Will Bondo Work Without Hardener?

Without it the bondo won't get hard. Put a small piece of bondo on a board and run a line of hardener from end to end. It will take about five minutes to mix it up and apply it. If it starts tacking up, stop applying it or you'll mess it up.

Do I need hardener with Bondo?

How Much Hardener Do You Add To Your Body Filler? You need to be sure to add the right amount of hardener to your Bondo; adding more than enough will cause your body filler to dry faster and give you less time for shaping and laying your filler on your panels.

Does Bondo resin dry without hardener?

Does Bondo cure without hardener? Bondo doesn't “dry”; it cures through a heat-generating chemical reaction between the resin and hardener. In theory, properly mixed Bondo can be applied in any thickness, but beware of gravity-induced sagging.