These are the last four bones from the Iwaki Musuem Tupuxuara specimen I am using as a source. I am making the pelvis from another source. All the other bones (carpals, pteroid, fingers, feet, tail, nails) will have to be invented. I’ll probably diagrams and fossils from other pterosaurs as sources.
The femur is the leg bone that articulates with the pelvis. The tibia is almost as long as the first wing phalanx (it’s the fourth longest bone after the skull, mandible and first wing phalanx). Pterosaurs are tetrapods and as such also have a tibia-fibula pair, but the fibula in some species is not much thicker than a metacarpal bone. And sometimes it’s almost invisible, since it’s usually fused with the tibia. That’s the case with Tupuxuara’s fibula. It’s fused to the tibia from the base, and gradually becomes thinner and thinner as it stretches along the length of the bone.
I started making the bone shafts curling them from 2mm sheets of XPS foam. It took me an hour to do this (I did find foam tubes for sale, but they were either too flexible or made of foam which was not dense enough, so I decided to roll the foam as usual).
Then I used rubber bands to keep the gluing tube in place while I made some adjustments, curving the femur a bit, or widening the base of the tibia.
I attached bits of thicker (3 cm) foam at the ends. When dry I carved the end shapes according to the pictures and and trimmed with a knife and with fire. As usual, I didn’t have views from the bone ends, so I had to do it all from the side views.
The fibula is fused to the tibia, so I made it separately and attached it to the tibia before covering with resin.
These are the tibiae (actually tibia-fibula pairs) and femora for both legs after all the foam work.
After that I added a layer of acrylic resin, let dry for a day, then sanded and stained with coffee powder. This is the final result. Four views of the leg bones.
Here are both bones connected (I am still not 100% sure about connections, so this might be wrong).
And some images of the full skeleton with the leg bones (the unfinished pelvis is there temporarily to hold the femora in place.)