Enamel Paints for Railway Modellers

by Chris Rabson

If you build a kit, or even modify a ready-to-run model to make it a little different from all the others in the shops, the chances are that you will need to paint some part of your latest masterpiece.

Until legislation catches up with us and water-based hobby paints become the norm, “enamel” paint is usually the choice of modellers. It can be applied by brush or suitably thinned it can be sprayed through an airbrush. For a modest sum you can even obtain authentic coloured paint backed up by years of research and development, matched by computer to ensure consistency. (I am not sure how, but that is what they say.)

Perhaps I am a little unusual in that I find the subject of model painting interesting, and feel short-changed if a constructional article skims over the details of the paint finish in a sentence or two. As the saying goes, a good model can be ruined by a bad paint job, and a poor model can be improved by a good paint finish. I think that the painting stage is the most exciting part as it brings a model to life, but like most things in this hobby, don’t expect perfection the first time – and don’t rush it. This article attempts to give an overview of the main makes of enamel paints available to railway modellers in the UK, as well as a few tips for getting the best results out of them.

Why Enamel ?

Enamel paint is fairly tough and resistant to handling and knocks: an important consideration for rolling stock which may get taken to exhibitions, or is otherwise subject to frequent handling. Enamel paint is usually colourfast (it does not change colour with time). Although solvent-based, the vapours are far less nasty than those from cellulose paint, and enamel paint is more forgiving than cellulose if applied in sub-optimal conditions. Acrylics paints marketed for models, such as Humbrol’s range, don’t stand up to repeated handling as well (but are ideal for scenic work).

We are also quite spoilt for choice of enamel paint in the UK at the moment, with two competing ranges of railway colours. There is nothing comparable in a water-based acrylic range (but some of the acrylic aerosol car paints are worth looking into). Similarly, cellulose paint, where available, is only available in a limited number of colours (unless you happen to have contacts in the motor trade).

Which Paint ?

At the time of writing (summer 2003), there are three widely- used and widely-available brands of enamel model paints in the UK:
Humbrol, RailMatch, and Phoenix Precision. In terms of availability and covering power, Humbrol is hard to beat, as well as being the cheapest per millilitre. However, “authentic” railway colours are no longer sold, and some experimentation is needed to get a close match to a specific colour. The range encompasses more than 100 colours in matt, satin and gloss finishes, as well as the useful “Metalcote” colours. All colours are available as 14 ml tinlets, with certain colours (mainly gloss) also sold in 50 ml tinlets. (Probably for painting garden gnomes, if you are into that sort of thing!) A few of the more popular ones also come in 150 ml aerosol spray cans. Humbrol is the first choice for weathering colours if you are a fan of Martyn Welch’s “The Art of Weathering”.

When it comes to “authentic” colours, RailMatch is an established presence in the hobby, having been the sole supplier of enamel railway colours in the early 1990s after the competition faded away. The range now contains colours for pre-grouping, grouping, nationalisation, and current privatisation eras. It is a synthetic enamel, produced by HMG Ltd for Howes Models Ltd, supplied in a 15 ml screw-cap glass jar. (Some colours are also available in a 150 ml aerosol spray can.) Suitably thinned, excellent results can be achieved by airbrushing. When used for brush-painting, I have found the paint more difficult to work with — it appears to be thick but goes “off’ quite quickly. It can be thinned to improve the brush flow and prolong the working time, but then two coats are invariably required for adequate coverage. Most colours have a finish that is said to be “eggshell”, but it seems to be slightly glossier than Phoenix Precision’s “dull”.
Phoenix Precision paint is probably more widely available than RailMatch – many traders sell it at the Warley National exhibition, for example. The range of railway colours is even more extensive than RailMatch, and all colours are available in both 14 ml and 50 ml tinlets. Larger sizes can be made to order if you have bigger projects. The paint is “synthetic coach enamel”, but covering properties do vary with the colour — reds seem to be especially transparent. It takes longer to touch-dry than either Humbrol or RailMatch, which is particularly apparent when brush-painting. Certain colours are supplied as matt, otherwise the 14 ml tinlets are “dull” finish, which results in an eggshell-like sheen that may not be to everyone’s liking. The 50 ml tinlets are available in either dull or gloss where applicable.

In terms of personal preference, Humbrol is by far the best for brushing, and usually covers with a single coat. Ever since the days of Airfix paint in small glass bottles (remember those?), I have disliked paint sold in screw-top containers, and RailMatch’s safety tops can make it nearly impossible to get at the paint if some has dried on the threads. Fortunately, a work-around for this is to decant RailMatch into empty tinlets: Phoenix Precision sells them, and they can also be obtained through Squires.

Storage

In his book “The Finishing Touch”, Bob Shephard (of Phoenix Precision Paints) recommends that the rims of tinlets be cleaned of dust, otherwise you are likely to draw dust into the paint when the lid is
opened and the paint will be contaminated. All good advice. I go one step further, and keep my tinlets in old biscuit tins — the sort of things that shortbread and chocolate biscuit assortments are sold in around Christmas time. Not only does this keep tinlets all together and free of dust, but it also serves to minimise the chance of a paint smell if you keep your paints indoors. I find that a typical biscuit tin will comfortably hold around 49 of the 14 ml (Humbrol) tinlets. (Look out for the deeper biscuit tins, which will take 50 ml tinlets as well.)

