How To Do Bondo Work

Is Bondo hard to work with?

Bodywork is a slow, tedious task that takes time to master, but is easy to learn. Don’t be afraid to use Bondo, as it is a good quality product that is a must-have for any body repair project. And don’t worry if you screw up, you can always sand it off and start over.

Should you prime before body filler?

Do not proceed to Primer Filler stage until filled area is even. Adding body filler AFTER primer filler should be avoided to prevent possible adhesion, staining and shrinkage concerns.

How long should Bondo dry before painting?

Allow the putty to dry 15 minutes at 77 degrees F (25 degrees C). In cooler climates, putty may take 20-30 minutes to dry.

Do you need hardener for Bondo?

(Bondo comes with a tube of hardener.) If you add too much hardener, the mixture will gel too quickly. If you add too little, it increases the amount of time for it to cure, and if you don’t add enough it will never cure.

Can you Bondo over paint?

Bondo Ultimate can be applied directly over sanded and cured primer and paint. This filler remains easy to sand for days after the application.

What is the difference between body filler and putty?

Putty is essentially a thick paint with a filler material – it’s generally used for very small scratches where the metal is not exposed. Air hardening. Body filler is a polyester resin suitable for small dents. Chemical hardening, a cheap and easier (by a long way) substitute for body solder.

What grit sandpaper do I use for Bondo?

Make sure to sand outside of the repair area as Bondo will need to be spread and applied wider than the damaged area. (36-grit to 220-grit should do the trick for body filler application). AutoBodyNow.com sells a vast assortment of sandpapers and sanders to complete this step.

What can you use instead of Bondo?

You can use plastic/metal 2-part epoxies. Repair epoxy is also a good alternative.

What temperature should I apply Bondo?

If you’re looking for a reasonable temperature to work filler then stay above 50 deg. F. The warmer the filler gets the quicker it will harden and be sandable.

How long does Bondo take to dry without hardener?

That said, having an idea of how long bondo takes to dry is important whenever you’re planning out a project or repair. 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.

Is Bondo better than wood filler?

The biggest advantage of using Bondo over a regular wood filler is the short dry time. Wood filler can take hours to dry and require more than one coat. Bondo dries in less than 30 minutes and only requires one coat! This means more projects in less time.

How much hardener do you put in Bondo?

Mixing is the most vital step when using body filler. Plastic body filler needs the filler and a hardener mixed at the perfect ratio. The mix is crucial: 50:1.

How long can Bondo be left unpainted?

Between life and work, the longest time period the bondo would go Unpainted would be about 2-3 weeks.

Should body filler go on bare metal?

Before adding any filler, you should get the metal fairly close. For small repairs, you can bog directly over the bare metal. If the repair is larger, or you’re looking for a longer-lasting job, apply a base coat of epoxy primer before laying on the filler.

Can you put body filler over bare metal?

Q. Can Evercoat fillers be applied over bare metal? Evercoat fillers are designed to work over bare, properly prepared substrates such as: steel, aluminum, galvanized metal, fiberglass, and SMC. Fillers and putties will normally work OK over properly sanded (80-180 grit) cured OEM paint.

What comes first primer or Bondo?

The other says primer, then Bondo. Avoid endless forum threads and consult the manufacturer for the definitive answer. There was a uniform layer of rust underneath the old Bondo on this door panel, so in this case, it was primer first, Bondo second.

Can you use self etching primer over Bondo?

Yes. You can apply self etch over fully cured filler.

What happens if I dont use enough hardener in Bondo?

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.

Will filler go off without hardener?

The resin which is included in wood filler prevents the hardening by itself without hardener. Once the resin will eventually run out and atmospheric oxygen will participate to harden the wood filler even without the hardener.

Can you Bondo big dents?

Even some major dents can be treated with car dental fillers. Fillers like Bondo can crack if they are mixed too thickly, harming rather than improving the look of the car. Additionally, there’s a risk of discoloration and poor long-term wear when you use a dent repair filler like Bondo.

Do body fillers crack?

All these products are designed to move with the bumper so the material does not crack. Body filler is also not designed to adhere to a plastic surface the way that it adheres to metal. This ensures that while sanding and while the bumper moves, the material will not chip away or detach from the surface.