Figure Leaning

I posted this report over on Danny Choo- a common problem with anime figures is that they tend to lean after a while- although the solutions may be obvious if one thinks about them, I wanted to elaborate. Enjoy! technical jargon approaching.

Introduction

Figures are an icon of the Otaku culture and are beloved by fans everywhere for their amazing sculpts and attention to detail. Unfortunately some of our figures lean and bend after a couple of months to a few years. With my experience in manufacturing engineering I will attempt to explain what is going on with our figures. I cannot offer solutions to the problems, but I can present the problems to where think tanks can address them.MaterialsFigures are generally made out of Polyvinylchloride, more commonly known as PVC. This material is known for its rigidity in the construction industry across the world as a building material for pipes, ducts, etc. It is also used in toys and figures alike (minus the dangerous chemical DEHP). From the community I also heard ABS is used in figures. ABS is a very strong and rigid material, but is much more expensive than using PVC.

ABS, to my knowledge also has difficulties in applying plasticizers and additives, thus making figures more expensive to make (which you don’t want!).All about Polyvinylchloride (PVC)PVC is used in the construction industry for piping and has a great surface area in a tubular form (cylindrical, pipe, whatever you want to call it). PVC is very easy to work with and mold into shapes that are needed. Plasticizers and additives make the production process even easier: however there are serious drawbacks to using the two (IE- leaning).

PVC has a linear molecular structure which is common in thermoplastic polymers. Since this molecular chain is linear and basic, this form of thermoplastic polymer (PVC) tends to retain characteristics of an elastomer, or stretchy/rubber material. In short, PVC is flexible and stretchable. If you have ever tried to bend an arm on a figure to an extreme degree and let go, the wonder why the arm returns to its original position (I AM NOT INVITING YOU TO DO SO!) then this is why. Making FiguresIntuitively, the best way to make figures is to create a mold from the sculpted prototype, then go from there into production. Extrudate probably still comes out of an injection mold machine, then the material is poured into a mold (more than likely re-useable, and I am sure the plants have many of the same mold around). The mold is left to dry and harden, and then the figures are removed from the mold, inspected for quality and then painted by craftsmen/craftswomen with an airbrush.

Figures have more details than action figures- so the mold making process will be more complex and will cost the factory more money to produce a limited amount of figures. Don’t get me wrong- factories probably produce many figures, however compared to plastic bottles, screws, etc they are not making as near enough product as say a bottling factory. To mass produce is to save money, however with complex products that have a limited production run, sometimes it is more advantageous (and cost effective) for the factory to have limited runs and re-use those molds to attain the best level of detail possible.You are going to get what you pay for- figure making is a complex process where artists must sculpt a prototype, make changes, then a mold must be produced, more molds produced then the factory must make adjustments to machinery to begin a run of a certain figure. If you wondered why figures cost so much, it is much more than just import prices- it is the way figures are made and there is nothing that can be done to really lower the price in terms of selecting a better method.

Figure Design

Leaning is half a design problem rather than a chemical one. When PVC is molded into a shape using molds, the body is a solid structure rather than a hollow one. Doing this will increase the weight on the figure substantially if not properly distributed. If more weight is offset from the center of gravity and the legs are not strong enough to support the upper weight- bending, or deformation of the material occurs. Due to its elastic properties, PVC will retain its original shape, but will not stay in its previous place.

In short, the material is too flexible due to the plasticizer and additives added to the PVC during the injection molding process that produces extradite. Thus, it can be said that bending may be due to a improper placement of the center of gravity rather than the material being too heavy- though that may have something to do with it.Supports will be necessary to aid in the distribution of the offset weight. If the center of gravity is placed perfectly, and the legs are not designed to hold up this weight, then a perfect deformation should occur where the figure will “bend over” in the “bend over” pose (think Queens Gate Alice). If the center of gravity is off, like

I have seen in many figure photos, then the figure will lean in the direction of the displacement between the center of gravity and where it should have been. You would think pegs inserted into the legs would fix the problem- however this may exacerbate the situation by making the legs fixed and rigid. If the figure is not fixed, and the center of gravity is off, then the figure will simply fall over.

Conclusions

I said PVC was rigid in a tubular structure, but as a solid body (rigid PVC tubing is NOT a solid body) PVC is a thermoplastic that contains some elements of an elastomer. The job of an elastomer is to deform- rubber bands deform to absurd numbers and rubber tires are designed to change with air pressure to a certain PSI rating.

Plasticizing and adding additives to the manufacturing process is necessary in making the material more workable and to keep costs down. These and heat only add to the problem by giving the PVC an even more elastic structure. Figures are also flexible for another reason- it minimizes the chance of a defect as the PVC sets in the mold, thus why the additives and other stuff is added into the process.With that said and covered in the basics, does anyone have any ideas to secure their figures?

Each will require a unique solution; but perhaps an ugly solution (support bars made of brass or steel, that stuff is uber) can turn a sticky situation (NO pun intended) into a somewhat manageable one. After writing this article, I came back to read ornehx’s post on what Danny said was the main problem with leaning- well I guess I said the same stuff but used a bit more detail =).