Creating Pre-Heresy marines – part 3: Mark III Power Armour

Continuing the series of power armour represented throughout the Great Crusade and Horus Heresy, this next tutorial covers:

How to create Mark III power armour

Games Workshop's Mark III models, pircture courtesy of Gagoc the Ancient

Games Workshop’s Mark III models, pircture courtesy of Gagoc the Ancient

The Iron Suit (Armorum Ferrum) was created as a heavier alternative to the previous marks of armour, rather than a replacement. Due to heavy casualties from engagements aboard ships and within tunnel complexes, a more robust suit was required. The Iron Suit boasted superior frontal armour, with full plate protection, but a lighter rear to compensate and allow mobility.

Sourcing parts for this mark of armour is very easy, but will require some sculpting and stud work to complete.

The list of components is as follows:

Mark VII  / VIII legs. The most modern and arguably most common legs available.


A Chaos Space Marine or Berserker backpack.


A plain chest torso. The ad-mech chest that comes vehicle sprues is ideal here as it is easier to clean, has a row of studs on the top and piping that you can optionally leave exposed should you want to show some battle damage.


Plain shoulder pads. You can actually buy Mark II/III pads but it is a very rare piece – I believe you get a single pair per Red Scorpion set from ForgeWorld.


Your chosen armament. I will be detailing how to make a Pre-Heresy bolter as part of this tutorial.


Arms, preferably gloved.


I highly recommend using Maxmini’s Steam Knight helmets for the most suitable head option. You can ask them to send a whole pack of this type.


Crafting the armour:

Starting with the legs, they need a bit of cleaning. Remove any purity seals, wires and decorations. I also cut the slightly pointed top of the knee pads off and make them more circular.


Most of the plates need to be bulked out and made smooth. Approach one segment at a time and let the putty go hard before continuing on. Take a small piece of putty, roll it into a sausage and place it onto the thigh plate.


Use your sculpting tool to flatten and stroke the putty over the whole plate. Push it to the edges and keep stroking it to make the surface smooth. Add more putty if required, to ensure the whole plate gets coverage. The excess can be cut and/or filed off.


Once the whole plate is covered and even, smooth the putty with the flat of the sculpting tool and then let it harden. You can speed up this process by placing the model under heat – such as a lamp.


While you wait for the putty on the legs to cure and harden you can work on another piece of the model. Taking the chest, cut off and file down the chest to a smooth plate. Studs can be left on, but all insignia and the belt buckle should go.

Like the thigh plates above, roll a sausage of putty and place it across the chest. Stroke this down towards the belt.


Once you have a smooth surface reaching down to the belt, let the putty cure a little – 5-10 minutes in room temperature. Then take a knife or sharp sculpting tool and press a horizontal line into the putty a little above the belt line.


Mark two diagonal lines from here, towards the belt line.


Cut and scrape out the putt below this line, exposing the plastic underneath. Then let the putty fully cure before working further.

mwg_mk3_15If you want to produce multiple marines in this mark of armour, continue the above steps for each so that they can all cure at the same time and continue in bulk with the next steps.

View part 2.

Rusty Dice

Aint nothing but a horn

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