I will thin my laminating epoxy depending on the job at hand but never more than 10% .The pictured airplane, when laying up the fuselage had the epoxy thinned and when glassing the wings and stabs as well. The fuselage layup is 1.4oz surface cloth followed by a layer of 3.6oz cloth, 1/32 contest balsa and a final layer of 3.6oz. Very light layup. The IPA used will slow pot life and cure time.