Filler didn't harden - now what?

Damn this sucks. I smeared a skim coat of body filler on my tail section and it aint hard. This was over 30 hrs ago. Not enough hardener!

In past I have usually run out of hardener before the can ran out, so I was trying to be more sparing, now I'm screwed.

It's almost hard in some places but I can scrape a deep groove with my fingernail easily.

Any chance it'll harden if I wait a few days?

the outside might get hard but it probably wont harden evenly and cause problems later,id say start over:(

how to get it off? cant sand it - too soft, scraping will be horrible.

the tail is a custom part made from fiberglass mat. so the surface i applied the filler to is very rough and uneven. dammit this pisses me offff!!!!!!

how much is on there?

thickest is about 4mm. i guess i can scrape the bulk, but then all the stuff between the fibers ... think contact cleaner will cut it?

it will not get hard it will aways be kind of sticky use a medium grad sand paper and take it out .

try some heat like out of a blow dryer, then sand it off and start again

this happined to me a long time ago, i was lucky to have a presure washer at hand but it was on a metal body, im not sure what your workin with and will it take a beating, if not a srub bush and 30 mins of your time, there is no easy answer for this one sorry.

I could be wrong on this but I think this might work. Back when I ran a body shop we used to mix fiberglass resin with bondo in order to make it thinner so that air bubbles wouldn't form in the bondo. This would lessen the need to use spot putty to fill small pinholes in the work. Since fiberglass resin can be thinned by adding acetone possibly after you scrape all the uncured bondo off that you can, if you take a rag soaked in acetone you may be able to remove the remainder by wiping. I can't say with 100% certainty that this will work but you might want to try it on a small section and see what happens.

Nelson wrote:

thickest is about 4mm. i guess i can scrape the bulk, but then all the stuff between the fibers ... think contact cleaner will cut it?

maybe a scotchbrite pad will work.

acetone sounds like a good idea. i already tried contact cleaner and carb cleaner, neither did much. aaaaaarrrrrgghghgh !! i'm so pissed at myself . just another squirt of harender woulda done it.

ive used acetone on metal parts with no problem,but ive also seen it eat certain kins of plastics.be carefull out there!