Moulding of the Edith Kramer Sculpt – Did it go to plan?

Was the sculpt dropped by accident?
No, she has just gone through the moulding process!

After sculpting Edith Kramer, it was time to mould her to create a negative copy that I could use to replicate it in a different material. This is one of the scariest points of any project!

At the Madame Tussaud’s workshop, they mould their sculpts in plaster using multiple pieces. A lot of the times plaster solely is used for moulds which is due to the longevity of the material, without the loss of detail. However, I have chosen to do a jacket mould for my mould as its purpose does not need a lot of copies to be made, therefore I could achieve the same level of detail by using silicon supported by plaster. This would also ensure a very minimal seamline – the more parts to a mould, the more chances of low-quality seamlines. This was the correct choice, as I had a very insignificant seamline in my casts that had no effect on the overall quality.

Another conscious choice I made at this stage, was the thickness of the silicon. As I was keeping the silicon in one piece, I had to think how it would affect the wax when I was pulling it off the casts. Due to this, I chose to keep it under roughly 5mm thickness on average. Consequently, there would be less chance of the surface of the soft wax becoming deformed while peeling off the mould. However, this was a difficult line to toe, as I had to control the thickness to not become too thin, which could tear the silicon.

I would also like to address the problems I predicted in the earlier stages of this project regarding this stage:

  1. I went over schedule with the sculpting by a week. Whilst I stuck to my timeplan of the project, there were some major errors with the sculpt pointed out by Val Adamson late on that needed to be fixed to meet my benchmarks. Therefore, I made an analysed decision to extend the sculpting time by using one week spare which I left for myself at the end of the project, in order to reach a certain quality.
  2. I did not smudge the details when I laid out the first layer of silicon! Have a look at this timelapse to see me using the smallest brush I had to gently ensure coverage without force.
  3. The silicon cured successfully. I am glad I used a newer batch to ensure this.
  4. There were no air bubbles formed in silicon which means no surface details were compromised.
  5. Writing up a plan for this stage was an immense help in ensuring I did not forget crucial parts of the moulding process.

Have a look below for images of the moulding process. Overall, the moulding was successful, although it was strange to see Edith Kramer’s face all smashed after she was pulled out!


Predicting Problems and Finding Solutions

Studying modelmaking for the past couple of years, I have gained an understanding into some of the various processes that are involved in the practise of making. Approaching a new project, I think it would be helpful to use this existing knowledge alongside my continual research, to have an objective look at the work ahead and predict some of the issues I will encounter. Let’s find some solutions to these so that I feel more prepared!


The armature might be too big/too small which will affect the stability of the sculpt and affect the surface sculpt.I will note down measurements of my sculpt and then work backwards to ensure the armature is the right size.
The eyes might be put in the wrong depth.Make sure the replacement eyes I am using for the sculpt are 12mm (1/2 of average eye size) so that they fit into the head. Also make sure the armature underneath is small enough so that I can dig the eyes deep enough.
The facial features and anatomy might look disconnected from each other.Work in stages following the instructions of Edouard Lanteri to achieve correct anatomy. Keep taking measurements throughout. Work on facial features all together in stages, don’t finish one before the others.
Anatomically incorrect primary shapes that make the secondary and tertiary details look wrong.Follow the instructions of Edouard Lanteri. Use a mirror and take photographs throughout to change perspective. Measurements!


I might take too long on sculpting.Make a time plan for the entire project and stick to it! Encourage yourself to keep moving throughout the sculpt to discourage perfectionist tendencies.
When I put the first layer of silicon on I might smudge the details.Pour the silicon on rather than brush it on for the first thin layer. Have a bowl underneath to catch the silicon and reuse.
The silicon does not cure.Use a newer batch that you know has cured successfully in a previous test.
Air bubbles form in the silicon.Use a vac former to reduce bubbles and pour from a distance to let gravity pop any remaining bubbles.
I forget to put the Vaseline on surfaces during the plaster stage.Write up a plan for the moulding stage to take with you into the workshop and use as a reminder to do some important tasks.


I might make the wax the wrong tint.Get in touch with industry professionals to enquire whether they would advise me on some colour combinations they use. Do test pieces first.
The oil paint tint might not mix properly with the wax and drop to the bottom.Make sure to heat the oil paint with a little bit of wax first up to a high temperature. Mix in with the rest of the wax well. Do test pieces first.
Wax might not be stored correctly which can affect quality of wax.Store in a cool, dry place away from dust.
Parts of the cast might break off when taken out of the mould.Ensure the silicon layer is no thicker than 5/7mm max.
Health and Safety – Hot wax!!Complete a health and safety assessment before casting. Ensure area is prepared before use and that others know to be careful around it. Plan beforehand. Ensure appliances are turned off afterwards.


