Originally Posted by TucsonJay
I don't personally use epoxy... so I don't have an opinion about that combination.
I would call a tech line, and speak to a company techie about it.
when you use an acid product (even etch primer) fillers (bondo) wont stick too well You can even blow the filler off with an air blower...epoxy sticks very well to it so you would want to treat the bare metal and rust then epoxy ,then use the filler on the epoxy.
Epoxy alone wont stop rust even if its wire wheeled and cleaned up well ....sand blasting might clean it up enough to use epoxy alone but personally I dont think its enough and to be totally honest I dont think the guys out in the dry desert climates or the guys that build the high dollar restos know for sure either since none of those cars ever see any weather and they are always in a garage and if ever driven only on the nicest of days.....I'll bet I can epoxy over active rust and put the car in the shop and it'll never come through either but leave it out in the weather and its a whole different story.
Just for the record using a pump spray bottle works fine (never use a paint gun) but use a paint mask with charcoal filters the same type you would use when spraying acid etch primer or todays paints..I would think just the label "ACID " would be cause for caution a reading the directions....