Jointing Ball-joints!

I've made an arm so far and I used wooden beads for the joints. Now this was just a first try, and belive me it's not going to be my best work. The beads worked pretty well. You CAN bake them because the teperature that polymer clay cures at is no where near the burn-point for wood. My only problem that I had was when it came to sanding. To keep down dust I decided to wet-sand the clay, and like a moron I forgot that 'Hey! Wood expands when it gets wet! Duh!' It didn't cause too big of a problem. I just have a couple of cracks to fill in on the upper arm, and the joint on the lower arm has now popped off but it's nothing un-fixable. I've seen people make clay balls for the joints in a couple of tutorials but I haven't tried that method yet.

 

I made my ball joints out of polymer clay (Prosculpt), and cut the slits out with my exacto knife.

 

Sometimes a perfectly round shape isn't...well...perfect. Some dolls have more disc-shaped joints (imagine a ball squished between two parallel planks) because it creates a better silhouette when you view it from the side. Some dolls have egg-shaped joints for better load-bearing/standing/smooth transition. And with beads and wooden balls, sometimes you just don't get the exact size you want :\

All said, I plan to sculpt my own joints. Out of super sculpey. And then sand down bumps and fill up dents. Here's to my first try! XD (By the time I'm done, I expect I'll need a good, strong drink)

Polymer clay is pretty soft. Especially if you're boiling rather than baking during your working process. It can be cut with an xacto knife, scraped with clay and dental tools, or sanded down with a file/sandpaper. Though the woooo-wooooo-wooooo of power tools certainly speaks loudly for itself XD

 

Here's what I just spent the past few days doing:

1) Find marbles/ball bearings of appropriate sizes.
2) Use Apoxie Fixit Sculpt to attach 1/4 inch bits of straws to opposite sizes of each marble, filling in the entire piece of straw.
3) Make a two-part silicone mold of each marble.
4) Insert a piece of straw cut to the appropriate size into the molds.
5) Cast resin.

Voila, resin "beads" of the appropriate size, with holes big enough for stringing. I'll carve the slots with an X-Acto.

Unfortunately, I didn't have enough silicone to make really thick mold walls, so some of the spheres bulged a bit... and it was raining when I cast, so they're full of tiny bubbles. I think I'll be able to work with them, though.

 

Logodae:
So you make the resin joints first, then...connect them to your sculpey sculpts...THEN mold/cast the whole thing?

 

Yup. Or that's the plan, at least...

I'll probably use Apoxie Fixit Sculpt to join the sculpted Sculpey pieces to the cast resin bits. And I know casting the joint spheres seems kinda like overkill, but I couldn't figure out another way of getting spheres in the sizes I needed with holes in them... power tools scare me.

In retrospect, I probably could have done it with flexible Sculpey press molds, as long as I filled the straws with something hard. Ah well, at least the silicone is recyclable. And I learned many useful things in the process, like "don't try to make a pour hole double as an air vent," "don't skimp on the silicone," and "don't cast when it's raining."

 

I am envious of you. Money is tight and I can't really afford silicone at this point...

For joints, I'm just going to make balls a little bigger than I need, boil them in water, then slowly sand them down to size. It helps that I have those plastic templates with different circles in millimeter diameters on them.

For holes, I'm using a clay tool to carve a crater, and then maybe use a hand file or something to gouge it through?

Getting the perfect size and fit seems like a harder task than making the hole, actually. The way I look at it, the prototype doesn't have to have stringing holes, because they can be created in the molding/casting process as described by lollipop...

But then, what do I know? It is my first doll >_<

(Logodae, I'm impressed with your Jasper! XD Foxy man foxy man! XDDDD)

 

I cast balls based on ready-mades like Logodae, except that I use plaster and cast the balls in Das clay rather than resin, so that it will be the same density as the rest of my doll as I make it and because I don't put the hole in until later in the process because dead-center isn't always the best place for it, I find. What is the difficult part is finding beads the exact size I want. I live in the US and so all the wooden beads the craft stores carry are in Edwardian measurements, whereas I tend to use metric for my dolls, and also you're kind of stuck with standard sizes that way, all the sizes go in increments of a quarter-inch and that's too much difference between the sizes for some of my joints, like I ended up using the same size bead for my shoulder and knee joints, though the knee, since it has to sit all inside the leg, should be smaller and I had to sand it down a lot.
I don't use the beads themselves for the joints, I use them as blanks to base plaster molds off of, I make the mold so that I'll have a finger sized hole at the top of the molds so that I can push Das clay into them from the top, then I take them out and set them out to dry. Das clay dries really slowly, so for a 60cm doll, here I work on something else for two or three days... I attach the balls before drilling holes in them, since on the hip and elbow joints I tend to have them a bit off center, then after I've finished most of the leg, I take them to the drill-press (it lets me be a bit more accurate than a hand-held drill) and drill through the balls into the open tube space I left in the limbs. At this point, to make the slits, you can use a hand tool, it just takes a long time, I use a dremel tool to cut the down the side of the ball for the rest of the joint movement.