Ribcage v.2 - expanding foam

I'm currently attempting to make a second ribcage. This still needs to have some rigidity, but it needs to be flexible enough to be opened up and light enough to suspend from the ceiling. Over the last two days I've been experimenting with applying expanding foam to a wire frame.

The product I've linked to is not what I've actually been using; I went with B&Q's own-brand version because it was cheaper. (For some reason this isn't on their website though.) Basically, you spray it and it inflates as it dries. It's intended to fill gaps in walls, but I was trying to use it as a construction short-cut. The idea was that I would be spray it on in roughly the right shape and then I could carve off the excess.

I started by wrapping a mannequin in cling-film, (so the foam didn't end up stuck to it), and then constructing a ribcage using a light, flexible wire. I left a gap down the centre of the sternum so I could cut straight through the foam there and open the ribcage in order to lift it off the dummy.

Great plan, but the foam proved a lot less tractable to work with than I had anticipated. Gravity was my biggest problem. Eventually I managed to make a person-shaped meringue.




It was all a terrible, poisonous-smelling mess. However, it did come off the dummy beautifully, and after some carving was starting to look more like a ribcage.



It still needs work. I think this might prove to be an annoyingly time-consuming stepping stone to a better version. It isn't working for me at the moment, but I'm not completely sure how to fix it just yet.