Well I survived my first post, so I thought I would start a thread of my first (digitally) documented project. I do have WIP photos of some of my older stuff but it's all on film and I don't have a scanner. You can watch over my shoulder as I work on my 'rex. My aim is to make an accurate, poseable Tyrannosaurus skeleton out of cheap, safe and simple materials (cardboard, wire, wood, papier mache) using simple tools and techniques. We'll see how this goes. If you have any questions, feel free to ask; I have no secrets.
Apart from having always liked Tyrannosaurus rex, I've got several other inspirations for this project. One of them is this:
This 1/6 animatronic T.rex skeleton was created by Hall Train Studios for the American Museum of Natural History and is now part of a travelling dinosaur exhibit. I've only ever seen it on video, never in the flesh (or bone, as the case may be). I just think this is soooo cool.
Another spur to action has been the work of this man, who does amazing wood carvings of dinosaur skulls and skeletons in 1/10 scale;
I'm using FMNH PR2081, the specimen known as "Sue", which is part of the collection of Chicago's Field Museum of Natual History, as my prototype. I'm going to be using Sue's dimensions and proportions to size up my rex. The Journal of Vertebrate Paleontology's Memoir on T.rex osteology by Christopher Brochu is my main source of information.
I have begun with the tail. The photos below show the steps in making the tail vertebrae. The larger ones consist of four parts, centre-line, centrum ends and transverse processes. This results in a cardboard "sketch" of each vertebra. When I have completed the rest of the vertebrae done to this level I will go back and fill in the spaces and bulk them out to the full volume of the bones
Last edited by Thagomizer; September 22nd, 2010 at 03:05 PM.
Reason: Changing thread image
Different parts of the skeleton, different bone forms, call for different approaches. The vertebrae, fiddly little shapes that they are, will have to be more or less individually sculpted by hand over the basic cardboard forms I built in the previous installment. The pelvic and pectoral girdles include large plate-like bones with some curvature, the ilia and the scapulocoracoids. For these structures I've decided to make masters in cardboard and plasticine, then make simple,one-piece open plaster molds of these masters from which to cast papier mache parts.
Starting with a side view of the scapulocoracoid and a front view of the articulated pelvic girdle, I map out the edge of the bone by finding key landmarks in each view and measuring how far each of these points around the edge lies from the sagital plane of the body, the front to back centre line of the body. This results in a wavy line graphing the contour of the bone edge's movement away from and towards the body centre line. Bilateral symmetry means that I only have to do this excercise once; the opposite side is just a mirror image of the first. The wavy line graph is going to be used as the wall of an oddly shaped box, the floor of which is the side view of the bone. The side view is glued to thick cardboard; the wavy graph bit is printed or glued onto thin card, folded and bent around the edge of the side view piece. The resulting box is then filled with plasticine or clay. The bone itself is then sculpted on top of the box full o' plasticine. Because I am using plaster for my mold material, I avoid any undercuts so that I will be able to remove my papier mache parts without their breaking. A similar procedure of measurement, box construction and filling is used to produce forms for the ilia.
I took no photos of the plastering bit, so the next pictures will be of the finished plaster molds for the ilia and scapulocoracoids. (Kinda like those cooking shows where they break for commercial and they come back on with the dish cooked and ready to eat.)
I have to say this is very interesting I'm looking forward to seeing it take shape. Looks like some seriously painstaiking work.
I know this isn't strictly speaking related it's still quite interesting. After looking at the animatronic skeleton I found this on youtube and it's just the coolest thing ever.
This little project is just for myself. It's sort of a challenge to myself. I've never done a skeleton as a finished product before, only as a first step to a fleshed out animal. The whole moveable joints, poseable thing is because I'm too much of a wuss to decide on one pose and have done with it. Or, tom put it in a more positive light, I want the abilty to change my mind about what pose to display it in. Yeah, that sounds better.....
I'm figuring things out as I go along, so if I come across anything that stumps me, I'll be asking you good people for advice. There's more than one way to build a dinosaur, so if anyone else out there sees a better/easier way of doing any of these things I'm trying, chime in, I'd love to hear! I'm hoping this will be as much (if not more) of a learning experience for myself as it is for anyone out there watching the show at home.
To see some more of my stuff, have a look at my Flickr page here:
I hope to post more photos today. Please note that I'm not actually working as quickly as the frequency and density of my posts might suggest. I've been doing bits and pieces here and there (mostly on weekends) for about a month and a half. I'm just catching up to everything I've done so far. After that, things might slow down a bit. We'll see.
