How long does Bondo body filler take to dry?

Asked By: Yanine Gstattner | Last Updated: 12th February, 2020
Category: home and garden home improvement
4.8/5 (4,496 Views . 31 Votes)
10 minutes

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Beside this, how long should Bondo cure before sanding?

Generally, in a matter if a few minutes it will start to harden and get rubbery. At that point, you can carve it up with a utility knife, a hand planer or a bondo rasp. Just make sure you leave enough to do a final sanding, usually within 10 to 15 minutes you can start sanding it.

Also Know, why is my Bondo not drying? If the Bondo isn't dry, it's because you didn't use enough hardener or the temperature is too low. Getting it wet didn't help. Try using a heat and strip gun. It gets hot pretty quick so keep it moving.

In this regard, how long does it take for body filler to cure?

If your filler hardens too fast, you used too much, if it takes too long, you didn't use enough. You only want to mix what you can use in about 10 minutes. Properly mixed, body filler will begin to thicken in 10-15 minutes, and be fully cured in 30.

Is Bondo body filler waterproof?

Fiberglass. Choose between Bondo Fiberglass Resins, Bondo Fiberglass Repair Kits or Bondo Body Fillers. Bondo Fiberglass Resins and Repair Kits are 100 percent waterproof.

38 Related Question Answers Found

How big of a dent can you fill with Bondo?

Its OK to use bondo up to 1/4 inch. If it is your pride and joy, I'd do a little more work to reduce the dent. Using Metal-2-metal will make it a little stronger than normal bondo.

What grit sandpaper do I use for Bondo?

We usually use a cheese grater then 40 grit then 80 grit then use polyester putty then 180 grit then 220/320 then use a filler primer that is sanded with 400 or 600 before painting. A coarse grit does a better/faster job of leveling but then you need to remove the scratches.

Can I wet sand Bondo?

You can wet sand plastic body filler ("Bondo" is a trade name like "Chevrolet" or "Nike") but you should carefully heat the filler with a blow torch before priming. Just take a blow torch and quickly wave it across the filler and you will see the moisture evaporating right before your eyes.

Can you screw into Bondo?


Bondo is pretty easy to file, sand, cut and drill holes in. If the holes are for screws and whatnot, why not make the hole a little larger, sleeve it with an aluminum tube, then bondo over to hide the tube. smooth out later.

How strong is Bondo?

Bondo is amazingly strong and is very easy to work with. The mixing ratio seemed vague so I went with 8 drops per 3-4 grams, on wax paper on top of a scale.

Can you apply body filler over sanded paint?

Fillers and putties will normally work OK over properly sanded (80-180 grit) cured OEM paint. However, with so many different types of aftermarket paint available (lacquer, enamel, urethane, water-based). We recommend that all paint be removed where filler is to be applied.”

Can you put body filler on Baremetal?

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.

Do you have to prime over Bondo?

You should use a "direct to metal" (DTM) primer to help top coats stick to the metal but it's not needed under body filler most of the time. Once the metal is primed then you can apply a "filler primer" (2K) to help hide scratches and minor surface irregularities.

Can I paint over body filler?


Thread: painting over body filler
They need to be primered with a fill primer (not epoxy). If you don't prime the filler then the filler will absorb the paint, which will end up looking like a bullseye in the paint after you're done.

What is the best auto body filler to use?

The Best Car Body Filler
  1. 3M Bondo 261 Lightweight Filler. See More Reviews.
  2. Permatex 25909 Liquid Metal Filler. See More Reviews.
  3. 3M Bondo Professional Gold Filler. See More Reviews.
  4. Evercoat 156 Light Weight Body Filler.
  5. 3M Dynatron 492 DynaLite Lightweight Body Filler.
  6. Evercoat 112 Rage Gold Premium Car Body Filler.

Why do fillers crack?

There are several things that could cause the cracks in the filler. Possibly, stress, from sanding on the rest of the body, poor adhesion, moisture beneath the filler? You could even have one lower layer of filler that is curing at a different rate than the next.

Can you paint over Bondo?

Painting over Bondo. Fairly sure any primer is fine. I like a decent filler primer, with good build level, on fillers, this often covers pin holes and sanding marks.

Will Bondo harden without enough hardener?

without it the bondo will never get hard. put a lil glob of bondo on a board and run a line of hardener over the top from end to end. mix it up and apply, it should give you about five minutes working time before it starts to harden. once it starts tacking up, stop trying to apply it or you'll just mess it up.

How long does bog take to dry?


Working time varies between 3 to 8 minutes depending on temperature. For faster cure, or in cold weather, use more hardener.

What do you do when fiberglass resin won't Harden?

About the Author:
  1. Set the fiberglass in the sun. The curing of fiberglass resin is an exothermic reaction, meaning that heat makes it work.
  2. Use a heat gun on the fiberglass. If the heat of the sun isn't enough, a more intense heat source may be needed.
  3. Spray a mist of catalyst onto the fiberglass with a spray bottle.

How do you fix sticky fiberglass resin?

If You Find Yourself With Sticky Resin:
  1. If it's liquidy: scrape it off.
  2. If it's tacky: leave it.
  3. If you have areas that have cured perfectly: sand those parts down, thoroughly wiping away the sanding residue.
  4. Leave your fresh resin coat to cure for 24 hours: your piece will look good as new!