Rust repair patches

[DusterDaddy]

I have completed welding in my patches in my deck lid and door skin. The car itself has original 1974 paint that will stay on the car when it gets its new paint job.
My question is, after I use the flap wheel to smooth out the welds, do I prime with epoxy first then do my filler work, or does the filler go on bare metal?

 

[68383GTS]

Most fill first then prime.

 

[72ScampTramp]

Start with a coat of dura glass. This will fill pin holes and such and is water resistant unlike normal plastic fillers.

 

[MTmopars]

Can't tell you how the modern pros do it, but we made sure to put filler on roughed up bare metal. The old man is old school. He was painting and doing body work before he met my mother in 68. Did it off and on until the 90's.