Okay, here they are, "fresh out of the oven". Okay, not so fresh; I did the plaster bit a couple of weeks ago. My plaster technique isn't quite as good as it should be; there were a number of bubbles in the molds which needed filling. If you look closely you can see some in the areas of the molds outside the areas to be used for casting parts. Nothing disastrous though. They should suit my purpose.
I'm planning on using the plaster molds to cast papier mache parts, probably paper strip rather than paper pulp. Because I'm using cheap materials, I can always try both with basically no expense except time, choosing the best result for the finished part of my skeleton.
Here's the first stage of the rib cage and another look at the tail verts.
To make the basic rib forms, I enlarged the rib photo in Brochu's monograph to the appropriate size, glued the resulting photocopy to some corrugated cardboard and cut them out.. The actual fossil ribs show much evidence of breakage and some distortion. I used tracing paper to draw the ribs lined up and overlapping each other in order to gauge their degree of curvature and sort them into those which seem to work together to make a (relatively) even body form and those which are too badly broken or deformed to play well with others. On the table beside the cut out rib parts you should be able to make out this drawing (It looks rather like a black and red spider). Right now the ribs are flat, planar pieces. I will be coming back to them to refine their shape and give them a bit of curvature when viewed from the side, as opposed to face on. Ribs don't get a lot of coverage in technical papers and book illustrations. Skulls, hands and feet are all "sexier", or have better publicists.
Back to the back, a tale of the tail.
Here are the tail vertebrae all lined up in a row, together with the haemal arches or chevrons, along the ventral side. Six inch and twelve inch rulers give you some idea of the scale. When I got these all together like this for the first time, my fist thought was "Holy crap, this thing's gonna be BIG!" It has remained my thought since then....
Yes, this stuff is going to be strung together with a variety of things. The "spinal cord" will be some sort of wire. Once the ribs are finished they will be srtong and light. Papier mache (paper strip style) is quite robust once it's dry. Because it's light, it shouldn't be too difficult to affix to the vertebrae, either with glue, or glue with a bit of wire reinforcement inside the joint. I'll use what works. I hope.
The tail won't be covered by much and, if all goes well, it will be more beautiful still. I hope.
I have no formal training in paleontology, but enough reading of the dinosaur scientific literature to walk my way through a lot of the anatomy. I have a degree in history, I've done volunteer work at the local Children's Museum, I do kid's dinosaur programs through the local Public Library (in fact I've got three sessions next week for March Break) , and my day job is at a camera store.
Here are some websites that contain a lot of useful research material for dinosaur sculpting or painting.
First of all, I can recommend joining the Dinosaur Mailing List a great starting place for the latest news and research findings sent right to your inbox. Here's a link to its introductory page. Joining is easy and free. Just follow the simple rules.
Here's a site dedicated to papers pertaining to theropod dinosaurs, like our friend Tyrannosaurus rex and other carnivorous types (some omnivores too), the Theropod Archive. There active links to PDF files of many of the papers listed.
Lawrence Witmer's lab at the University of Ohio does lots of cool, cutting edge anatomical studies, much of which is relavent to dinosaur enthusiasts and artists. CT scans galore give great 3D views of dinosaur innards (and outards too). Have look, watch some movies. You'll be glad you did.
I'm entirely mystified and enthralled by your process, but that will make watching this piece come together all the more enjoyable.
The tail section already looks great. And at 1/10th scale, this should result in a T-Rex that's display worthy, without being terribly overwhelming.
... a cry went up into the shuddering air, and faded to a shrill wailing, passing with the wind, a voice bodiless and thin that died, and was swallowed up, and was never heard again in that age of this world.
Wow, somebody out there was listening: yesterday I was saying how ribs didn't seem to be considered "sexy" enough. Today I find out (through the above-mentioned Dinosaur Mailing List) that there's a paper about tyrannosaur ribs and vertebrae! For those who are interested, the paper is here:
If you've never read a scientific paper before, here's a taste. I haven't read this myself (I just looked at the pretty pictures) so I don't know how much technical language, jargon and anatomical nomenclature there may be, so be warned; you may come away with an expanded (or confused) vocabulary.
Kent Stevens "Dinomorph" pages look at the science of dinosaur movement in three dimensions. Seeing just how these animals were put together and what their possible ranges of motion and postures were helps to ground our view of dinosaurs a bit more in reality.
While we're "morphing", check out Digimorph, the online Digital Morphology library at the University of Texas, Austin. This library has CT scans of hundreds of creatures, including some dinosaur fossils. Some are just the skull or skeleton, some are the whole creature. A useful resource for any figure sculptor and just plain cool.
