Educating Risa

Daegan found this video recently:

He’s watched it several times, and wanted to try it at home. He drew the instructions, and made a list of supplies to get (plaster of Paris from Michaels, and play sand from Canadian Tire; we had everything else):

 

They began by putting sand in a large plastic bowl, and smoothing it out:

The first T rex skeleton Gareth chose was too large for the bowl, so he ran up to his room to get another. It was small enough that the triceratops skeleton Daegan chose could also fit in the bowl. They pressed the skeletons in lightly:

They then used a squirt bottle to lightly mist the impressions left in the sand, helping the sand stick together in this shape:

They then pressed the skeletons in a second time, ensuring that all parts of the body would be visible:

Then it was time to mix the plaster, in the ratio 2 parts plaster of Paris to 1 part water. Jim bought the giant economy size bucket of plaster, as we both expect we’ll be using it again with our palaeo-crazy boys.

Then it was time to pour it onto the fossil impressions in the sand:

We discovered that we made the plaster too thick; it ‘globbed’ rather than poured:

But no worries—daddy to the rescue! Jim scraped the remaining plaster out and them smoothed it over the sand using a craft (popsicle) stick. Just like icing a cake!

We’ve set it aside to dry overnight. Looking forward to seeing the results tomorrow!

BTW, if you try this at home, in addition to making the plaster a bit thinner, Jim also recommends putting a thin layer of vaseline on the side of the bowl just above the level of the sand. It’s going to be interesting getting our fossil out in one piece tomorrow. But hey—that’s science. Trial and error, learning from mistakes, etc.