I don’t know what the shelf-life of enamel paint is, but provided it is kept in an airtight and cool environment, it can be used for many years. I have some tinlets of Humbrol enamels going back more than 20 years, and while I would be hesitant to use them in an airbrush, they still perform satisfactorily when brush-painted. To maintain the shelf-life, I take care to avoid getting paint on the inside of lids and rims of tinlets. This means that I do not shake paint containers, or pour paint from them: I try to keep them upright at all times. Once the openings become gummed up with paint, the lids do not make an airtight seal, and eventually the paint thickens and becomes unusable. Encrusted tinlets can sometimes be rescued by carefully scraping off dried paint, and cleaning off newer paint with white spirits and kitchen towel so that the seal can be restored, but prevention is better than cure as they say.

Thinners

The solvent used to dilute the consistency of the paint is referred to as “thinners”. In general, you should use the same brand of thinners as paint. The synthetic enamels
such as Phoenix Precision and RailMatch can be thinned quite successfully with white spirits, but I have had bad experiences when using white spirits and Humbrol enamels. However, genuine turpentine (not “turps substitute”) works very well with older Humbrol enamels, but I have not tried it with the newer Humbrol “Super Enamel” range. Treat the newer Humbrol “Super Enamel” thinners with care: it is fine as enamel paint thinners, but I have found that it will attack the carrier of some waterslide transfers, and turns the surface of some plastic kits white. (So avoid getting it on plastic glazing.) Do not use cellulose thinners with enamel paints!

For airbrush spraying, the usual thinners can be used, but both RailMatch and Phoenix Precision also sell quick air-drying thinners which are claimed to dry as much as six times faster than normal thinners. I have only used the Phoenix Precision version, 50 I can’t comment on the RailMatch product, but it does seem to work as advertised. A paint-spraying tip from an old Alan Gibson catalogue is to thin paints with lighter fluid. Once again, I have only tried this with Phoenix Precision paints, and I can attest that the results are impressive — but avoid trying this in warm and dry summer weather if you want a smooth finish because the paint does not have a chance to “flow” before the solvent evaporates.

For all cleaning-up operations, brush care, etc., I use cheap and cheerful white spirits and kitchen towels. When I have finished, the bottle of white spirits and the used kitchen towels are taken out of the house, as the smell is not particularly pleasant, and the vapours doubtless do nothing positive
for your health.

Paint Preparation

It is tempting to take your jar or tinlet of paint, shake it for 15 or 20 seconds, and then open the cap or lid and use the paint as it is on your latest project. Six hours later, you wonder why the paint is still tacky, or the colour doesn’t seem quite right. Merely giving the paint container a “good shake” is simply not enough.

After learning the hard way (several times), I do not “shake” my paint at all. Instead, after carefully removing the top of the paint container, I use a Tamiya paint spatula (available as a pack of two from Squires) to stir the paint. This is done slowly by hand to make sure that the various components of the paint are fairly evenly mixed together — you can usually tell when there are still “lumps” of pigment at the bottom of the container. Once the stirring has produced a fairly even consistency, I follow this with about 20 seconds of agitation from the battery-operated Badger paint-mixer (also available from Squires), which does a good job of final mixing.

“The Finishing Touch” recommends the use of a piece of bent piano wire mounted in the chuck of a mini-drill as a paint-stirrer. Unfortunately, my Minicraft drill speed is fixed at something like 12,000 RPM, and after a near-disaster with Humbrol Lining Orange in the living room, I decided I needed something a little less enthusiastic. The Badger battery-operated device does the job once any clumps of pigment have been broken up by hand-stirring. When the paint is well-mixed, it is ready to be used. If I am brush-painting, I will use the small “ladle” on the other end of the Tamiya paint spatula to transfer roughly the quantity of paint I think I need to a ceramic multi-compartment artists’ mixing palette. I can -then add thinners to suit, and/or mix in other 7 colours for weathering purposes. If I am air-brushing, I will transfer a quantity of paint (clean plastic drinking straws make cheap disposable “pipettes” — dip one end -in the paint, put a finger tightly over the 7 other end and lift) into a clean glass screw- 7 cap jar, and then mix in appropriate thinners to bring the consistency of the paint to that of milk.

Varnishes

Although strictly beyond the scope of this article, I ought to say a few words about varnishes. If you are painting items of rolling stock, chances are that you need to 7 letter and number them, and most of the time transfers are the obvious solution. -Once applied, it is common practice to protect the transfers from being rubbed off through repeated handling by coating them I. with a thin layer or two of varnish, most often matt or satin. Humbrol, RailMatch -and Phoenix Precision all supply their own brands of model varnish in matt, satin and gloss — even special varnish thinners in the case of Phoenix Precision. Humbrol matt varnish slightly thinned with genuine turpentine and applied with a good brush -works well to protect transfers on matt- 7 painted wagons. I have no experience of either RailMatch or Phoenix Precision varnish products.

But if you are planning on airbrush varnishing entire rakes of coaches, avoid the specialist model paint manufacturers altogether and head for your nearest DIY outlet. A 250 ml can of Ronseal satin polyurethane varnish will surely last a lifetime, and if you follow Guy Williams’(of Pendon fame) recommendation, thin it with Humbrol thinners and tint it with Humbrol matt black and dark earth to taste before running it through your airbrush. The results are superb!

This article was first published in the Autumn 2003 Double O Gauge Association Journal
All Material copyright the Double O Gauge Association 2004