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Well, I owe some of you an armature tutorial. This is a long-standing obligation from shortly after I created the armature stand tutorial ( video | print ). Unfortunately, a video tutorial will have to wait, but I hope that today's posting will help some people. It's a step-by-step building of an armature, one that can use the stand I showed you how to build in my first tutorial.

This is a warts-and-all blog posting- you're going to see my mistakes along the way, which might actually be more beneficial than if I were to clean it up and make it look like I know what the heck I'm doing. I want to warn you, if you're new to sculpting and are looking for the One Right Way™ to do the armature, that there is no such thing. I have never created an armature exactly like the one I'm building today, and may not ever create another one just like it. Feel free to take ideas from this, but don't get it in your head that this is the best or the only way of doing it. It is one way, nothing more.

In my mind, there are only two rules to building armatures:

1. The armature materials you select must support the weight of the medium sufficiently given the pose


2. The materials you select must be able to safely withstand whatever they will be subjected to. For example, don't select a material with a low melting point or one that releases noxious fumes when heated if you're going to be baking it.

That's it - the only rules. Everything else is just a suggestion.

BTW: Most of the images in this posting can be clicked on to see a larger version

The Concept

I'm doing a comic book character, which is something I've only done once before, and it's a character that I actually never really liked all that much, X-23 from Marvel.

X-23 image ©Marvel, courtesy of Wikipedia

Note:X-23 is a fictional character owned by Marvel. I'm making no claim to the character, and have no intention of selling or otherwise infringing on their rights. I'm simply creating a piece of fan art that will sit on a shelf in my house when completed, something that falls well within the realm of "fair use" in US Copyright Law.

Now, I haven't really read comics in almost twenty years, but when I did, X-Men was one of my favorites, and I always really liked Wolverine. In the twenty years since I stopped following the X-Men, it seems that Wolverine's popularity has grown quite a lot. To capitalize on that popularity, Marvel at some point created a character who was a clone of Wolvie... a clone who also happened to be a hot chick. The idea seemed rather silly to me and I had no use for it.

Well, I recently had an opportunity to read X-23: Innocence Lost which tells the origins of the character. Talk about having my mind changed for me! It's seriously good stuff - they took a corny idea and made it not only seem feasible, they made it work well. This is the kind of comic that makes me consider reading comics regularly again. If you haven't read it, go pick it up in paperback form, it's well worth your time.

So, anyway, I've seen a lot of people do the hot-ass late-teen-or-early-twenties version of X-23. However, the cold-blooded barely-post-pubescent killing machine that we saw in Innocence Lost is the one I want to try and sculpt. So, I photocopied and enlarged a few of the better frames from Innocence Lost, and did a quick armature map of the character. She's just over six heads tall (although that shifts a bit throughout the book), and is fairly realistically proportioned except that her head and facial features are a little bit caricatured and somewhat bigger than a real adolescents would be. She's got the body of an elite gymnast or dancer - thin and muscular. She's going to be a challenge, but a fun one, I think.

I decided to work in twelve inch scale, and figured that she'd be about nine inches tall based on my unscientific calculations. My armature map was drawn at twelve inches, because I did it before I thought about the fact that she wouldn't be as tall as an adult, so I photocopied it and reduced it down to the right size, then traced out lines where the wires of the armature would go in red. Please, no comments on the quality of the drawing, it was a quick sketch and, well, frankly I can't draw for crap, which is one of the reasons I sculpt.

Getting Started

I'm going to build a fairly standard three-wire armature. One wire will be the left arm, left leg, and left side of the torso. Another wire, a mirror image of that one, will be the right arm, right leg, and right side of the torso. A third wire will be for the head. I'm going to incorporate a 1/4" #20 t-nut into the armature so that it can be supported by the support stand. I do this as a general practice; it doesn't hurt anything to have the t-nut in the armature if you don't use the stand, but if halfway through sculpting the piece, you realize you need more support, it's a lot harder if you didn't build the t-nut into the armature at the start.

a 1/4" t-nut

Because this is going to be a thin character, I needed to select an armature wire that was thin enough that it wouldn't show through at the ankles or wrists. I don't mess around with grounding wire, fencing wire, or other types of general-purpose wire, even though there are several kinds that are serviceable as armature wire: I buy actual armature wire. It's relatively inexpensive if you buy it on larger spools. For this particular sculpture, I chose a 16 gauge aluminum alloy wire.

