Grandpa Webb's blog

Monday, 02 December 2013

One thing not to do with polystyrene packing

Hanging from the ceiling of my garage is a large white model plane.  It can fly, but it only makes one flight at a time because every time it lands, it breaks.

Let me explain. Along with many of my age group I hate wasting stuff. As a child I used to make toy tanks from an old cotton reel, a bit of candle, a rubber band and a matchstick. With the rubber band fully wound, my tanks would climb a small slope. They were much admired at primary school.

Grandpa WebbNot long ago a courier delivered to our house a fragile item that was protected by a vast amount of expanded polystyrene – the white stuff that weighs nothing. It was mostly in sheets about an inch thick, with the occasional length about four inches square.

“What are we going to do with all this polystyrene?” I asked grandma.

“It goes in the black bin,” she said, waving at our row of environmentally-correct dustbins.

It seemed a shame to chuck away so much raw material. Surely it could be used for something. How about making a plane for the grandsons? It’s so light it’s bound to fly, and with so much polystyrene, I can make a really big one.  

I would need some glue. Polystyrene melts away if you try to stick it with a glue containing solvents, so I made a trip to the model shop to get some special stuff, designed for the job.

I marked out the wings, tail and fuselage, and began to carve them into shape with a kitchen knife. It’s just as well I did this in the garden as polystyrene peelings have a mind of their own. They are either charged with so much static electricity that they stick to you, or fly away at the slightest breath of wind. I decided to do all the cutting over the black bin. Even so, when I finished, the area around it looked like it had a light covering of snow.

One thing not to do with polystyrene packingWhen you fashion an aeroplane with a kitchen knife, you end up with an object that looks like something from The Flintstones. The rough-carved wings, fuselage and tail really needed sanding. Sandpaper doesn’t make polystyrene smooth, but at least after a rub down with a sheet of 60 grit, the shape was better than before. The finished plane has a wingspan of 5ft 6in, which is bigger than any of my grandchildren, is ridiculously light, but with a few old bolts in the nose for balance, it actually flies.

Next time the grandsons visited, the plane was unveiled and taken to the sports field down the road.  Carefully launched into the wind by the six year-old, the wings bowed upwards as they provided lift, and it flew for about 20 yards before nose-diving gently into the grass. As it landed the fuselage broke in half.

We had found the reason why people don’t make things from polystyrene. The stuff they use for packing has no strength whatsoever; the slightest load will break it. The grandsons were disappointed for about 10 seconds, and then turned their attention to trying to climb up a rugby post.  

Like the early aviators, I’m back at the drawing board. I’ve been to the model shop again and bought some very thin balsa wood with which I intend to wallpaper the fuselage. Hopefully this outer skin will stiffen the structure and make it possible to have perhaps two flights next time before the thing breaks. I will also need to stiffen up the wings because they will have to carry a slightly heavier fuselage. Work has already started on this.

I’m optimistic that the Polystyrene Peril will fly again. Who knows, if it works, maybe I can strap a small electric motor and propeller on it and a radio control unit.

Mind you, that might be a bit too difficult for the grandchildren to fly.

Never mind, they could have another go at climbing the rugby post while I fly it.

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