Fiberglass Filler

[Duke 48]

Would I be creating problems using West Systems 407 Low-Density filler to thicken my polyester resin? I have some imperfections in my plywood substrate I want to correct before I lay on the fiberglass mat. I'm not looking to add strength. I just do not want to have an area that the mat would bridge leaving a gap between the mat and the substrate.
Duke

[Benz]

Go ahead and do it. The filler will not react adversely with the polyester resin. Bondo would do just as well for this, if it's cheaper, since it is compatible with polyester resin.
Have fun

[Shanaly]

1 the rule i know is the one i remmeber as a 'pyramid' - you can put one pack on 2 pack, but not the other way around.
2 you can extend 2 pack epoxy with glass balls (International Epiglas per exemplum), talcum powder, or cement. the latter are miles cheaper. and the mix gets stronger....

[Duke 48]

Thanks for the replies. I had some 407 left over from another project and decided to use it. No additional cost to me.
Duke