Other Foam Materials

Model Aircraft Foamies

Are you browsing on the internet for information about foam materials use for building model aircrafts, but finding it time consuming and exhausting to locate the right sources?

Here in Model-Aircrafts.com, we have put together information about several more different foam materials for your convenience in finding the right foamy that can easily be used to build your own custom-made model aircrafts.

If you are a novice to foam materials, just read on and to find out more details about these foam materials before going into your own foamy aircraft project.

Different Foam Materials

Polymethacrylimide (PMI) foam: It is white coloured foam that is relatively more expensive than many other types of foam material. It is also known as ‘PMI foam’ or by the trade name “Rochacell”. The foam available in the market as precut foam sheets with thicknesses ranging from 1 mm to more than 65 mm.

Although it has an excellent compressive strength, It can be cut with a saw or hot wire and sanded easily. Unlike many other foam materials, polymethacrylimide foam does not react aggressively with most commercial solvents (e.g. acetone, styrene etc.). Because of its high compressive strength over many other types of foam, polymethacrylimide foam is often used for sandwich construction in model aircrafts or airplanes.

Urethane foam: It is a closed-cell polyurethane foam type that available in various weight densities. The foam can be lightweight and flexible or as hard as rock that a hammer is needed in order to make any visible dents in it.

Apart from being available as foam sheets, Urethane foam also available in the form of two-part liquids that when mixed together will expand into a rigid solid foam material. Accordingly it can be used to cast parts (e.g. guns, exhaust stacks, wingtips etc.) of almost any size for model airplanes. Simply create molds of the parts you want to cast and fill them with the Urethane two-part liquids and let it cure.

Another possible application of Urethane foam is by using the aerosol of such foam for repairing components such as the damaged fuselage sections of foam model aircraft.

Polyvinylchloride (PVC) foam: This is a type of rigid foam that cannot be cut with hot wire apparatus. The foam is available under different trade names (i.e. Termanto, Divinycell or Conticell) and comes with the weight densities of 30 – 400 kg/m3.

PVC foams can be sawn manually into smaller pieces of different shape and size and they are normally being used as sandwich materials for building full-size items such as the gliders etc.

Ethafoam: It is a type of low-density polyethylene foam that is similar to polypropylene foam. Two of the trade names for Ethafoam available on the market are “Ethafoam Select” and “Ethafoam Nova”.

Depron foam: The brand name of Depron in Germany is “Selitron/Selitac”. The foam is extremely lightweight, flexible and strong, and probably is the future of ultra lightweight RC model aircrafts.

Depron is a type of extruded polystyrene (XPS) closed-cell foam sheet material often used below parquet flooring to reduce step noises. It is available in two different colours (i.e. white and grey) and three different thicknesses (i.e. 2 mm, 3 mm and 6 mm). It has a density of weight comparable to that of balsa sheet.

When paints are used on white Depron foam, the applied colours come out nice and vibrant even without the foam being primed priory. However, please be certain that you are using only the water-based latex paints which are friendly to foam materials.

To assemble your model aircraft components made of Depron foam, you can use 5 min or 30 min epoxy, or any foam-safe glues such as the UHU por and odorless cyanoacrylate (CA) glues. Please be aware though "foam safe CA glues" tends to get brittle, and as a result the elasticity of foam material is reduced.

When use together with styrofoam-safe glue, Depron sheets could form a relatively strong bond with the glue due to the sheet’s high flexibility. Because of this good bond and high flexibility, the resulting model aircraft components made of Depron foam (e.g. fuselage sections) are relatively tough and virtually crash-proof.

Zepron foam: It is similar to Depron foams in many ways. For example, it too does not require to be primed prior to applying paints of different colours. It also can be shaped easily into simple shapes (e.g. wings) with a heat gun or hair dryer. However, it needs additional reinforcement to maintain rigidity, and is cheaper in price than the equivalent Depron foam.

Arcel foam: It is a composite of 70% EPS and 30% polyethylene foams. Compare to EPP foam it is not as high in compressive strength, but it is rather easier to be moulded;

Elapor foam: It is a composite type of foam material similar to Arcel foam, but made of different foam compositions. It is not as strong compressively and relatively easy to be moulded, and

BlueCor Fan Fold foam (FFF): "BlueCor" is a product brand name for a type of extruded polystyrene (XPS) foam primary used as building insulation under new sliding. It is supplied by different manufacturers (e.g. DOW, Amocor, Owens Corning etc.) and comes with a variety of colours such as blue, green and pink. It is available in foam sheets of 3/8” or 3/16” thick that being ‘fan-folded’ back and forth into different sizes.