The armature wire I'm using

Most of the time, I will double up the wire on the lower part of the armature and twist it together with a drill (you can see an example of making legs out of twisted wire in the larger armature I built a few months back here, although that one has telescoping arms done with several wires). This means that the twisted wire through the legs would be twice as thick as the single wire in the arms. This makes sense - the bones of the lower body are weight-bearing and proportionally larger than the bones of the arms, so doubling the wire from the waist down is often a good idea since it allows a single gauge wire to be used for the whole piece while still giving you the ability to have larger and stronger wire where it needs to bear more weight.

For this particular piece, I was worried about those damn thin adolescent ankles, so I'm leaving the wire as a single-strand and not twisting it for the legs. I'm going to embed that t-nut into the armature, so if the 16 gauge wire isn't strong enough to support the clay on its own, I can stick it on the armature stand to give it more support.

Measuring Up

Now, I unspool some wire and line it up with the armature map. This will allow me to measure out the approximate amount I need for the left-side wire. I always leave a fair amount extra below the feet; I can snip it off later if I don't need it. I then do the same thing for the right-side wire, but I don't worry about the head wire for now.

using the armature map to measure the wire

Next on my agenda is to join the left and right side wires, but when I do that, I want to embed that 1/4" t-nut into the torso at the same time. In order to incorporate the t-nut, I find it useful to flatten those sharp points down. A pair of needle-nose pliers does the job easily and quickly. With sixteen gauge wire, you could simply choose to leave them as they are—the wire will fit between the sharp parts—but I prefer to flatten them and reduce my chances of injuring myself. The process I use is to grip the piece to be flattened in the very tip of the needle nose pliers and use leverage to bend them down as far as I can.

flattening the sharp points on the t-nut

Then, place the mostly-flattened piece into the flat part of the pliers, and clamp down.

finishing the job

Joining the Body Wires

Now it's time to put the t-nut and the two body-wires together. I first use the armature map to determine where to locate the t-nut between the wires, choosing a spot where I know the t-nut will fit, and where it will provide good support. I chose a spot a little above the navel. To join the wires and t-nut, I generally use a fast-setting plumbing epoxy like FastSteel. You don't need to use this particular brand, but I've had good luck with it. It cures in five minutes rock hard. To use it, you simply slice some off, mix it thoroughly, then squish it into place with your fingers. Then go wash your hands; it's kinda nasty stuff.

FastSteel putty is great for building armatures

I line up the two body wires around the t-nut, and use some mixed FastSteel to secure the wires around the t-nut.

the wires and t-nut connected by the putty

I always find that during this process, I get the wires pretty bent out of shape. Fortunately, armature wire can be bent many times without risk of breaking, so I simply line everything back up with my armature map before proceeding.

lining everything back up

Next, I take a sharpie, and I mark some key points - the elbows, the knees, and the bottom of the feet. Sharpies are supposed to be permanent, but on aluminum wire, I don't find that to be the case, so mark well, and then try to avoid rubbing those spots. After marking, you can brush a little super glue over the marking to make them more resistant to getting rubbed off.

marking some points of articulation

Attaching the Head Wire

I used to try and get the head wire into the epoxy putty when I was joining the two body wires. More often than not, I would screw it up trying to keep all three wires and the t-nut positioned while the putty cured (having only two hands is sometimes so inconvenient), so I no longer even attempt to get them all joined the same time - I ignore the head wire until the putty that joins the two body wires and the t-nut has completely cured. Then I drill a very small hole in the cured putty - I use the small drill bit that came with my Dremel to do it.

drilling a hold for the head wire

Next, I cut another piece of sixteen gauge armature wire, making sure it's long enough to reach from the t-nut to the top of the head on the armature map. When in doubt, go long, because it's easy to cut long wire, but it's awfully hard to stretch short wire out. I insert this cut piece into the hole I just drilled. It's a little wobbly - no worries, we'll secure it in a minute.

Wrapping the Torso

Before we secure the wire, we have to insert something else in this hole - another, smaller piece of wire. The three pieces of aluminum alloy wire that have already been cut is all the armature wire that we're going to use. We will, however, be using some floral wire - the kind you can get at any craft store - to wrap the armature wire. We do this to accomplish two things. First, it helps secure the existing wires. Second, it gives the clay more surface area to hold onto.

good old floral wire

For this part, I'm using 28-gauge floral wire. Why? Because that's the one I grabbed. There aren't any rules about this, just pick the wire that seems right, or the best one you've got in your inventory. It's trial and error, and you'll develop a feel for what gauge to use. I actually decided after this step that 28 gauge was too thin and switched to 24 gauge. But the 28 is functioning fine, so I'm not going to bother re-doing this step.

