Smart Doll Cortex

POSTED BY DANNY CHOO On Mon 2019/04/15 22:21 JST
In the not too distant future, Smart Dolls will be able to make themselves the way humans do.

How to build

The instructions to build Smart Doll Cortex live here but don't proceed until you have read this entire article - you need to know what you are going to spend your hard earned moolah on before you proceed.


Hey there! I’m Danny Choo the creator of Smart Doll and today I would like to give you the lowdown on Cortex.

Shortly after releasing Smart Doll in June 2014, I said to myself that vinyl production was going to be a major bottleneck in the future which would jeopardize the future of our business. The lengthy times needed to make vinyl was not only costly but labor intensive too.

At the time of startup, we could only afford vinyl molds which cost much less than injection molds. Vinyl molds can cost thousands of USD (where production is slow and unit costs are expensive) while injection molding molds can cost hundreds (and hundreds) of thousands of USD (where production is fast and unit costs are inexpensive).

I started to look into creating an injection molded version of Smart Doll but all my industry peers and their dog told me that it wasn’t possible to make a doll of this size (60CM tall) as a plastic kit while retaining the matte look and feel of vinyl. I scoped out many model kits already on the market but didn’t find any that matched the quality that I was looking for. I said to myself “well if the big players couldn’t do it then how could I?” and then I just gave up and said “woof woof.”

In 2015, the business grew to a point where if I didn’t do something about the approaching bottleneck, our business would remain at the same scale doing the same thing forever and I would have died not knowing whether I could have done something to change the trajectory of the business and perhaps at the same time create a new genre of product.

I decided to take the risk of using up pretty much all of our cash flow and proceed with the research and development of an injection molded version of Smart Doll - the project was to be called Cortex. “Cortex” in latin means “outer shell” and in anatomy it refers to the outermost layer of an organ - the Cerebral Cortex for example.

We refer to Cortex as the injection molded parts which is made out of a plastic called Asaflex.

Vinyl slush casting - great for small production but completely unscalable.

Our vinyl and Cortex parts are made in Japan along with the molds. Vinyl parts are created using a method called “slush casting” - liquid vinyl is poured into a single mold and heated in an oil bath for a few minutes. The longer its kept in the bath, the thicker the walls of the part will be. The end result is a seamless part that has a funnel attached (flash) which must be cut off. This is a simplified explanation but much more is involved including spinning the part on a centrifugal spindle and placing the mold in an air chamber to remove air bubbles.

Cortex parts are created using injection molding where the pellets of Asaflex are heated in a barrel that are then injected into a two piece mold at extreme high pressures - this naturally tries to force the mold open. A clamping force of 450 tons keeps the molds pressed together during the injection process.

However, no matter how high the clamping force used, parting lines always appear on injection molded parts.

Just a small fraction of the Cortex prototyping and development.

Cortex is the most challenging thing I’ve ever worked on. Nobody had created anything similar in this size so we had to work out how to do it ourselves. 3D prints helped vastly in visualizing concepts but they don’t have the same properties as the final material.

After creating the molds, we see for the first time how the material and shapes behave under certain circumstances - it was this phase that took the longest development time. The molds were actually ready at the end of 2017 and took over a year of modifications to bring the product to a consumer level.

It was so disheartening when things didn’t work out after each modification which sometimes took months on end. But without the downers, we wouldn’t have gained the knowledge needed to improve the product.

Smart Doll supported by owners in over 88 countries. About half of our monthly sales are new acquisitions.

Come 2019 and we see that the volume of Smart Doll has increased exponentially - we have not been able to keep up with demand due to our capacity to cast vinyl which amounts to a mere 1000 dolls per month.

But timing has never been better - the 4 year project to create an injection molded version of Smart Doll called Cortex is now ready. With Cortex we can now mold hundreds of thousands of dolls per month and we have now created an alternate timeline thus enabling us to save the clock tower.

Smart Doll Cortex - completely compatible with our existing apparel and accessories.

As previously mentioned, the aim of the Cortex project was to invent a way for us to increase production volume through changing the molding method but it was essential to keep the exact same shape and form of Smart Doll.

