well i sanded my paint down to bare metal and cleaned it with acetone before applying bondo and my third batch of bondo on a dent my friend forgot to wipe down before applying the third coat of bondo on the area so there was left over sanded bondo dust on the area.

now i have painted over it already and there are some 2 quarter size bumps that just popped up from the bondo this is about 3 weeks later, i'm guessing the surface had some oil on it? or was this the sanded bondo? that made the bondo bubble up?

and if it is this how long will my bondo last before falling off? Note: bondo i on drive side door, so there will be lots of opening and closing the door.

 

did you primer the bare medal b-4 bondo or is it just bondo on bare metal? if its just bondo on bare metal you may have some moisture under the bondo> how long will it last i have no idea.

 

its probably a result of poor adhesion.

 

I would have to see it to tell you what it is.

If it was actually the brand name "bondo" that you slathered onto the bare metal, you might have some problems down the road. Meaning, that the bondo itself isn't formulated to adhere to metal. Possible nothing will happen, but you never know.

 

thanks for the input guys

 

and i did bondo over metal