Filler after scuffed epoxy question

[cstrom72]

So after spraying a 2 coats of Epoxy over the sandblasted Mustang I'm getting around to doing some filler work. I scuffed the areas needing filler with 180 to prep for the filler (the epoxy has cured for about a month). I'm assuming that since the 180 grit scuffed epoxy will be efficient grip for the filler from what I have read and that I have a few small spots where the bare metal is just barely showing through from scuffing. I know in a perfect world it should be re-sprayed with epoxy then filler applied within the 7 day window but its wintertime and cold here and spraying really isn't feasible I don't think. I also know that people have been putting the proper fillers directly to bare metal. Will I be ok doing some light filler work where the bare metal is just barely showing through with out worry? Maybe I'm answering my own question here but since the areas where I'm getting the metal to show are both at 180 grit I'm assuming the filler will stick and stay correct? Just curious because the instruction on the Rage filler I'm using says sticks best to 36-80 grit but obviously people are not sanding the cured epoxy with that because it would get down to bare metal instantly. Let me know what you guys think! Thanks!

 

[crashtech]

Anywhere the metal is exposed, then covered with filler, is a potential site for future corrosion. It won't really affect the job in the short term, though. What you are experiencing is why I recommend a light sanding with 180 finished with red scotchbrite, which will be much less likely to break through. If you think the car is going to live a fairly pampered life, free of rock chips and poor weather driving, it will never be an issue.

 

[cstrom72]

Anywhere the metal is exposed, then covered with filler, is a potential site for future corrosion. It won't really affect the job in the short term, though. What you are experiencing is why I recommend a light sanding with 180 finished with red scotchbrite, which will be much less likely to break through. If you think the car is going to live a fairly pampered life, free of rock chips and poor weather driving, it will never be an issue.

It's my brothers 67 Mustang which has probably only been driven 3000 miles total since 1989 haha. I'm sure he will drive it more once its all redone but it will definitely always be garage kept and never driven in snow or weather. I was just concerned with the filler getting a good bite to the metal that had 180 grit scratches. Thanks Crash!

 

[crashtech]

Just pay attention to the featheredges when you sand. If you see the filler pulling off or flaking at all at the edges, you have a problem and need to start over. Have fun!

 

[cstrom72]

Just pay attention to the featheredges when you sand. If you see the filler pulling off or flaking at all at the edges, you have a problem and need to start over. Have fun!

Noted! Thank you! Far the featheredges sanded nicely and no ill signs so far!

 

[bomccorkle]

Just a future heads up you can always get out a brush and just brush some on if you just have a couple little spots and don't want to get the Gun out.