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Foam filler material for my IBIS

Foams for Aircraft Building

The plywood skins of the main wing, the canard wing and the top skin of the fuselage forward of the canopy are stiffened up by a foam product called Styrodur.
The same stuff goes into the dead spaces between the front and the back of the firewall and into a few

other places. It's put in there to prevent skin buckling without adding hardly any weight. Styrodur is distributed by Saint-Gobain ISOVER.

Styrodur 3000 S discontinued; replaced by 3035 CS

Chapter 7 of the IBIS builders manual specifies the usage of Styrodur 3000 S. Unfortunately, this product is no longer in production. I contacted a sales rep at Saint-Gobain ISOVER and had a pleasant conversation.
As it transpired, Styrodur 3000 S foam used to be produced with a gas that is no longer allowed due to current enviromental concerns over the production process. The producer changed the production process and created replacement products for the entire Styrodur product line.
The replacement product for '3000 S' is called Styrodur 3035 CS. For your convenience, you can download the Styrodur 3035 CS spec sheet here [95 KB] .

Update on foam availability

So that leaves us with Styrodur 3035CS. But does it? Unfortunately, I was't able to find a local source for just that material. Having it shipped to me would have been prohibitivly expensive, as it is very bulky for its weight. So a long search for a replacement product was initiated.
Recently I was able to source an alternative that has identical properties.
It's called "Jackodur KF300 Standard [313 KB] ", which - like Styrodur - is a solid extruded polystyrol foam. Chemically it's just the same and all physical properties are the same as well. Behaviour due to short-term and long-term loads, thermal insulation properties, moisture absorbtion over time, flameability, it's identical. Instead of Styrodur's greenish colour, Jackodur is of a rather light purple colour - other than that it is identical to Styrodur.
I don't know how Jackodur compares to Styrodur cost-wise, but at least it's available to me locally in multiple thicknesses - even in single slab quantities.

DISCLAIMER: if you decide (or are forced) to use an alternative instead of the specified Styrodur, do your own testing to establish mechanical properties and glue system compatibility. YOU are the builder in charge, your decisions should be based on your own findings, not on hearsay.
Also please note that extruded polystyrol doesn't like fuel, so don't use it for whatever other project without switching your brain on first.

2004-2012 IBIS RJ.03 "The French Canard" homebuilt aircraft project
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