Flocking Plastic

Introduction

Hard plastics such as high impact polymer, PVC, etc. are ideal for terrain boards and terrain features because they tend to be more durable than expanded foams and plaster coated wooden boards. There are now an increasing range of plastic terrain features appearing on the market from various manufacturers, including our own Hexon terrain.

“How do you get the flock to stick to your plastic terrain? “
“What glue and flock should I use?”
“Do I need an electrostatic device to apply the flock?”

These are questions I am constantly asked by gamers and model makers wanting to construct and/or flock their own terrain. For this reason I thought it would be a good idea to write a brief feature outlining some of the important points involved in successfully flocking plastic terrain. At first it can be very frustrating and the results can be variable. However, once you have a little ‘know-how’, it can be pretty straight forward and you can achieve excellent results.

First things first...

Surface Preparation
It is always a good idea to wash plastic products in warm soapy water, rinse and then dry, to remove any release agent residue that could be present on the surface.

Next either, abrade the surface of the plastic with course or medium grade glass paper to provide a physical key for the glue, prime with a thin coating of plastic primer or paint with a suitably coloured matt paint, which will adhere to the plastic and act as a primer.

The colour of the plastic or paint under the flock is crucial to the final appearance of the flocked surface. In my experience it is far better to choose a light brown, such as Dulux® ‘Salisbury Stone’ rather than a green as the base under-flock colour. After all, grass grows out of earth… and in temperate climates that’s usually brown!

Glue
I have found the best adhesive to use for flocking is Polyvinyl Acetate (PVA), often referred to as ‘wood glue’. PVA has excellent wetting properties, and when dry, grips the flock fibres with real strength. Unfortunately PVA glue has a shelf life and is susceptible to low temperatures. So if the glue has been sat in a cold garage or shed through the winter, or possibly the last three winters…DO NOT USE IT. Buy some fresh glue from a trusted supplier with a good turnover of stock. Use a quality PVA and not one of the economy brands which may have a reduced strength. Thin down very viscous PVA with about 10% water, so that when applied with a brush it spreads evenly and quickly. Speed of application is very important because the flock or scatter material must be applied before a ‘skin’ has a chance to form on the surface of the glue. This ‘skin’ will prevent the fibres from bedding into the surface resulting in a shiny slightly bald finish!

Flock – Scatter Material
There are many different types of flock available from a host of manufactures. These range from coloured sawdust, powdered foams, through to hair thin fibres known as static grass. It is the latter which in our experience provides the most realistic results. If you want to match the colour in the future, it is a good idea to chose a flock from a major manufacture such as Noch® or Faller® . You will then be able to match the colour many years later when extending your terrain or adding new features.

Silver sand is a good scatter material and it is very cheap and readily available from garden centres and DIY stores. Dry it thoroughly in an oven at a temperature of 100°C. Whether or not you inform your other half that you are cooking sand is entirely up to you. Use your discretion! Once cooled, sift the sand to remove any larger impurities before use.

Application Method
Apply the PVA glue as above. Using a sift simply sprinkle the silver sand over the desired areas, then sprinkle the static grass over the remaining surface.

The mixture creates a gradual transition and a realistic effect. Tap against a board or side of the container to remove excess flock and sand. Then place the flocked terrain on a level surface and leave to dry over night in a warm environment, i.e. room temperature or warmer. It is vital that the PVA glue is kept warm at this drying stage, or the final result could be patchy and disappointing.

A note about electrostatic application of flock.
In my experience there is no need to electrostatically charge the flock fibres during application. Excellent results can be achieved without this additional expense.

And Finally...
Once dry any residual loose flock can be removed by brushing with a firm paint brush or preferably a vacuum cleaner with a brush attachment. By collecting the flock in the dust receiver it is easy to recycle the flock ready for re-use.

The finished hill feature, ready for use!

Health and Safety Note:

Always follow manufacturers instructions on the safe and correct use of adhesives. When using flocks and small particulates we always recommend the use of a face mask