the floral wire inserted into the hole along with the head wire

Once the floral wire is inserted into the hole, I'm going to wrap. First, I start by wrapping all three pieces of armature wire together, but when I reach a point about halfway up to the where the arm wire bend, I'm going to switch to wrapping only the two wires of the torso, and not include the wire of the head in the wrap any more. The reason for this is simple - it's a more accurate representation of human anatomy. The vertebrae do not come up from the body perfectly straight, they jut forward at an angle. Additionally, the scapula and shoulders have a relatively large range of motion and can be considerably further back than the spine in many poses. By wrapping the wires this way, I can have the head at the proper angle and also will be able to put the shoulders into more realistic positions.

wrapping first all three wires, then just the two torso wires

Now, to secure this wire in place, I'm going to use super glue. Okay, technically, it's Krazy Glue™, but I've always called any liquid capable of securely and inconveniently attaching my forefinger to my thumb or another body part "super glue" and I'm not likely to change now.

this doesn't really need a caption, does it?

For this job, I like the brush-on kind of super glue. I'm just going to lather the stuff over the wire wrapping job I just did, and make sure some gets down into the hole I drilled. Once this dries, those three wires should be nice and secure. If they're not, you can mix up a little more putty and shove that into the hole, but for me, the super glue has worked just fine and secured everything nicely.

Forming the Core of the Head

Next, I take some needle-nose pliers, the round kind sometimes called "ring bending" pliers of just "ring benders", and bend the head wire down to form a little ball to form the base upon which the head will be built.

Wrapping the Legs

Now, I'm going to wire wrap the two legs. This is a very similar process to wire-wrapping the torso above. I'm going to drill a tiny hold in the putty between the spots where the leg wires emerge, insert the end of a length of 24 gauge floral wire into it, then wrap it down one leg wire, then I will repeat the process with the other leg. I'll stop wrapping when I reach the mark I made for the bottom of the foot because the wrapped wire will interfere with inserting the wires into the wooden base later.

drilling another hole

floral wire wrapped down one leg

Once both legs are wrapped, I whip out the brushable super glue again, and lather down the wire wrapping job, making sure I get plenty in that hole I drilled, then I let it dry for a minute or two.

brush the wire wrapping with super glue again

Wrapping the Arms

Now, I just need to wire wrap the arms, so I take another piece of floral wire, and stick it down between the wires that are already wrapped around the torso.

sticking the floral wire down into the torso wires

Once I've done that, I bend the wire and start wrapping the arm, just like I did with the legs.

wrapping the arm

Once you've got both arms wrapped, it'll look something like this:

And, of course, just like with the legs, lather it down with some super glue and let it dry. I then trim the floral wire down to the length of the arm.

Attaching it to the Working Base

We are getting there. Almost done. Really. Next thing I do is to cut a small piece of wood to act as our base. I could have chosen to attach the armature right to the sculpting stand we created earlier, but I like to give the armature its own base. I figure out where I want the feet to be positioned, then drill two small holes in those spots. I'm going for a classic Wolverine pose with feet just a little more than shoulder width apart, so I drill two small holes at the appropriate locations. I want the wire to just barely it through the holes, so err on the side of drilling too small of a hole, then gradually widening until the wire can be inserted, but is still snug.

I now run the wires through the holes. I push the wire right down to the line I marked for the feet. I could also leave a little space below that line for a base. I'm going to push right to the line - if I sculpt a base, I will do it later after at least one bake.

You can attach the wires to the base using more epoxy putty, or with screws if you want. What I'm going to do is cut a groove with my dremel for the wire, then wrap it back up around the wood so that it holds it secure, but can be undone later.

And, She's Done

And here's what my final armature looks like.

You can see the wires I wrapped up from below on the base behind the armature. I anticipate taking the armature off this piece of wood later and sculpting an actual base for it, so I want the extra wire, and don't want to attach it permanently if I can get away with it. With larger or bulkier pieces, you may find you have no choice but to affix the wires to the base more permanently and leave room for the sculpted base right from the start.

Here's a picture to show it on the support. I was worried about the thin gauge wire, but honestly, I think this is going to work fine even without the back support, but it's nice to know I can add the back support if I need to later.

This armature is missing one thing, however. Did anyone spot it? It's specific to this character, not something you'd do with most armatures. Yep, the blades coming out of her arms. Frankly, I haven't figured out how I'm going to do them yet. I'll do a post when I figure out how I'm going to make those darn blades.