Project OAF - Part 2: Initial Casting and Creating Articulation (First Attempt)

Going forward, I’ve decided to dub my efforts to create a series of my own designer action figures as Project OAF (Original Action Figure). I’ve also retroactively renamed my previous article in this series detailing my ongoing Project OAF efforts. I think it’s a catchy name and OAF adequately describes the overall M.U.S.C.L.E. and Eternia Minis-style aesthetic I’m trying to capture with the stylized proportions and overall design of these figures (at least at this early stage, anyway). An extensive project like this just isn’t the same without a working title and Project OAF fits the bill for now. I’m not really concerned with whether or not I’ll give this series of figures a proper title after I complete the final molds for the buck system that will serve as a base template for all of the characters. 

And while we’re on the subject of extensive ongoing projects, I’m splitting the articulation process/Phase 2 into two articles. This one will cover the initial casting as well as the articulation arms and lower body and the next one will cover the head and wrists since this is an incredibly long process and there is a great deal of trial and error to cover here.

This being my first time creating an action figure from scratch, my plan was to create an initial casting of the entire polymer clay sculpture, cut that casting into the parts where I wanted rotational articulation (shoulders, neck, waist, and wrists), and add simple balljoints and sockets. But before any of that, I would need to create a very large mold of the body and a much smaller one of the head, which I sculpted to be removable and would thus would get its own separate mold.

To prepare the mold, I would add air vents to the hands, elbows and feet, with small funnels on the feet to serve as pour spouts and then build up the mold surround using lego bricks. I would then secure the model in place (as well as shore up any potential leaks from the bottom) by pouring in a shallow layer of melted Monster Clay to cover the base of the mold box and allowing it to harden. For the head, I would just create a funnel out of Monster Clay and stick it to the bottom of a tiny beer pong cup.

Due to the size of this mold (possibly the largest I’ve ever made) and coupled with the fact that I was running low on Specialty Resin and Chemical brand Cast-A-Mold 25T tin-cured silicone rubber, I would made adequate use of cut-up chunks of older molds that I’d made with this same silicone rubber. Recycling these unused molds would greatly cut down the amount of fresh material that I would need to mix. This mold was poured in multiple stages, wherein I added the chunks and poured the first layer of silicone. Once that was cured, I added another layer of chunks on top of that and poured the second layer. As you can see in the picture, I needed to top up the mold one more time to get everything fully encased in rubber.

The mold was a success but was so big and heavy that I needed to use these locking pliers to assist with cutting it in order to release the clay model. I still think it’s cool that you can see all the little chunks of recycled silicone fused inside of the mold.

After taping up the mold and casting a copy in what I think was the last of my Model Pro Slow White rigid polyurethane resin (which until now I’ve been incorrectly referring to as simply a urethane resin), I proceeded top saw off the arms and lower body with a coping saw. Apologies for not getting a photo of the finished casting before I started hacking away at it.

I already had an entire red Solo cup full of balljoints that I’d copied from various figures, most of them Masters of the Universe knockoffs and bootlegs, and the next step would be to test fit them against the torso to see which ones would best fit the model. I would lay out the balljoints like so, though the ones pictured here ultimately wouldn’t be the balljoints that I would go with in the end.

It was only after I drilled out some holes for the joint sockets that I decided on what balljoints in my collection would be the most versatile and generally, the best possible size for a 4.5-inch figure.

Going through my pile of reject castings, I came across the legs belonging to a Simba Toys pirate figure from the 80’s and something about them just clicked for me. I think it was mainly the fact that I knew exactly what these balljoints came from and thus, could cast more copies as I needed them. I would not only be using the Simba pirate leg joints for the arms (as shown in the test fitting picture below), but the wrists as well. This would be the same Simba pirate figure whose parts I used as examples in my article about one-part silicone mold making.

But before we can start creating the sockets and crafting the balljoints onto the torso and lower body, I would first need to create the first set of “waste molds” or molds that are used to create castings not of the final parts but the working parts that will be further drilled out, sanded down, glued on, and (as we’ll see later) filled with resin. Since I knew that reject parts and failure would be inevitable and more than one set of working parts would be needed, I thought it prudent to have a set of waste molds of the parts that I’ve already cut from the initial castings and drilled holes in. Otherwise, if I didn’t get it right the very first time (which I knew I had a zero percent chance of doing), I would have to make a whole new casting from the first mold, once again saw off all the parts, and go through the process of drilling out the socket holes. So I went ahead with a set of waste molds for the torso and arms so I wouldn’t have to put myself through all of that again. Think of every set of waste molds that I make as a kind of save point that I can go back as I continue to modify my working parts.

Like I did for the mold of the clay sculpt, I filled the base of these mold surrounds (plastic cups this time) with melted monster clay after securing the bottom of the surrounds to an acrylic sheet with caulking silicone.

I would also once more add a heaping helping of recycled silicone mold chunks to fill out the negative spaces in the mold surrounds and cut down on the amount of fresh silicone that I would need.

With the amount of recycled chunks that were used here, I think it took me less than 500 grams of fresh silicone to fill all three molds.

The first of what would be several castings from this first set of waste molds would be cast in hard epoxy resin (the translucent orange ones) and the FlexIt 90 flexible resin that I use for every articulated figure that I cast. I would also cast a couple of heads that I wouldn’t do anything with until much later. For what I had in mind for creating the articulation sockets, I wanted to try it out on both types of resin.

