What’s The Best Glue For Polystyrene / Stryofoam

Just a quick post on the what is the best glue for Polystyrene and Styrofoam expanded foam sheets, both hugely popular for making landscapes, hills and inclines.

Styrofoam and Polystyrene are some of my favourite building materials for landscapes, especially on small layouts or those in a spare room where I might not want or be able to build more elaborate hills, cliffs, and inclines from other heavier more permanent materials.

With a bit of shaping (see Where Next below for a suitable tool) and a top coat of plaster cloth very credible landscapes can be quickly constructed.

Before going further, there is a lot of confusion around these materials so it’s worth clarifying exactly what material I’m referring to here.

Is it Polystyrene, Styrofoam or Expanded Polystyrene foam?

Although often used interchangeably these terms shouldn’t be confused.

The material I’m glueing here is expanded Polystyrene expanded foam or Expanded Polystyrene (EPS).

It’s available in sheet and block format and is most often used for packaging but is great for railway, diorama and war game landscape modelling.

Typically white in colour, the expanded foam variant is made of small beads giving a lightweight, soft corky, texture. It’s easy — although messy — to work with and can be cut with a knife or hot blade (the fumes from the heating foam board are highly poisonous. This should absolutely only be done in well-ventilated areas — I do it in my shed with the extractor fan running.

If you’re interested, it’s made by expanding Polystyrene beads under heat and bonding them together.

Styrofoam meanwhile is blue in colour and most often used in building construction — for pipe insulation etc — and while it’s is often mistakenly used as a generic name for extruded Polystyrene foam it is actually the brand name for the product from Dow Chemical Company. The same glue I suggest below will work for this as well.

Injection-moulded styrene has completely different properties to the expanded foam variety. It’s a hard plastic, often in sheet form, and used as the construction material for many of the model kit buildings on layouts. I won’t dwell further on the glue for that, instead, I’ve covered it in my guide to glues.

What glue not to use with polystyrene foam (EPS) sheet

Before getting to the best glue for polystyrene I want to touch on some glues you shouldn’t use and why because many people will likely have these around at home and might be tempted to use them but doing so can be problematic, to put it mildly.

Firstly, hot glue. I use this for various projects (my miniature bird nests for example), it’s low cost and many people have hot glue guns lying around. But the heat from them will melt the foam. Both the tip of the glue gun and even the warmth of the glue as it emerges before cooling is more than enough to dissolve the foam.

Another glue, probably even more common than hot glue, is super glue. Cyanoacrylate (CA) glue to use its correct name, is tremendously strong and long-lasting so might seem like a good choice, particularly for small projects but don’t go near polystyrene (EPS) foam with it. Super glues type adhesives which will melt the foam boards like the acid blood of the predators in Aliens.

So, what is the best glue for polystyrene foam

Having experimented with different glues over the years, I’ve found this to be the best glue for fixing Polystyrene foam board and Styrofoam to baseboards and to each other — for building up layers on hills etc.

It’s easy to apply, and work with (spillages can just be wiped away), it’s cheap and forms a strong bond when set.

Another reason I like this glue, in particular, is that it’s still easy to cut through for later detailing and shaping, even once dry.

While other glues hold the foam together (No More nails and epoxy substances in particular) they can produce a very hard barrier that’s difficult to cut through later.

It’s also a good all-around glue that can be used for many other jobs around the layout (track laying, scenery fixing, water modelling etc.). I get through a lot of it so buy it in bulk using the above link.

Where next?

• You can get Polystyrene foam boards online here.
• For cutting and shaping Styrofoam and Polystyrene, I use Nordstrand’s hot wire knife.
• Fix your Polystyrene sheets and Styrofoam boards easily, quickly and now with this glue.
  

 

> A final, personal, note: I spend a huge amount of time testing, photographing, writing and researching techniques for these articles and pay for all the running costs of MRE out of my own pocket. If you found this article useful you can support me by making a donation on my fund-raising page. Thanks and happy modelling, Andy.