Friday 28 January 2011

Latex (not the writing software) and how the first attempt failed.

To model the papier mache around the styrofoam ball and yet have some clearance we require something that is very elastic and fits tight. Andrew Downie suggested (industrial) latex, which, as it turns out, was a great idea. It's not easy to fit anything around a sphere without folds, but with enough force, anything is possible:

Put the latex over the ball, grab it at the bottom and twist it until there are no folds anymore. This is easier said that done, but with a bit of trial and error it should be doable. The clamp helped keeping it in position, but you will need patience: it can be VERY frustrating to place the clamp without un-twisting the latex (there is a lot of torque!). Everytime that happens you have to start all  over again.

Take the papier mache and model it around the half-sphere. Easy enough. Or so I thought. To give it even more stability, I gave it some PVA icing, like this:

While the PVA dried, the papier mache underneath didn't, not even a bit despite an electric fan pointing at it for hours. The effect: after two days it was still pretty soft.

To contain the mistake I made, I tried to peel off the layer of PVA:
Which again, wasn't a great idea, the papier mache layer was very thin now and, to my surprise, still wouldn't dry on the inside. When I took it off (take the ball out first, then carefully tear out the latex), it came apart.

That was the sad end of my first attempt.

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