Daspletosaurus Assembly: Building a Frightful Lizard

There is actually a very good reason why I haven't updated this blog in a while: We've been up to our armpits in the lab building the prototype cast copy of Pete III, our 11m Daspletosaurus.

Ilium cast fresh in the mold

Progress is going quick by Academic standards, and we hope to finish the cast by early May.

Both feet before assembly

Jacob and I called "dibs" on making this skeleton, since we've been working on the project for 10 years.

We just admired this for a few days

It really is a great thing to see all this hard work finally amount to something tangible

Making the pubis. It is no longer blue

Plus everyone loves a huge tyrannosaur, especially one way more rare than T. rex.

Progress as of a few days ago. Tail is 17 feet (5.2m) long

Stay tuned for some more exciting progress really soon. We're finishing the neck, working out the gastral basket and have a few cervical ribs to go. 

Everyone loves a little tail

Or even a huge one. Just wanted to share some cool pics we took of Pete III's 5.1m long (17 foot) tail. Caudal 1 is missing from this layout (it was still in the pelvis jacket), so add on another 18cm or so.

Not too shabby

Jacob, our living 2m scalebar

The Fossil Brewing Company shirt is apt

Restoring a Brontosaurus

Growing up in the 80's and 90's was a strange time for a dinosaur fan. On one hand there was a plethora of old books in the library on dinosaurs telling us all about Brontosaurus. On the other, we were getting it beat into our heads that Brontosaurus didn't exist, and it's really Apatosaurus. It was all confusing for those few of us that were actually actively interested in these animals. Today Emanuel Tschopp published a paper resurrecting the genus Brontosaurus as valid. Where does this come in? In college I was lucky enough to work on sauropods, but never on the most famous ones. That all changed almost 8 years ago.

Our company was hired to reprepare, restore, remount, mold and cast the "Apatosaurus" specimen on display at the University of Wyoming geological Museum. This massive beast, also known as the "Sheep Creek" specimen after where it was found, was discovered and excavated in 1902 by a Carnegie Museum crew led by the great John Bell Hatcher. The specimen (CM 563) went back to Pittsburgh where it was quickly prepared in an effort to get the beast mounted and on display. Just before the mounting process was to start, an even more complete beast was recovered. Priorities shifted, and the new Apatosaurus went on display. It's still there at the Carnegie, remounted just a few short years ago.

The old mount, a young Brent for scale

CM 563 sat in storage for nearly a half a century until Dr. Samuel Knight from the University of Wyoming arranged for the specimen to be brought to their museum. He spearheaded the effort to restore incomplete bones, fabricate missing ones and get the whole specimen mounted in a current (for then) pose. The tail-dragging pose didn't age well, especially after the "dinosaur renaissance" which re-imagined these animals as more dynamic beasts.

Pubis bones never mounted on the old mount. Old Carnegie numbers still on them

Where do we come in? Director at that time Dr. Brent Breithaupt contacted us as a local (ish) company that could make copies and provide the museum with a revenue stream with the royalties from sales. Sounds pretty straightforward, right? With 100 years of work on a specimen, you know it never is!

before and after pics of the bones. Yes, originals were painted back in the day.

Hardware cloth, plaster and metal rod restoration from 1950's

Once we had everything in the shop we used special techniques to clean the specimen of its coating of paint to reveal several generations of restoration and conservation work. Everything except for the pelvis/sacrum, which was left on its pedestal and molded in place. It was also the set up for an epic April Fool's joke, but that's a story for another time. In any case, we were able to preserve the historic numbering on the specimen (including some possible field numbers), document its condition, and restore the specimen to good as new condition.

Molding the pelvis in situ

We mounted the skeleton back at the museum in nearly the same pose (sauropods are huge, so unless you have a big open building, your options are limited). One major change though was getting that dragging tail off the ground and up in the air. Much better! You can now see cast copies of this specimen in museums across the world. I'm lucky enough to have worked on this historic specimen of Brontosaurus parvus.

Swinging its tail over Big Al.

Ava Restoration Update: March

Reconstruction of the skull started with 40 individual bones

Whether they are big or small, all ceratopsians sure do have a lot of parts. When they are juveniles like our Avaceratops, the lack of fusion in bones makes that even more apparent. For example, the sacrum (the wad of bones that holds up the rear end of the animal) in adults is usually one giant unwieldy piece. In our young animal, it is 26 individual parts, all with some degree of crushing, though not always in the same direction or degree.

Sacral neural spines molded

More of the massive piles of sacral parts

We've finished preparing the specimen and are busy restoring the individual bones to get molded. Restoration is a catch-all phrase that can mean anything from putting a protective layer of consolidant over the surface to sculpting missing bits to molding crushed vertebral centra, casting them, then cutting up the casts to re-inflate them to their appropriate size.

Most of the ribs, many crushed in strange directions

We're even using our trusty 3d scanning and printing equipment again to make precise mirror images of elements we are missing from one side to help complete the skeleton. In the end we'll end up with everything we need for a full sized standing cast skeleton, hopefully by Memorial Day.

Dorsal neural spines. Each one gets a centrum once restored.

Keep watching the updates on this blog for more news and pics of the restoration, molding and mounting project.

Pete III makes progress: Molding a Daspletosaurus

It's been a long time, not only since I updated the blog, but since we've had any news about our big Daspletosaurus specimen that we dug up in 2006. Well, that's changing now.

Original and prototyped bones

This is basically an update on a post from a few months back where I covered the scanning and printing process if the leg. To get the project moving along we picked some of the low hanging fruit: finishing the left leg! Since this leg was almost complete (missing just one phalanx and strangely, metatarsal III) the restoration was pretty straightforward, comprising of just crack filling. The digits were molded in gang molds and we produced a mighty fine block of metatarsals II through IV.

Original leg ready to mold

That block as well as the long bones were molded so that they can be loaded onto our spin casting machine, enabling us to make high-fidelity hollow casts (saves a lot of weight) that we later fill with urethane foam for durability.

Cast copy of the left pes ready for assembly.

This leg should be ready for display in about 10 days, so don't forget to come by the museum to check it out.

Cap'n Chuck Rises: A Teaser

Like many places, progress on various projects here ebbs and flows. Sadly, the Pete III Daspletosaurus restoration project has been temporarily put on hold so we can address more pressing matters. In this case, it's Cap'n Chuck (RMDRC 06-009), a fairly complete and extremely well preserved Platecarpus tympaniticus specimen that I discovered one cold October day in 2006. A recap of the early part of the project can be found by clicking here. Once prepared the specimen sat in drawers in my office for years.

Squalicorax bites on the top of the skull

That's a nice set of ribs

Recently the powers that be have decided that we should restore and mold the skeleton to replace the smaller Platecarpus planifrons skeleton in our cast catalog. Comparing it to the lower chalk mosasaur, Cap'n Chuck has a nearly identical skull length, more gracile lower jaws and wider top of the skull, however its postcranial skeleton is radically different in proportions. Humerei and vertebrae are nearly twice as big. The ribs are surprisingly uncrushed, preserving their original round cross section as well as curvature. In fact they are so well preserved we can even with some degree of certainty determine which ones belong on the left or right side (nearly imossible to do on typically crushed ribs).

Lower jaws, slender and displaying symmetrical tooth replacement

Nearly complete axis showing beefiness

The differences really are amazing. A few years back, Takuya Konishi split Platecarpus planifrons into its own genus: Plesioplatecarpus. I was very skeptical of this split for a long while, but now after comparing the low chalk mosasaur against its upper chalk relative, I'm really beginning to see his point.