My initial plan for creating the sockets that would flawlessly interface with my choice of balljoint involved creating a silicone copy of said balljoint, suspending it in the hole I drilled into the arm by skewering it on a Singer sewing needle, and then pouring some FlexIt 90 resin around it. I chose FlexIt 90 because it not only had the fasted cure time out of any other type of resin that I own (90 minutes), it’s ultimately what I will use to cast the final figures (which seem like a million miles away at this stage). After the FlexIt 90 cures around the silicone balljoint, I would then extract it and be left with what I hoped would be a near perfect socket.

I should also note before moving on that I created these silicone balljoints simply by pouring silicone into the leg holes in the lower body from the original pirate figure that the legs came with and then popping them out once they were cured.

Using some Simba Pirate legs (also cast in FlexIt 90), I gave my new arm sockets a stress test and everything seemed like a perfect fit. I could even spin the arm around with the pirate leg attached and the joint remained in the socket. It wouldn’t be until I test fitted these prototype arms to a working model of the torso that I would encounter issues but we’ll circle back to that later on.

Before I get to that whole mess, I need to explain how I made the next iteration of the prototype torso and lower body. Starting with the waist joint, I knew it needed to be deeper than just the waist joint that I planned to use, which would again come from previous castings that I made of that same Simba pirate figure. I poured some blue platinum cured silicone into the waist socket on the underside of the Simba pirate figure’s torso, extracted it once cured, and drilled out more of my figure’s torso so that it would have plenty of room for what would come next.

I didn’t take any pictures of that process but it’s generally the same thing as what I did for the arms. I kept the epoxy resin casting of the torso upside down using a glob of Monster Clay, suspended the silicone socket joint in the center of the hole I drilled out of said torso, and carefully poured some FlexIt 90 around it. While I did superglue a resin copy of the pirate figure’s waist joint onto the lower body of my figure, I knew it would immediately snap off if I tried to do a test fitting. So I just used the lower body from the pirate figure and stuck my figure’s torso onto it. The fit was incredibly snug, the rotation flawless, and everything looked pretty promising overall.

But in order to do a proper test fitting of the newly created waist and arm sockets, I would need to create another waste mold for the torso and lower body after supergluing on the necessary balljoints. Because like I said before, if I tried fitting the balljoints into any of the sockets, the balljoints would snap right off. Hence why I need to create new molds so that the castings will have the balljoints integrated into the respective models. Here they are with funnels and vents added in preparation for their eventual molding. Again, I don’t have any pictures of the molding process, but I used the same blue platinum cured silicone and Lego for the lower body’s mold surround and a plastic cup for the updated torso.

And here’s the castings from the new torso and lower body molds. Even after the 90 minute cure time, flexible resin is still relatively soft so I recommend letting the castings sit overnight (or even a full 24 hours) to let the resin set up to its full 90A shore hardness before sticking any parts together and trying to rotate them around. If you do that, you run the risk of the ball joint twisting off inside the socket and ruining the entire cast. So it's always best to be patient with your resin castings.

Once the resin reached its full shore hardness, I first connected the torso to the lower body and it was fine. There was, however, a bit of a slant that I would need to fix for the next set of molds by adding some epoxy clay to the bottom of the torso, but overall it was still a tight fit with no excessive gaps in the waist and no issues were encountered when twisting the waist. The arms, on the other hand, were a major problem. They fit onto the balljoints and could rotate, but the gaps between the arms and the torso were absolutely horrible. That’s when I knew I would have to go back to the drawing board on my socket creation method.

Worse yet, I knew that I would have to go back to the hot glue method since it was the only method of creating sockets where I can actually see how it fits against the part containing the balljoints while I’m actually creating the socket. I’d avoided the hot glue method in the past because in my previous dalliances with it, it yielded inconsistent results and left behind sockets that looked like a dog’s dinner. But I was running out of options that this point, so I brushed some vegetable oil on one of the arm joints, filled another casting from the arm’s waste mold with hot glue, and held the arm pressed against the torso until the hot glue fully cured.

This was the result of one of the arms, though I would later do a couple of different attempts with the hot glue method to see which ones fit the best before discarding all the other attempts.

These translucent green ones would ultimately be the castings with the hot melt glue sockets that I would ultimately deem fit for the next set of waste molds, wherein I would incorporate not just the socket into the overall part but also the balljoints for the wrists and hands that I superglued onto the stumps after sanding them down. I also made waste molds of the hands at some point (probably when I molded the lower body with the balljoint) but we’ll worry about those later.

Since I was fast approaching the point where “perfect” was becoming the mortal enemy of “good”, I decided that I should leave well enough alone with the arms and make the next set of waste molds out of them. Again, I didn’t see the point in taking more pictures of the mold making process since I do pretty much the same steps every time. So here’s what the castings from the second set of waste molds for the arms looked like in flexible resin). The hands are present because I intend to drill out the holes more to accommodate the wrist joints for when I eventually do the hot glue method for those as well.

I’ll stop here for now and leave you with my working parts thus far. Before Phase 2 can come to a close, I will need to make sockets for and remold both hands as well as make any necessary modifications to the arms so that they fit flush against the wrist “stumps”. I will also have to finalize the design for the head/neck articulation, which I’m thinking will be another balljoint on the torso with a neck sculpted into the head (which I really wish I had done when I was making the original sculpt but it’s nothing I can’t “fix in post”). All of this, I will attempt to cover in part 2.

After that, it’s onto Phase 3 where I’ll smooth out the rough spots, make little tweaks to the working models, and create the final molds for all the Project OAF buck system parts that I hope will act as the base template for this series of action figures.