Thursday, November 12, 2015

A day in the life of a Daspletosaurus bone

Some people asked me not too long ago about what we do in order to get some of these bones ready for molding. In the case of Pete III, our Daspletosaurus from Montana, the condition of the bone gave us some additional problems. All specimens of course get excavated and painstakingly prepared by our expert staff, but in Pete III's case, even the prep necessitated the invention of new techniques which I published on a few years back. The entire specimen was pixelated, with some bones made up of hundreds of thousands of fragments. Lots of glue was needed to even expose the bone, which is huge, literally Tyrannosaurus rex sized. Once done the left ilium looked kind of like this:

Next up is reconstruction of any major missing bits and holes with epoxy putty like Aves Apoxie Sculpt. That's the grey stuff.

We then apply a barrier layer of B-72 to hold everything together for the next steps. Shiny!

Then we take our gorgeous bone and smear the whole thing with tinted Hydrocal.

 Yuck. OK now it doesn't even look like a fossil. Never fear, most of it will be gone soon. The main aim is to work the Hydrocal into all the seriously tiny cracks in the surface to better hold the bone together. This also reduces the amount of the relief in the specimen so molding goes much faster. The excess on the surface is removed with air abrasion.

Doesn't look so shiny anymore, but we can fix that with a wee bit more of very thin B-72.

And there you have it, one half of a bone restored in a few days time. Now we just make a support jacket so the entire thing can be flipped over and the process repeated.