Spot priming epoxy

[Chevynutz]

I need to spot prime a few spots of filler that are out of the time window, i sand with 180 but curious about adhesion of over spray out past sanded area on existing epoxy. Is this something to worry about ? Or just make sure to sand out past area to be epoxied. Seems if adhesion is not 100% the over spray will sand off anyway.

 

[Barry]

180 is perfect.

 

[Lizer]

As my own personal preference, I sand out farther than what I anticipate I will spray, and then I also clean farther out than where I anticipate I spray. That ensures that any overspray is adhered well, which is insurance in the event that it does not get completely sanded off in the next round of sanding, since that is really more of a scuff than a deep block sand for applying more epoxy.

 

[crashtech]

SOP here is to block out with a finer grit a minimum of 6" away from the area to be primed. Depending on the stage we might use 220-320 for the featheredging, in collision work where it's prime once and done, we would use 600.