What is the best surface to mix Bondo on?

1. Mix on a Spreader Mixing Board designed for the job. Do not mix on cardboard, cardboard will absorb the important resins from the body filler and hardener. Lay down your filler and then apply the correct amount of hardener.

What can you mix Bondo in?

Cut a thick piece of cardboard about 6 by 6 inches (15.24 cm by 15.24 cm). Alternatively, you can mix it on particle board or buy an inexpensive pad of disposable plastic sheets to mix the Bondo. Open the can and mix the Bondo with a stir stick if there is a layer of liquid on top.

Does Bondo body filler need a hardener?

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.

How long should Bondo dry before sanding?

When used according to the manufacturer’s recommendations, Bondo takes 10 to 15 minutes to dry enough to form a sandable surface. After 45 minutes it’s cured enough to be painted.

What happens if you use too much hardener in body filler?

Adding too much hardener will result in rapid gelling of the mixture, making it hard to get coverage in time. Too little hardener will increase cure time, but there’s a point where the filler won’t ever harden and you won’t know it until you try to sand.

How do you keep Bondo from sticking?

WD-40 is an excellent lubricant that prevents fillers from sticking…and makes it easy to remove once the Bondo or Wood Filler is dry!

Can you clean Bondo with acetone?

Also as soon as your done with your plastic bondo spreader clean it good with acetone and they will last longer. wojojo and henryj1951 like this.

Can you Bondo over old Bondo?

Yes, you can layer bondo over bondo as much as necessary with no problem.

Does Bondo harden 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.

Why is my Bondo sticky?

It could just be the skim on the top that stays sticky. Some lower quality fillers don’t have the additives required to stop that from happening. Try sanding it, if it remains soft and clogs your paper after that first top coat has been removed then you need to take all off.