I make the layers of paint on the surface too thick.Practise painting on the test casts before the final one. Use a dry brush and wipe off excess paint before applying. Take your time and do not rush. Look in mirror and take pictures to keep changing perspectives and
I will use the wrong tones and colours.Ask industry professional for their advice before painting. Practise by oil painting portraits on flat surface first.
My painting might not look realistic as it might not follow anatomy.Research anatomy and how light interacts with it. Research the blood vessels etc underneath the skin to understand how they will impact the surface colour.


The hair strands I will use might be too thin and fragile, or too thick and synthetic.Test out a selection of materials before hair punching final. If too thin – try hair spraying and then styling. If too synthetic – try various methods of softening them. Ask MakeUp SFX students to advise on hair choices. Confirm choices with advice from industry professionals.
Hair punch holes might look too big and obvious, particularly around the hairline and facial hair.Outsource, make and test out different needle sizes before final hair punching. Understand how deep they need to go in to be stable. Experiment whether you can melt the wax after hair punching to increase quality.
Outsourced eyes might not look realistic enough/too doll-likeHave a list of producers you can contact for replacement eyes just in case.
The clothes I will make might not look realistic as the scale of the thread might be out of place.Research how to recreate clothes at smaller scale. Look at stop-motion animation dressing techniques. Choose a clothing piece from an existing photo – keep choice simple.

Of course, there are many problems and issues that I will encounter during this project – far too many that I could write! So to manage the sheer variety of problems and to decrease the damage they may have on my time management of the project, I will construct a thorough time plan for the duration of the project. This will ensure that I know exactly how much time I can spend on each mistake and issue, and hopefully keep me on track.

Fingers crossed!

Ammonite – Making of!

Approaching the making process, I split it into six main stages:

  1. Sculpting
  2. Moulding
  3. Casting
  4. Chambers
  5. Puzzles
  6. Painting

While some of these stages had to be completed before I could move on to the next – for instance, I had to have a cast of the shell to create the walls for the chambers – they didn’t follow a strictly linear pattern. I planned so that I could be completing other stages while moulds were curing etc.

Following are images of each stage, with short descriptions of problems encountered and how they were resolved.


To start off with, I had to make the ammonite shell that would be the main body of the model. I used buff clay as it is very quick to sculpt with due to its softness.

For reference, I used an image from The Etches Collection of an ammonite in their collection.

I explored making a stand for the sculpt at the beginning in order to allow me to sculpt both sides of the ammonite. However, I quickly realised that this would not be needed as only one side would be visible. Therefore, I could rest it flat on the desk.

Sculpting the ammonite was a relatively straightforward process that was quick to complete.

Along with the ammonite shell, however, I also needed to sculpt the head and tentacles of the animal. I did not want to use buff clay for this sculpt, as it was on a smaller scale to the shell and would need more details. The tentacles would also pose a problem – due to the softness of the clay, they might be prone to moving while I sculpted, even with an armature inside. Consequently, I decided to use Monster Clay – a harder material.

I could not use Monster Clay alongside the buff clay due to the difference in softness, but I still wanted to make sure the head fit snugly into the opening of the shell. To achieve this, I held off sculpting the head until I had a cast of the ammonite shell I could sculpt into.

For reference, I used images of cuttlefish and nautilus.


After sculpting the ammonite shell, I created a mould of it using silicon. As the back would not need any detail, I could make it an open back mould.

During this process, some silicon seeped underneath the shell as it was not flush flat against the surface. I cut out the unnecessary silicon.

The head and tentacles of the ammonite had to be moulded in plaster, as I wanted to cast it in silicon later. Due to the complexity of the tentacles, the mould had to be made out of two parts.

I encountered one particular issue while moulding the second part of the plaster mould. While I made sure to plug any gaps between the styrene walls and plaster, there must have been a gap I overlooked! Some of the plaster seeped underneath, which caused the risers on that side to be covered up.

To resolve this, my first idea was to attempt to dig the risers out of the plaster once it had hardened. I quickly realised this would not be an effective way of solving the issue, therefore I decided to amend my casting process for the head and tentacles instead.


I used the silicon mould to cast copies of the ammonite shell out of fast cast resin. There were a few problems I encountered during this process.

The main issue that arose was the weight of the cast. For the mechanism to function effectively, the shell could not be too heavy, as it would impact the type of spring strength I would use. The heavier the shell, the higher strength of spring I would need in order to prevent the shell sinking straight to the bottom once placed on the spring. At that point, the puzzle pieces would not make an impact on the vertical position of the model as it would already be sitting on the bottom of the spring!

Unfortunately, I realised this was an issue after I did my first clean-out cast and felt the weight of the shell.

To resolve this, I used aluminium trihydroxide powder. The theory behind this was that the powder would replace the resin in the mixture, which would result in a lighter cast. I tested this out using my second cast – it did not make it lighter. In fact, it had the opposite effect, and made the cast even heavier!

A positive of alumiunium trihydroxide powder is that it results in a far more durable cast, so I decided to use the shell from my second attempt despite its weight. I could lighten it afterwards by taking away material from the back.