We designed Cortex to be completely compatible with the same internal frame that we use for the vinyl version of Smart Doll - this means that all vinyl parts such as hands and busts together with all apparel, accessories and wigs are compatible with Cortex. The fundamental differences between Vinyl and Cortex is the type of material (and its properties) and with the way it’s put together.

While we were developing Cortex, I was sharing progress on social media and discovered that many folks wanted to put together their own Smart Doll. This was a great! If folks could build their own Smart Doll then we wouldn’t need to do it ourselves meaning that we could pass those savings onto the consumer.

Smart Doll Cortex - molding times are vastly improved but assembly time is about the same as vinyl.

However, Cortex was never designed to be put together from scratch by a consumer like Gundam or Airfix models - it was designed for our staff to put together. Just like the vinyl version, there is a lot of post processing to be done to the shell parts including sanding the surfaces and deburring. As for the frame - it requires special tools, greasing, deburring, torque adjustment and testing.

The frame (known as Mirai Frame) is actually used to decide who we hire. During the Mirai Frame Challenge, folks who can make Mirai Frame in an hour are hired straight away. Everybody who works on our production team has taken the challenge.

Consumers of model kits do not expect to put together a model that requires such labor or skill. However if we designed Smart Doll to be built by consumers from scratch then we would need to meet their expectations and sacrifice the durability of the structure. Fully clothed, Smart Doll can weigh 1 kilo. The internal frame and outer structure needs to be sturdy and withstand its own weight.

This is one of the reasons why some plastic model kits feel light and tend to fall apart in your hands - they are designed to be built by consumers. There seems to be the understanding however that the modeler will use their own ninja skills to improve the model by implementing their own modifications.

I do ultimately want to release Cortex available as a kit but some things need to happen before we do that.

Cortex will be launched in stages using the MAYA (Most Advanced Yet Acceptable) Principle proposed by industrial designer Raymond Loewy. The principle states that consumers seek novelty (neophilia) but when presented with concepts too advanced, most consumers become opposed to the idea (neophobia). The solution is to design for the future but deliver the future in steps.

The packaging for the Cortex Kits.

The first step is to release Cortex as a fully assembled Smart Doll - this was the original plan. Once the market is familiar with the product then we will start to introduce the Cortex Kits. I mentioned earlier that the frame needs special tools to build so we are creating new parts which do not require such specialized tools. These new parts won’t be ready until the end of the year though. The first Cortex kit we will release is called “Cortex Ninja Grade” (CNG) where the frame is pre-assembled. Then later in the year we will release “Cortex Final Boss Grade” (CFBG) where the entire Smart Doll (including frame) is assembled by the consumer - this will be the most inexpensive version of Smart Doll.

Folks who can do Final Boss Grade perfectly (perfect as in not being hit once on Street Fighter) will be subject to recruitment calls from me as I would like you to come work for us.

Cortex parts are designed with a snap fit but for extra durability we glue the shell parts together.

Smart Doll Land Glossary

Before we continue let’s get familiar with some of the lingo we use at Smart Doll Land.

Shell - The outer “skin” of Smart Doll.

Cortex - Injection molded shell parts.

Vinyl - slush molded shell parts.

Frame - the internal skeletal structure of Smart Doll.

Vinyl Smart Doll - vinyl from head to toe - this is what we have been making since 2014. These are assembled by us.

Cortex Complete - a Smart Doll where the entire body and head is Cortex. These are assembled by us.

Cortex Hybrid is a term meaning that the head is vinyl and the body is Cortex. These are assembled by us.

In some cases for Cortex Hybrid we would ship with vinyl hands and bust but if this is the case the product description will mention so.

Cortex Ninja Grade (CNG) - A Cortex DIY kit where the frame is fully assembled but you assemble the shell.

Cortex Final Boss Grade (CFBG) - A Cortex DIY kit where you assemble the frame and shell yourself.

Listed below from the most expensive on top to the least expensive at the bottom are the various Smart Doll products.

