Teardrops n Tiny Travel Trailers

Polyisocyanurate Rigid Foam Insulation Board Dose not get eaten by polyester fiberglass resin
When use poly you can use mat cost less then woven . less sand and fill
Will cure in the sun if you forgot catalyst.
you need to mark the foam to get an bite .I like holes any resin that runs down helps with sheer loads and more bite
Some are set that poly will eat all foam. Today had person wanting to fight over this.
With 4 finished trailers and 4 pods being built right in front him

Polystyrene does get dissolved by many polyester resins.

There are many different kinds though, so best advice is test compatibility with the specific materials you want to use.

Never mind arguments, just ignore the idjits and test for yourself.

Polyisocyanurate , not a foam we like using … Brittle , releases poisons when burned, not self healing … best used for insulation , not for a structure that must be somewhat flexible … Don’t trust me , try it yourself …

structure that must be somewhat flexible Had a trailer ass ended bent the light cargo door steel door frame in over 1 inch back to front The foam did have glass on two side. So it had to bow out. The only damage was at the very back where impact happen. Did not brake the foam. Foam lost bond with skin. Trailer stop car that hit it doing over 60. As the car went under the trailer bent tire rim frame fenders Yes Polystyrene does get dissolved by many polyester resins. not Polyisocyanurate May not be the best for PMF But if your building a FOAME with fiberglass skins. In picture don't see where it dissolved anything . Not say anything bad about PMF.
The combo of the two would do away with wood rot .Using glass around doors windows ,front bottom for rock hits
Yes Never mind arguments, just ignore the idjits and test for yourself.

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