Another issue I encountered during this stage, was in relation to the magnets I planned to place in the chambers of the ammonite that would help to keep the puzzles in place. Initially, I planned to place the magnets in equal distances from each other on top of the silicon. In practice, however, this did not work – the magnets were too close together and attracted to each other immediately. To counter this effect, I poured the resin in layers and placed a magnet in each layer. This meant that the magnets were held in place as the resin cured.

While casting the silicon head and tentacles of the ammonite, I also run into some obstacles. As mentioned previously, half of my risers were accidentally covered during the moulding process. To avoid bubbles forming inside the tentacles, I did not pour the silicon into the closed mould at first. Instead, I left the two halves open and filled the tentacles. Afterwards, I closed the mould and used the vac chamber to get rid of any potential air bubbles. Lastly, I injected the rest of the silicon. This solved the issue and no bubbles formed inside the tentacles.


Firstly, I used paper to make some quick prototypes of the shape of the walls. I used these shapes as reference when I heat bent chemiwood for the walls. I used a jig – a secondary piece of chemiwood which I sanded down to the desired circular shape – to ensure the walls had the correct shape.

Using filler to create a plug for the chemiwood to stick inside the ammonite chambers was a bit tricky, primarily due to the sanding afterwards. Some of the areas were a bit tight and it was difficult reaching them. I tried using a rotary tool to get to these areas but the tool was too big. I resolved this issue by just spending more time sanding.


This was perhaps the most experimental stage of the entire making process. I encountered numerous problems as I explored how much weight I could add to resin.

I originally thought about using metal powder to weigh down the puzzle pieces, however, after researching some of these powders, I decided it would not be a cost-effective option. At this point, I considered the casting of the shell that I did earlier and remembered how the use of aluminium trihydroxide powder increased the weight of the cast.

Unfortunately, due to the size of the puzzle pieces, the powder on its own would not have made enough of a difference in terms of weight. Therefore, I considered other options and explored placing different objects inside the cast to weigh it down. I settled on using steel nuts, which combined with the aluminium trihydroxide powder, considerably increased the weight of the cast.

At this point, the steel nuts became an issue for me – they were extending out of the cast and very visible. To resolve this, I did a layer of resin around the mould, let this cure, and then placed the nuts inside. This ensured the steel nuts were not visible.

Frustratingly, casting a layer of resin around the mould first to hide the steel nuts, manifested another problem. The aluminium trihydroxide powder I was using, caused the resin to cure much slower. As I had to continually turn the mould to coat all the walls in an equal amount of resin, the increased curing time meant I was turning the mould for an unnecessarily long time. Consequently, I chose to use purely fast cast for the outside shell layer, which cured much faster. I still used the powder to bulk out the inside layer of the cast.

A final issue I encountered was when I was dying the resin. The multiple layers of resin meant I had to ensure that they all had the exact same shade of blue. I was forced to spend extra time while mixing the resin each time to match the shades. Unfortunately, this meant that the resin would start to cure by the time I would get the shade right. To resolve this, I made note of how much of each pigment I was using per 12ml of resin (the average amount per layer) which helped to mix the right colours much faster.

Magnets were also added to each cast to correspond with the magnets placed in the shell.

Lastly, some interesting notes from this stage:

  • The alumiunium trihydroxide powder made the resin more gooey for longer (due to the slower curing time). This meant that bubbles were more likely to form in my puzzle pieces as the steel nuts trapped some air inside. The effect of this can be seen in two of the photos below, where a large air bubble formed at the top of the mould.
  • The difference in curing time was particularly obvious in one of the below casts. I took it out of the mould too early, which meant the inside layer containing the powder was still fairly gooey. This cast highlights the two different layers of resin – the shell and the bulk inside.


In preparation for this stage, I kept my first cast of the ammonite shell to use as a tester. I used it throughout to experiment with different colours and airbrushing techniques.

For paint to adhere to the surface of the shell, a primer base was necessary. I tested my primer on the tester shell and realised that it would result in a cold underlayer. It also affected the paint that would go on top – it added a green tint to the yellow base coat. I used a white primer on the shell instead.

I used acrylic paints and an airbrush to paint the model. I painted the eyes and highlights with a small brush.

One of the biggest issues I encountered during this process was right at the beginning – while spraying on the first coat of my base colour, I realised the paints I was using had hardly any pigment in them. This meant that I would need far too many layers to even get a faint colour on the base. I used different paints and this issue was solved. (Pro tip – always test the pigmentation of paints!)

To build up enough pigment, many layers of airbrushing were needed. I had limited time left to apply this finish, which meant I could not get the amount of detail I initially planned to paint.

Finally, while painting the eyes of the ammonite, I found it particularly tricky to use the airbrush. Despite changing to a 0.2mm nozzle and needle, and decreasing the air pressure, I continually ended up with a ‘spidering’ spray pattern. I hand-painted these areas instead.

Overall, the making of this model was very exciting, with its fair share of frustrating moments! I enjoyed each stage in its own way, and wish I could spend a little bit more time exploring each one in more detail.