So in the spirit of political correctness and repeating the party line ” Ideally filler should never be more than 1/8″ thick “.

How thick can you lay body filler?

There is no minimum thickness for Bondo, but there is absolutely a maximum. You do not want to apply body filler to anything that is thicker than about a 1/4”. That does not mean it can’t be done, but the repair will not last as long.

Can body filler fill holes?

Repairs rust holes up to 3“ wide in most types of metals with a fiberglass reinforced, easy to mix Body Filler for Holes. Contains two types of filler for the perfect repair of holes up to 3″ wide in most types of metal.

Can you put body filler on Baremetal?

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.

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.

Do 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. 6 Ready for Primer Filler PD-1510 when body filler is completed and the car is straight.

Why is bondo bad?

Unfortunately, filling compounds such as Bondo also present some drawbacks. 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.

Can you Bondo over rust holes?

While “Bondo” is the name of a 3M product, it has also become a generic term for plastic body filler, and several companies make similar stuff. The putty can be useful for filling rust holes in the most rust-prone areas of a car including quarter panels, fenders over and behind the wheels, and the bottoms of doors.

What comes first filler or primer?

Years ago, the accepted method was metal-filler-primer but with new technology, new products and as we learned from past mistakes we have found that the most effective and durable way to go is metal-primer-filler.

Can you Bondo over small holes?

The hard way is to weld over the holes and the easy way is to put body repair tape on behind the holes and bondo over them.

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How long should Bondo cure before sanding?

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. 7. Using 3M™ Sandpaper 80 grit, sand and shape the filled area to the contour of the surface.

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.

Do you have to add hardener to 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.

What can I use instead of Bondo?

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

Is Bondo permanent?

Bondo Body Filler cures fast, shapes in minutes and is formulated to be a non-shrinking and permanently durable material. In addition to its uses on vehicle exteriors and other metal surfaces it is also a suitable repair option for wood, fiberglass and concrete.

Can you use body filler over por 15?

CAN I USE BODY FILLER OR PUTTY WITH POR-15? Yes. First paint both sides of the rusted area with POR-15; then use body filler or putty as soon as the POR-15 is dry to the touch.

Can you leave body filler exposed?

Applying Body Filler / Bondo The application of filler material can expose you to some hazardous materials if you do not take appropriate precautions. Most body fillers contain a solvent called styrene. … Exposure to styrene can cause respiratory irritation.

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.

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.”

What is glazing putty?

Glazing putty is quite possibly the simplest element which is used in construction and fixing materials. It is regularly used in the making and fixing of window glass sheets and re-securing a displaced edge of an old pane. … The putty is really smooth as it does not shrink.

What should I spray before 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.

What grit sandpaper do I use for Bondo?

Use 60 to 80 grit paper to sand down below rust, deeper scars or to sand down and begin to shape body filler, such as bondo. These are very coarse grits and should only be used in specific areas where you really need it since it will leave sanding marks.

What's the best body filler to use?

• 3M Bondo 261 Lightweight Car Body Filler. This lightweight product is a two-part body filler. …
• Permatex 25909 Liquid Metal Filler. Unlike the Bondo filler, the Permatex product is ready to use, it does not need any mixing. …
• Evercoat 156 Lightweight Car Body Filler.

How do you Bondo a bullet hole in a car?

1. Prep the surface with a Scotch-brite pad or 220-grit sandpaper. …
2. Mix the Bondo. …
3. Use a plastic squeegee to apply the Bondo mixture to the bullet hole. …
4. Use the sun or a heat lamp to harden the filler on the car panel.

How can I fill a hole in my car without welding?

Adhesive or aluminum tape is an easy and fast solution, especially for auto body damage. You can also paint it over to hide the repair work. However, if you use adhesive tape to repair holes in a car body or any other metal type, that’s considered a transient solution.

How do you fill holes in metal without welding?

Epoxy or Tape Epoxy and tape are two common no-weld hole repair options. These do-it-yourself approaches are effective when repairing a small hole rather than a significant tear. Specialty epoxy and tape products are designed to patch steel and metal.

Can you fill screw holes with Bondo?

I used Bondo to fill the holes. After sanding with my random orbitol with 120 grit, the finish is perfect. … I started using Bondo as a nail & screw filler for paint-grade years ago when I saw a high-end painter use it.

How much hardener do you put in Bondo?

2. Place the proper amount of Bondo filler and hardener: 50:1. First, place the filler on the mixing board and then place the hardener.

How long does body filler take to set?

Bondo mixed to the color swatch will begin to cure in less than 10 minutes at room temperature. Too much hardener in a warm environment will reduce working time, but too little in a cool environment can result in maddeningly long curing times. A heat lamp can speed curing in colder weather. 4.

Can I wet sand Bondo?

Don’t wet sand filler. Filler is too absorbant and you can have problems getting it dry plus you could cause moisture to wick through to the metal or weaken the bond between the filler and the substrate.

Can you Bondo in cold weather?

I agree, you can bondo in cold weather. It will be easier if you keep the bondo warm (in your house) before you measure it out and use it. Keep the part you are going to bondo in the house also until just before you do the bondoing. The bondo will actually get warm on its own (exotherm) if it is not spead to thin.