[most expensive up here]

Licensed Cortex Hybrid Smart Doll

Vinyl Smart Doll

Cortex Hybrid Smart Doll

Cortex Complete Smart Doll

Cortex Ninja Grade Smart Doll

Cortex Final Boss Grade Smart Doll

[least expensive down here]

Our own Smart Doll characters will always be less expensive than licensed products.

About licensed Smart Dolls

All licensed Smart Doll girls will be Cortex Hybrids. Because we are now able to make substantially more, we can allocate more of the cost to the apparel and accessories of the licensed character.

We are now on a timeline where we can produce more Smart Dolls meaning more licensed products. However, while flash cutting time is reduced for each body part, a human still needs to post process, assemble and glue the body together so labor costs don’t actually change that much.

License deals vary between anime, game and Hollywood studio. Some charge a percentage of the retail price which can range from 3% to 33%. And then some charge what’s known as a “Minimum Guarantee” also known as “MG” - this basically says “put this much down on the table before we start talking” lol.

MG can range from 10,000 USD to 100,000 USD depending on who you are dealing with.

These costs are factored into the licensed product which is why they end up costing substantially more than our original Smart Doll characters.

We perform torque tests on the limbs to ensure that joints are sturdy and not flop about all over the place

Setting Expectations

Ever since we launched Smart Doll back in June 2014, we have always made a point of setting expectations about what the product is and is not. It is in our interest that a potential customer is provided with enough information to make a purchase decision even if that means they go for other brands. As an analogy, we cannot build a strong brand if we sell peanuts to a customer that we know has a peanut allergy - we may pocket some extra change in the short term but we would be shooting ourselves in the foot for the long term - but we need our feet because we are in this for the long run.

I regularly buy furniture that uses recycled wood from a vendor called OLD ASHIBA in Japan. They have a long article with photos that was prepared as a result of some customers not completely understanding what “recycled wood” meant which lead to a mismatch of expectations.

We too have experienced this situation where a customer purchased a Smart Doll and mentioned that as a maker of fashion dolls, the body surface should not have imperfections - even though we had communicated that imperfections are embraced through our design philosophy. This customer had a poor customer experience because we didn’t make enough effort to highlight the handcrafted nature of our products - now however, customers are obligated to understand what they are buying into through an obtrusive popup that appears before they head to the checkout ;-)

Smart Doll is a handcrafted product and will continue to be made by humans until Skynet becomes self aware. Folks who seek perfect products made by Terminators should seek other brands.

The next section “Cortex or Vinyl” outlines the pro’s and con’s of Cortex and Vinyl - please read before making a purchase decision.

Cortex is compatible with all vinyl busts which will provide extra poseability for neck and arms.

Cortex or Vinyl?

There are already some misconceptions about Cortex which I would like to clarify. Cortex is not simply a cheaper version of Smart Doll. Recapping on what we previously discussed:-

Cortex parts are inexpensive but mold costs are very expensive.

Vinyl parts are expensive but mold costs are inexpensive.

Cortex is not simply “a vinyl version with seam lines” - the material and properties are different than vinyl.

Cortex is not inferior nor superior to vinyl - it has its pro’s and con’s depending on your needs. To better understand, let’s compare both the vinyl and Cortex version of Smart Doll.

Cortex parts have seam lines while vinyl does not. Cortex parts are hard and sturdy. Injection molding enabled us to design the inside of the parts too which latch onto the internal frame. This gives the body a much more sturdy feeling.

When Cortex parts are snapped together, there are parts which have a more snug fit than others meaning that there will be non-uniform gaps on the body. For example the gaps on the left side of the torso may be wider than the right side. 

With slush casting however, we can only control the outer form of the vinyl parts meaning that they just cover the internal frame instead of latching onto it. This gives vinyl its slight wobble.

Both vinyl and Cortex attract scuff marks when something is rubbed against their surface like fabrics or a fingernail etc. Scuff marks are more noticeable on Cocoa vinyl and all skin tones in Cortex. Scuff marks are easily removable with fine grit sandpaper.

Seam gaps are non-uniform across the body

If you drop a Smart Doll by accident, the first thing that will happen is that their heads will do a 360 turn before they start to scream. Depending on the floor surface, heating a vinyl part with a hairdryer may remove any dents. However any dents or deep scratches on Cortex would be difficult to remove unless you are a modeler where you would fill in the injury with putty and sand down before applying paint.

