Realistic Verdigris - A Tutorial

There seems to be a bit of a trend in Games Workshop painting at the moment for using verdigris on anything they can. For those of you not familiar with the term it is the greenish tarnish that appears when copper (or any copper-alloy) oxidises. It is the same effect as silver tarnishing, or iron rusting. I believe if you want to paint something properly you need to understand it first, so this post will explain the Chemistry behind the effect, and the resulting colours, and then look at a technique I've developed for getting quick convincing results.

From Wikipedia (its OK, we're only after generalisations, its not a scientific paper!) "Verdigris is a complex chemical mixture of compounds, complexes and water. The primary components are copper salts of acetate, carbonate, chloride, formate, hydroxide and sulfate. The secondary components are other metallic salts, acids (organic and mineral), atmospheric gases and water. All the components are in an ever-changing and extremely sophisticated electrochemical reaction equilibrium that is dependent on the ambient environment."

So its enough to say oxidisation is a complex process for copper due to the different copper compounds which have different colours. Therefore the actual colour of verdigris will vary depending on conditions. I'm going to lay out some very general principles to help choose the right colour.

The main component is Copper(II) Carbonate, which is the characteristic light green colour. This will be your starting point for verdigris representation.

Copper (II) Carbonate

If the copper/brass is on a ship's instruments etc and exposed to salt water it can instead be Copper (II) Chloride. This is interesting as Copper (II) Chloride is a brown colour, but as it absorbs moisture it becomes Hydrated Cooper (II) Chloride which is a bright green colour. So depending on how old it is it will likely get more vivid.

Anhydrous Copper (II) Chloride

Hydrated

A darker green component is Copper (II) Acetate, which is formed in the presence of acetic acid, which is present in small quantities in fruit, particularly fermented, or over-ripe fruit, but also vinegar.

Copper (II) Acetate

Finally of interest is what happens when Copper (II) Carbonate is heated. if exposed to temperatures of ~300oC it turns to Copper (II) Oxide and this is pretty much black.

So to put this into practice; if we were weathering a brass cannon we would want a grass green colour, but blackened near the mouth of the cannon, and near the fuse. If that cannon is on a ship it would be a much brighter green, and if the cannon was on the walls of an industrial city it may be darker.

Games Workshop in their tutorials almost always use a thinned down mix of Hawk Turquiose and Dark Angel Green, which I think looks a little flat and unrealistic. As a general rule I like to use pigments for weathering, rather than thinned washes as the end texture is much better and you naturally get irregular application which looks less contrived. MIG & Forgeworld are two notable manufacturers of pigments, but most of their ranges focuses on mud, dust and rust. Originally modellers used artist's pigments/pastels for weathering, so I have returned to this principle and I have a stick of soft pastel pigment from Hobbycraft (~99p) - #165 from Faber Castell.

I scrape a small amount into a palette with a knife blade so it is a fine powder and then mix with MIG thinner for washes.





Then wash this around the brass/copper component that needs weathering. The painted surface means the thinner will flow around recesses by capillary action. The thinner can be used to control the thickness of the application and hence the final colour. By adding more neat thinner to the model you can "lift" off some of the pigment, or spread it around, making it more or less translucent.

I should point out, although specially designed thinner gives a good result, other thinners such as ordinary water, water mixed with dishwasher rinse aid, turps etc can all serve fine.

I believe for a single application technique this gives much better results than washing with thinned paints. These Mantic skeletons have had their telescopes painted with GW Shining Gold mixed 2:1 with GW Scorched brown. Highlighted with a quick drybrush and then weathered using this technique.

You can hopefully see in this last picture (especially if you click to look at the full size version) the different finishes you can get by just applying the pigment thicker (Right).

Obviously there are a number of pastel greens available and by mixing these along with black or brown (either modelling pigments or pastels) different effects such as the previously mentioned "marine verdigris" would be achievable.

I should say this technique is probably only suitable for table-top standard painting, where it has advantages over washes, but for display models a more involved technique would probably be best. I understand Vallejo do a range of washes for representing verdigris, which involves 4-5 stages of different coloured washes, but I think that is probably not justified for basic minis.

Let me know if you've found this tutorial useful - comments are the lifeblood of a blog!

Thanks. Simon

Making the most of Pendraken Ancient British Chariots

A while ago I picked up a couple of packs of Pendraken Ancient British chariots off Ebay as I fancied painting something a bit different and I also thought that with my Carthage Gallic allies, Imperial Roman skirmishers and Roman Light Horse I could probably put together a small proxy British (or Celtic Irish) force for Warmaster Ancients.

The individual components of the chariot kit are fairly well detailed (for Pendraken), but when I put them together as a dry-fit there seemed to be two obvious missing parts - an axle, or at least axle-stubs on the chariot frame to attach the wheels to and a yoke or some kind of harness to attach the chariot to the team of two horses. Looking at the Pendraken site and other pictures of the models online it is obvious that these two parts are not part of the model. You are just meant to glue the wheels to the frame and leave the horses and chariot hanging and hope no-one notices!

As I was primarily doing these as a modelling/painting project I decided to convert these chariot by scratch building the missing parts, so that the finished article was a bit nicer. This is a step-by-step of the process as I know it is a fairly popular kit.

1) The base of the chariot is about 8mm, to attach the wheels I used a piece of florist's wire about 11mm long. The wire is is about d=0.9mm.

2) There is a small indent in the back of the wheel, you just need to clean this up with a pin-vice really, not drill to any depth into the hub, final depth of hole ~1mm.



3) dry-fit wheel, chassis and wire axle, then glue axle directly to base of chariot and attach the wheels. This pictures shows the axle, underneath the frame on a finished chariot



4) now you need to make a yoke to attach the horses. The exact dimensions will depend on how you are basing them, but I used another piece of 0.9mm florist's wire (which is fairly bendy) about 23mm long. You need to bend the wire into an elongated "M", with the backs of the horses in the top of each arch and the shaft from the chariot in the base of the central "V".



5) I haven't done any research on Ancient British chariot harnesses, I've just gone for what felt right, so you may want to vary the exact shape of this yoke.

6) Finally assemble the rest of the model. I found it was better to first glue the two horses down and the yoke over their backs, let this set and then glue your chariot sub-assembly from (3) to the base and the yoke. This is mainly because you have a very small area of contact between the round chariot wheels and your figure-base compared to the size and weight of the assembly, and being able to rest/glue the front of the shaft to the solid yoke helps keep it stable while the glue dries. You can also gently file down the bases of the wheels to give a flatter contact surface to glue to the base, but be very careful not to overdo it! Lastly attach the chariot team.

These ones of mine just need the chariot crew painting up now before they are ready to go.



I hope this has been useful, if so leave me a comment to let me know. ;)