Quickie Q2 Lite Construction Manual - page 38
FOAM
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Three different types of rigid, closedcel1 foam are used. A low
density (nominally 2 lb/ft3) b1ue¬white or orange, large-cell styrofoam
is used as the foam core of the wing, canard, vertical stabilizer, and
control surfaces. The blue-white or orange foam is exceptional for smooth
hot wire cutting of airfoil shapes. The large cell type used provides
better protection from delamination than the more commonly used
insulation-grade styrofoams.
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Low density 2 lb/ft3 green or light tan urethane foam is used
because it is easy to carve and contour, and is completely fuel proof.
The urethane used is Urethane 210 or equivalent.
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The white styrene modified urethane foam is used in medium density
(4-6 lb/ft3) where higher compression strength is required.
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Do not substitute foams for those supplied by Quickie Aircraft
Corporation. For example, the Q2 blue-white or orange styrofoam has great
glass surface peel strength than the standard blue styrofoam sold by some
distributors. Also, we considered using the "fire resistant" BROWN
urethane instead of the green 2 lb urethane, but found its physical
properties, fatigue life, and fuel compatibility to be much lower than
the urethane supplied to Q2 builders. Do not confuse styrofoam with white
expanded polystyrene. Expanded polystyrene is a molded, white, low