X-Surfer Plans
The least dense material I have found so far is the RAFT-R-MATEŽ product from Owens-Corning, Available at Home Depot located in the insulation department for ~$3. If RAFT-R-MATEŽ is not available, try 2mm sheets of Depron or also Zepron.  Zepron is a little more dense but can be folded instead of thermoformed. See the new directions using Zepron. Although I have never tried Depron, I believe it is made from similar material and will thermoform in a similar manner.

Step 1: Cut a piece from the RAFT-R-MATEŽ such that all folds run parallel (
fig. 1). The iron used was teflon coated (Sunbeam appliance Classic Iron - 3957) or the like. Using the iron on low (Acrylic or lower setting, about 185-190 F), iron out the corrugations to yield a flat sheet. I found it helpful to rock the fold on the iron (fig. 2) to evenly heat the spine. You can feel the material losing its regidity as it heats up. Don't force the material as it will crease and buckle, losing its regidity. Once the fold is flat enough (and before your fingers burn), iron it on a flat surface (fig. 3). Continue this process to flatten the other folds to yeild a flat piece of foam (fig. 4).
fig. 1. Cut so all folds run parallel
fig. 2. Thermoform out folds.
Fig. 4 Finished flat  piece of foam.
Comments or questions?

Copyright Phil Rossoni, 3/6/03
fig. 3 Iron fold flat
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