The pink foam is undoubtedly a polystyrene foam, but it sounds like you are using a polyester or vinylester based resin where you are mixing MEKP as a catalyst.  That will melt polystyrene on contact.  While vinylester resin is acceptable, you can't use it over a polystyrene foam.  It does work with polyUrethane foam.  If you have polyester resin, you shouldn't be using it at all.  Use an epoxy based resin as it will not react with the foam.  If you read the plans, you should be using a slurry of microballoons mixed with epoxy resin to a peanut butter like consistency as a base over the foam to lay up your glass repair over the holes.  It's all in the plans for building the plane.
-Jeff Scott
Cherokee Village, AR
On 8/26/2018 7:23 PM, Lee Shook via KRnet wrote:
> I put resin on the foam and it started to deform. Kinda at a stand still.


Sounds like you need to contact the builder and get info on what
materials he used.  Sounds like a compatibility problem.  That one is
beyond my ability to help.  Pink foam that deforms with epoxy contact,

What was used to do the original layup?

Larry Flesner

Search the KRnet Archives at
Please see LIST RULES and KRnet info at
see to change 
To UNsubscribe from KRnet, send a message to

Reply via email to