Additional information, history and current discussion about MPF is available on the RCGroups.com thread in the Scratchbuilt foamies forum: http://www.rcgroups.com/forums/showthread.php?t=1533245
Physical Characteristics
per sheet
Overall dimensions: 24"x47"
Thickness: 6mm max; all tolerance to low side
observed range 5.2 - 6.1mm
Weight per sheet: 5.2 - 5.25oz (147-149gm)
Density measured: 2.25lb/cuft
Cantilever Beam test
Samples were cut 32x219mm from each of three foams: Readiboard less paper skins, Dow High perf less plastic film skins, and Model Plane Foam as received. They were then fixtured for matching top surfaces and equal beam length. US pennies were placed in the same spot on each, and resulting deflection noted.
Samples in free state. left to right Readiboard less paper, Dow High Perf less skins, MPF as received
Samples deflected by 4 US pennies
total weight = 10 gm
Thickness: Readiboard - 4.0-4.3mm; Dow - 5.2-5.5mm; MPF - 5.4-5.6mm
Weights: Readiboard - 1.1gm; Dow - 1.3gm; MPF - 1.4gm
Straight view of deflected samples shows the differences
Formability test of MPF cold rolled on Bendfoam Mandrel
4"x12" samples of MPF taken from long direction of sheet and cross direction were cold rolled over a bend foam 1 1/8" dia metal mandrel. Rolling was accomplished by gentle thumb pressure to the foam in a series of 3-4 passes.
Overview of the Bendfoam fixture showing the 1 1/8" dia. EMT mandrel, and a formed piece of MPF.
both samples after forming in free state.
Note the cross board radius is smaller
Sample ends taped together. cross sheet max width = 3 9/16"; long direction max width = 3 3/4"
Close-up view showing the points of highest tension in the bend. Note no visible stretching or disfiguring of the foam surface.
