now they keep fighting over who gets to sit in MY favorite chair. My lovely tie-dyed couch is too far away from the TV for their viewing pleasure. Rather than all-out war, it's time to find a new solution.

I have some pretty specific requirements, since floor space is at a premium in my living room. After all, we have lots of bins of stuff, plus a consistent Wii-Fit user who wants enough space for the yoga mat and push-ups. So the new chair has to have a fairly small footprint. Also, I want a back for comfy TV watching, but the back and seat have to be fairly low so that anyone sitting on the tie-dyed couch behind it will still be able to see the TV. A "gamer's chair" would be a little too low--old people like me need to be able to get up from the chair. I searched for "low chair" on the Web, and I found some I'd love, but most of the ones I really liked were in the $2000 range (and while she may think she's worth it, do I really want Lacey taking over a $2000 chair?)!

My older daughter and I came up with a design that would fit the requirements without breaking the bank, and it would be uniquely ours.

Really Big Toilet Paper Tubes

It is possible to get really large heavy cardboard tubes that are used in construction work for pouring concrete posts and columns. Use "cardboard concrete form" as your search criteria. There are various makers such as Sonotube, Quikcrete, and Sakrete, but many contractors simply refer to them as Sonotube (similar to using the word "Kleenex" to refer to any type of facial tissue--bad for protecting brand trademarks, but everyone knows what you want). The big chain hardware stores (Home Depot, OSH) carry them in stock in up to 12 inches in diameter, but for the bigger ones (18, 24, 30, 36 inches in diameter), you need to go to a construction contractors' supply store. Here in the San Francisco Bay Area, I got some at Peninsula Building Materials Co. I got a 30-inch-long piece of 18-inch-diameter Sonotube there for USD $25.95 including tax ($9.50 per foot). I later got a 4-foot-long Quickcrete 12-inch-diameter tube at the local OSH for the matching ottoman.

Regular Old Toilet Paper Tubes

The kids and I spent a fun hour or two cutting up our large collection of used-up cardboard toilet paper tubes to make chair models.


After lots of time and discussion, we decided on the basic pattern to use for the chair (something in between the three middle models in the back row above).

We also did a fair amount of "design by comparison", where we sat in our existing chairs and measured how we fit in those chairs and where the contours were that made the chair comfortable or not.



We decided to make the seat platform about 12 inches from the floor. I made a full-size paper pattern to model the chair.


The pattern would later fit around the Sonotube so I could trace it for cutting.

Cutting the Sonotube

The large-diameter tubes such as my 18-inch-diameter tube are very thick (around 1/4-inch thick) cardboard (not corrugated), and they are quite hard to cut. I tried a number of (non-powered) things, but what worked the best for me was to use a utility knife (box cutter) to just stab through the cardboard. Later, for trimming edges and fine tuning, I would cut along my line as deeply as possible, peel off a layer of cardboard from the discarded side of the line, cut along the line again, peel off another layer, and so on, until I could finally cut directly through what was left.

I bought two pre-cut plywood circles (Closetmaid brand) that were 17.75 inches in diameter. I planned to use one inside the bottom edge to protect the Sonotube and the other as the seat platform.


While I was at the Peninsula Building Materials Co., I also bought a roll of Deck-o-foam, used for expansion joints in concrete, to cover the outside of the Sonotube. It's actually the same type of foam I used in my origami patterns, though a different shape (4 inches wide, half-an-inch thick, and 50-feet long for USD $20) and not rescued from a packing box.


I used the same FastBond 30 glue I currently use for making my sandals (I still have a lot left of the gallon I bought!).


I covered the entire outside surface of the tube with the Deck-o-foam.


Now I've got the basic structure of my chair.