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How I rearticulated my badger skeleton, part one

Jake

Right, this was going to be just one post, but it's so big I've split it into two. I did three big posts last year here, here and here about how I rearticulated my fox skeleton Vulpy, so I'm not going to do a step by step guide, but I will write about how I did each step. The big rush for this badger skeleton (called Emily) was that I had to take it up to the filming of BBC Winterwatch, and although I had about three week's notice, it was still a big rush. Rearticulating skeletons properly takes LOADS of time.

The picture at the top is a bit of a cheat. That's how I would really like it to look (it's been retouched). In reality it is VERY difficult to rearticulate a skeleton without any external wires or poles and while I'd love to do it that way, there are LOADS of problems.But I think the post is really good, even if I ended up at it by accident. Anyway, this is how I did it....



Getting started



This is everything that we needed to make the badger skeleton. It's pretty similar to everything I used for Vulpy: four different thicknesses of wire, a hand drill, string, dental floss, a pencil and normal glue. There are a few extra things, I'll come to those later on. The banana was just a snack.

Last year everyone laughed at me using a hand drill but it works pretty well. It gets clamped to the table, and you turn the handle with one hand and hold the bone with the other.



How to support the skeleton


This is the BIG question you need to decide before starting. What pose is it going to be in, and how will it be held up ?

Vulpy was running and suspended by threads, and she hangs from a grid with is screwed into my bedroom ceiling. When I was asked to bring her up to the Winterwatch studio, I had to think how to do this. Dad suggested a simple base and frame which the grid could be attached to. He came up with this which is simple, but strong enough to hold Vulpy, then afterwards the grid can be taken out and refastened onto my ceiling. 

Because the badger was going to go up to Winterwatch as well, it made dense to do the same idea. This frame was slightly shorter, and exactly the same height a so that the badger could go either in the frame, or from the ceiling, so it looks like it is standing on one of my shelves.

This is the frame that dad made for the badger for WinterWatch:

  
The weight of the badger is held by dental floss around the skull and at three points along the spine.


I drilled a hole in the base to support the paws. The wire goes from the lower leg bones, and is mostly hidden. This stops too much stress being put on the shoulders or hips.


When dad originally made the badger frame, he did it late at night, and he accidentally built it all the way around his workbench, and had to unscrew it and rebuild it !


The frame was useful when building the skeleton too. Having it supported but still loose helped work out what pose I could use.

The spine

This was one of the very first steps. I used a long length of string with through the vertebrae, and sorted out the vertebrae into the four main groups (neck or cervical, rib cage or thoracic, lower back or lumbar, and tail or caudal.). Cervical and lumbar vertebrae tend to slot together in a particular order so you just have to keep trying. Thoracic vertebrae are more similar.

The neck vertebrae have two extra small holes in them:


Here's the lower back. See how the one on the right has that hollow, but the one on the left doesn't ? That's where the end of the rib fits. Badgers have 15 pairs of ribs, so this means that this would be the last pair fit. 



This is all 15 thoracic vertebrae, with the head-end on the right:


The one big difference I did with this skeleton which I didn't do with Vulpy was to add spacing between the vertebrae, to show how they fit together in real life with cartilage discs: 


I used these pads from B&Q, and trimmed them to size. One mistake I made was to not leave gaps at the aide so the ends of ribs could fit in properly.


When I rearticulated Vulpy, I used a length of wire covered in foam, which I bought from Maplins, and which was called something like a 'bendy wrap". But I couldn't find anywhere that sold them any more, so I decided to drill through the solid bit of vertebrae, like this. I used two holes, so the vertebrae wouldn't rotate round on the wire:


Here's the lumbar vertebrae held together like that.


And here's the lower part of the spine done like that:



This wasn't as good an idea as it sounded at the time. The vertebrae were quite brittle, possibly because I simmered them too long or used too much biological washing powder. As I pushed some of them down the wire, one or two started to split. At about half way, I had to use just one hole, because the  vertebrae wasn't big enough for two holes. The other problem was, if you drill two holes one way, it makes it more difficult to drill another hole at right angles to attach the ribs:



Here are the holes drilled where the end of the ribs would be:


And this is how the wire was pushed through then trimmed:


The neck was going to be difficult doing it this way, so I used plastic tubing through the main spinal cord hole, and pushed down lots of wire strips inside at the head end, to help hold it up.


This is the entire spine hanging up when it was done:


The ribs

The ribs were the hardest part to get right. I had paired them then matched them to each vertebrae at the start, then had drilled holes to attach them right at the start.


This was the very first pair of ribs. Each rib has two attachment parts at the vertebrae, the very end (which goes close to the vertebrae) and the bit which is a bit further along, which attaches to the 'wing' on each side. The more well defined the second attachment is, the closer to the head it goes. The back ribs get smoother and smoother. On the front ribs, I drilled two wires in, one for each attachment. On the back ribs, there was only room for one. I also drilled a hole through the bottom of the rib, to allow a wire to go through for extra strength:



I trimmed the wire to just fit in right. Where I could, I threaded the wire through to the other side, so the pairs of ribs were attached together through the vertebrae.


This pair were from the middle-to-back end of the ribcage, which you can tell because the second attachment isn't as well defined as the first pair above:


When attached, I used a dab of glue, then held them on overnight, sometimes using string. This doesn't look the best, I know:


At the other end, the threaded wire helped space the ribcage:


I'm still not happy with the ribs, this was the weakest part. If I had had another week I would have done them again, but it was rushed through for Winterwatch.

Attaching the pelvis


The big difference between this badger and when I prepared Vulpy is that the sacrum - where the pelvis attaches - is not properly glued on here, but the wires slot into it. The sacrum and femurs are attached to the pelvis by drilling through holes, inserting wires, pushing the wires all the way in, and putting a tiny amount of plaster in the holes at the end. The two halves of the pelvis are connected by wires in the same way I did Vulpy, and then I drilled through to the sacrum in the same way. Then I added glue ont the joins, and pulled together with two elastic bands overnight:


The black dot neat the sacrum is one of the drill holes. When it was filled with plaster it was invisible:




Attaching the leg to the pelvis was done in a similar way, with two drilled holes in the socket and head, and wire attached, then the socket was filled with glue and left overnight:


The angle of the femur was REALLY important at this stage:



In my next post, I'll write about how I articulated the rest ! (UPDATE: Here it is !)

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4 comments :

DaisyDebs said...

Brilliant Jake! I have just ordered my copy of your book by the way ! : ) I cant wait to share this with my little grandson .

Psydrache said...

Who laughed about your hand drill? These people don't know how useful these kind of drills are.
Your new skeleton is so awesome! And it's a good idea using the felt pads. I hope I could rearticulate a skeleton one time, too.

Jake said...

Thanks ! I have a gallery on my Facebook fan page of people with my book: send a picture if you can !

Jake said...

I can't remember, but I think it was Ben Garrod. But then he rearticulates horses among other things, so a handdrill wouldn't probably be powerful enough.




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