Production on M35A3 hoods for the US Army was done by Sioux Manufacturing Corporation located in North Dakota utilizing a modified Hetron 980 thermoset resin. The resin contained 10% MFA and 25% styrene, as opposed to the standard 35% styrene content. The hoods were constructed via the VARTM process at ambient temperatures and were infused in 50 minutes with the MFA modified thermoset resin. The production was deemed an immediate and complete success.
Rigorous testing of these hoods commenced to ensure the suitability of the finished properties. Elastic deflection, durability testing and impact resistance were done on these hoods. Testing requirements mandated that the hoods demonstrate no deformation, no fiber separation, and no visible cracks or broken fibers.
M35A3 hoods built with the MFA modified thermoset resin passed all testing requirements with performance nearly identical to that of hoods built with standard resin.