Cortex is more resilient to fabric staining than vinyl - but not invincible. While most stains (depending on how much time has passed since the stain) on Cortex can be removed with a rub of paint thinner, stains on vinyl are very difficult to remove.

Folks who come from a modeling background who have experience making Gundam models or Airfix kits will prefer Cortex - the material properties allow it to be modified and painted.

If you are going to have your Smart Doll fully dressed most of the time then where available choose Cortex - you won’t know the difference unless you roll up their sleeve or trouser leg to look for the seam lines. If you want to dress up your Smart Doll in dark clothing then choose Cortex - you can rub off most staining with paint thinner - but depends on degree of stain and how much time has passed since the stain. Remember that Cortex is not invincible to stains.

Legs can only bend at knees 90 degrees and when sitting the shins will cross

As vinyl is soft and squishy, you will get an extended range of motion. For example, as the vinyl bust is soft, the neck will be able to bend sideways back and forth - this is not possible with Cortex. However you can swap out the Cortex bust for a vinyl bust as they are fully compatible. Knees on the vinyl version kneel back slightly more than the Cortex version due to the squishiness.

As mentioned previously, scuff marks on all skin tones for Cortex show up more prominently - use the fine grain sandpaper included with all Cortex bodies to remove them - you need only brush against the surface very lightly. Be careful with zips on garments and boots - they can cause deep scratches which you cant get rid of - use stain prevention leggings and socks.

All pre-assembled Cortex Smart Dolls will be glued. If you need to change the shell on the shin or shoulders for whatever reason, you will need to break apart the shell. Vinyl however allows you to heat and remove these parts easily.

Soft Vinyl is a shape-memory polymer that can (most of the time) return to its original form after heat has been applied to it but Cortex will deform and remain deformed.

Cortex retains our Wabi-Sabi design principles - notice the birthmark on the botty.

Cortex and Wabi-Sabi

The injection molds are initially made by CNC (Computer Numerical Control) machining and then manually polished by a human which naturally creates uneven surfaces that one would expect from an organic form. Just like vinyl, blemishes ( birthmarks, stretch marks, non-uniform surfaces ) are introduced at random during the molding process and will be included on every single Smart Doll that we ship. While they look similar, no two will ever be the same.

For the Cortex heads, because we wanted to retain the same shape and keep all of the irregularities of its vinyl counterpart, we actually CT (computerized tomography) scanned the vinyl head and used the data to create the injection molds.

Read more about our design philosophy - actually its a requirement ;-)

When fully clothed you just wont be able to tell the difference between vinyl and cortex.

Cortex Q and A

The most frequently asked questions are “when is blah available as Cortex?” and “when are the kits available?” If you hear other folks ask the same then direct them to this post to view the latest schedule as follows. Dates subject to change at anytime to favor quality.

2019/??/?? Cortex Complete (Mirai Anniversary, Gaia) soft launch (very limited numbers)

2019/05/20 Cortex Hybrid Mika Jougasaki pre-orders open

2019/05/31 Cortex Hybrid Mika Jougasaki shipping starts

2019/??/?? Cortex Complete (Mirai Anniversary, Gaia, Melody) official launch + shipping

This is the schedule so far - if what you want is not on the schedule then wait until it is ;-)

Smart Doll - designed for the family. Photo sent in by @iva5rova on Instagram

Cortex and the future

The introduction of Cortex completely changes everything for us and I believe that it will create a new market for fashion doll kit modeling. Ultimately I want to have licensed Smart Dolls available as a Cortex kit too which will enable us to pass on savings to the consumer.

We will still continue to make vinyl dolls for the foreseeable future but the evolution of Cortex will continue to create alternate timelines in ways which we are not aware of yet.

With Smart Doll, the future is in your hands.

Families dropping by Mirai Store Tokyo to get their goodies.

Mirai Store

If you are visiting Tokyo then drop by our flagship store Mirai Store to check out our cortex girls on display.

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