Lost Foam

[Bud Shupe]

:confused: What the heck is"lost foam"? I've done "lost wax"but gold and silver are much to heavy for airplanes.

[chemsurfer]

I think this web page describes how to do it better than I could... especially since I haven't done it yet. Lost Foam (favonius.com) (http://favonius.com/soaring/lost_foam/lost_foam.htm)

Brad

[Ollie]

One of the advantages of the lost foam process is that a cheap and easily formed plug is less expensive and labor intensive than building a faired, sanded and filled plug to make the female mold, when only one or two finished pieces are required. Another advantage is that the lost foam process results in a seamless finished product. Yet another advantage of the lost foam process is that you don't have to consider drift angles to get a rigid part out of a rigid female mold. A disadvantage is that a smooth finished surface is not produced automatically and manual sanding, filling and fairing are required. If you want to produce more than one or two identical finished parts, the investment in a smooth plug and female mold is the way to go.

Of coarse you could make a hard, smooth faired plug by the lost foam process and use that plug to make female molds. Then you could remove the foam from the plug and have an extra finished part which would be followed by parts made in the female mold.