The Black Hills Institute of Geological Research is a commercial fossil excavation, preparation and reproduction company. Home of the T.rex specimen known as "Stan" and the original excavators and preparators of "Sue", BHI offers for sale both casts of fossils and original specimens.
Hey, Thagomizer! Love your name, first of all. Secondly, this looks like a very challenging and interesting project, and I'll be following along to watch your progress. Thirdly, thanks for the links! That walking T-Rex skeleton in the first post was awesome!
I'm truly inspired my friend.. who'd have thought of that eh? That's some serious undertaking and planning. Wow. I'm very much looking forward to seeing the whole thing through. Many thanks for sharing!
More vertebrae! Dorsals this time. Fairly similar in construction to the tail verts, but the transverse processes are angled upwards and made of thicker cardboard since they will eventually need to support the ribs. You can see the beginnings of the sacrum (fused vertebrae that will be attached to the pelvic girdle), pubis and ischium. The cervical, or neck, vertebrae are going to be a bit more complicated. It will be harder to use the simplified planes that I have used up to now. Still figuring them out.
If you're building something up out of a whole bunch of pieces that look a lot alike (but which are in fact different from each other), be sure to have them clearly labeled with some sort of system to keep them straight. So each of the vertebrae is made up of several parts; each part receives the number (for dorsal) or letter (for tail) of the particular vertebra. This results in a lot of numbers and letters on each vert, helping to ensure that as each one gets worked on ( and I try to work on them in numerical or alphabetical order so I know I haven't missed any) and added to, that at least one of the labels will remain uncovered to enable identification. The same goes for distinguishing left from right for paired, repeated elements like ribs, toes, etc.
A photo of the original fossil mount of Sue confirms that things seem to be going in the right direction. Reality checks like this are important. If you're doing something wrong, you want to find out early. I had just such an experience in the planning stages of this project. I discovered that there were discrepancies in my primary reference between the scale as indicated by the scale bars in the photographic illustrations and as determined from the table of measurements. In some instances the variation was more than 10%. I decided to go by the table of measurements, figuring that there was less chance of figures in a table being incorrectly printed than mistakes being made in the paste-up, layout and compositing of the photos with the scale bar graphic. Fortunately I discovered this before I'd actually started cutting or gluing anything, so all it meant was a bit more work slaving over a hot photocopier. If you have photographic references where a scale bar or some other object of known size is right in the photo, you're laughing. But beware of perspective, as it will change the relative proportions of objects depending on the subject to camera distance. I'll have a bit more to say about perspective when we get to planning out the skull.
One of my next tasks is to start working on hinge mechanisms for the hind limbs. I'll probably use wire for the front limbs, but the rear will need something more robust that will have a more limited range of motion, mostly in the parasagittal (fore and aft) plane.
I was actually able to pull some casts from my plaster limb girdle molds over the weekend. It looks like they came out pretty well, too.
Release agent is Vaseline smeared into the mold with a finger then wiped down with a facial tissue to even out the coat. I use three kinds of paper to make the cast; wrapping tissue (white-onto white plaster- hard to see, harder to photograph) brown craft paper and newsprint, all of which were recovered packing materials from work. FREEE! YIPPEEE! The adhesive used to bind it all together is Weldbond (which, because it is waterproof, should not soften with the later application of any water based primers or paints).
The first layer into the mold, the "gel coat", as it were, consists of the wrapping tissue. Being thin and flexible, it should do best at picking up details from the mold. It's torn (not cut; torn edges blend in more smoothly) into smallish strips (size varies according to the complexity of the shape it is being laid into; flatter areas have larger strips applied to them), dampened and then laid in the mold with some overlap between adjacent strips. Weldbond is brushed in behind; it ends up soaking into the paper. While still wet, a second layer of tissue is applied, with any luck, it will cover spots I missed in the first layer. Press the paper firmly into the mold to ensure good bonding of the layers and good conformation with the interior surface of the mold. (The edge of one of my molds was a bit on the thin side and actually broke, but I was able to mend it and continue with my work.) Paper layers continue out over the mold, beyond the edge of the part boundary.(Make sure that you've applied your mold release to this area as well). This will provide a lip or flange around the part which will make it easier to pry the part out of the mold without damaging the cast.
The next layers are the brown craft paper and the lighter newsprint. These thicker papers will provide most of the bulk of the cast parts, adding strength and body to the tissue layers. Having each layer a different colour lets you gauge your progress and ensures even coverage of the mold. Being a bit on the impatient side, I actually started to layer these papers in while the tissue was still damp, once I was sure that doing so would not mar the tissue beneath. About eight layers altogether are used in this case. Each layer went on while the previous layer was still wet; not all at once, though.
The hardest part is waiting for the lot to dry. If you come back in a little while, they should be ready to pop out.
We've got parts! Yahhoooo! The flange around the part gives you a section you can test for dryness and strength without risking the part itself. If it doesn't seem to be strong enough to come out, add more layers and let them dry.
Once the parts seem ready to pop, find a flange edge and gently pry it up, away from the plaster mold. Try to pry up along the longer side of an oblong shaped part; going along the short side might risk the part folding on you if it's (unbeknownst to you) still not quite ready. In my case, no problems.
The parts look pretty good. I'll get a better idea of the quality of the detail once I get a coat of primer on them, but from what I can see at this stage, they're going to be fine. I'll probably put the scapulocoracods back into the mold and add more layers (including some card) for added strength. They are pretty narrow and more flexible than I would like. I want to be sure they'll retain their shape throughout the construction process. At their current thickness, that might not happen.
Not sure how well it would work for your larger scale sculpt here - but in the past, finding myself in a pinch and also using Vaseline as a sep-agent, I found you can additionally soften or "thin" it to an even softer *brushable* oil-base with a simple blow dryer aimed at the jar somewhere out of your way (blow-dryers can get a bit noisy).
You may not require fine detail on your base casts, but thinning the Vas' a bit allows you to brush it and keeps your hands free, although less moisturized, from petro-based fingerprints. Could be worth a test.
Thanks for the tip, Lilalex! I'm not sure that it would make a lot of difference to what I'm doing and how I'm doing it, but thanks for sharing that with our viewing audience. It sounds like it would help in making castings with very fine detailing
Alas, my household has no blow driers, partly because I don't have a lot to blow dry!
I hope to have more photos up soon. I've got the initial structures for the cervical (neck) vertebrae and the fused verts of the sacrum done. I've also trimmed the scapulocoracoids and ilia that I cast in papier mache. They look quite good if I do say so myself. I still have to apply some paper strips along the cut edges to help seal them and round out the rather too sharp look of those edges. Next up will be arms and legs. For the legs I'm planning on making a hinge joint mechanism using dowels and tongue depressors. I think I'm just going to use wire for the arms and hands; we'll see. If the wooden hinge stuff works well for the legs, I may use the same technique for the front limbs.
What the heck, I'll post some pictures now.
Here's a preview of how I'll start the skull. This is constructed from layers of corrugated cardboard, planned out like a contour map using side and top views mosly. This is an earlier version I did a while ago before I set myself the task of building a whole skeleton. So I'm actually going to do it over again including the internal structure of the skull. Over the cardboard I'll then lay plasticine and sculpt a master that I'll make plaster molds from, in which I shall cast papier mache parts as I did for the limb girdle bits. I'll take more detailed images during the planning and drawing phases so you can get a better idea of how it works.
I've successfully delayed working on the hind limb hinge mechanism! Instead I've done some work on the forelimbs. Initially I thought I would simply wire them up for movement but I've decoded to hinge them as instead. I'm hoping that hinges will limit the out of plane movement at each of the joints so that they don't wiggle around so much. That's the hope anyway. The arms and hands being relatively small, the hinge joints will be made from toothpicks drilled with a pin vise. You can see my start on some of the toothpick drilling in one of the photos below. I've included a diagram so you can get an idea of where I'm heading. Whether I'll get there in the way I want...we'll see.
The upper arm bone (humerus) and the lower arm bones (ulna and radius) will be built up on the cardboard structures shown here. The hands themselves will be completely redone to accommodate the toothpick hinges.
These pictures look amazing, looking forward to the finished "rex".
We have " Sue " from the Chicargo M. here on display at the Auckland Museum & i hope to see her next week and get lots of photos They are also hosting a " Spend the Night With Sue " for anyone who's game !
Am also building a Solar System a present & that's not particulally easy either....
Believe me , I'm looking forward to it being done too! Sometimes I think "What have I got myself into?" But so far it's going quite well. I still have some things I need to figure out. I'm pretty sure I can. We'll all see how this goes as I proceed.
I think you'll enjoy Sue. It really is an impressive specimen. Photos I've seen of the touring casts look very good. Let me know what you think. One thing that's been determined with T.rex since Sue was mounted and cast. It is now known that the coracoids (bones attached to the front end of the shoulder blades)were much closer together than is shown in Sue's skeleton as mounted. Check figure 3 on this link: