Can you put body filler on top of primer

Applying body filler over epoxy primer provides maximum corrosion protection for the metal. Apply filler within seven days of applying epoxy primer to maximize adhesion.

Can body filler be applied over red oxide primer?

Don’t do it. Never apply filler over any type of paint– especially over the rust-stop stuff. You will discover on the paint label that it is expected that you use the non-corrosive paint as a primer over which you apply the finish coats. Body plastic should be applied over bare metal only.

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 I put body filler over paint?

Can they be applied over paint? A. 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 primer do I use over body filler?

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. That’s what I did on the job here.

Do you have to prime over etch primer?

As a rule of thumb Self Etching Primers need another coat of primer over them to fully seal everything up long term. We suggest using a Urethane Primer over the self etching primer as a barrier between the self etching primer (Do not use Epoxy over Self Etch).

Does body filler prevent rust?

The mere application of body filler over a substrate won’t stop rust, Miller said. Fillers might contain corrosion resistance and slow the process, “but they’re not gonna stop it,” he said. Put filler on rust, and “(the rust) may continue to grow,” he said.

Can I spray epoxy primer over etch primer?

It is no longer recommended to use an etch primer under an epoxy primer. Residual acid from the etch primer can interfere with the proper curing of the epoxy. This may lead to extended dry times, potential blistering, and even adhesion failure.

Should you sand etch primer?

In any complete restoration or body repair project, you will to sand primer at one point or another. However, most manufacturers of self-etching primer, due to the acid base of the products, don’t recommend directly sanding the self-etching primer.

Can you put polyfilla over paint?

When using filler it is always good practice to thin down the first coat of emulsion when painting the surface. … We would recommend you rub down the surface and apply another coat but thin down the paint with 20% water – this will seal the surface and give a more uniform finish.

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Will primer fill in scratches?

2 Answers. A lot of times primer and paint will fill in these tiny scratches and most people will not notice even if the scratches are not filled in completely.

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.

How do you top coat a POR15?

Application: Stir POR-15 Top Coat before and during use, DO NOT SHAKE. Using a pouring spout, dispense a portion into a separate container and seal can at once, keeping lid and grooves clean. Do not paint out of can. Apply POR-15 Top Coat in two thin covering coats.

Does POR15 need top coat?

If the paint that you want to apply the POR15 over is loose, it will eventually flake off. The POR15 rust preventative must be top coated, as it is UV sensitive.

Can por-15 top coat be brushed on?

The POR-15 guys recommend some prep work for heavily-rusted projects. They also offer a spray for new or clean surfaces that’s designed to chemically “etch” the metal for better coating retention. … POR-15 applies easily and can literally be brushed or rolled right on top of existing rust.

How thick can you apply 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.

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.

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 have to Prime Bondo before painting?

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'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 prepare bare metal for body filler?

Just put the filler on the clean metal. You want the metal to have scratches so that the filler will bite onto it. We use 36 grit grinding disks to clean and texture the metal before applying filler. You can even use something as fine as 80 grit, just be sure to push the filler into the scratches so that it bonds well.

How long can I leave etch primer before painting?

Most primers should sit on a car for around 24 hours before applying the base coat of paint. Some primers may dry in as little as 30 minutes, but experts say to apply the primer 24 hours before painting for the best results.

What is the difference between primer and etch primer?

A zinc-rich primer should be used as part of a heavy-duty, high build, two-pack system. Etch primers work by acid etching the metal surface. … Whilst the etch primer should be sprayed to ensure a thin, even film, the topcoat can be brushed.

What do you put on bare metal before primer?

To properly prepare new metal surfaces, use mineral spirits to remove grease and apply a rust-inhibitive primer before painting. For painted surfaces that are in sound condition, remove dust with a clean, dry cloth, de-gloss the surface with light sanding, and wipe with mineral spirits to ensure good adhesion.

Is self etching primer necessary?

After you remove the rust scales from the metal on your car, you need to apply self etching primer. … It does, however, prevent the rust problem from worsening. You need to make sure that you apply self etching primer to bare metal that’s been thoroughly cleaned in order for it to be fully effective.

Do I need etch primer on bare metal?

Both Epoxy Primer and Self-Etch primer (Self-Etching primer) can be used on bare metal. … If you’re doing some body work and you have some bare metal, you don’t want to just put regular primer surfacer because it does not have the corrosion properties like Epoxy or Self-Etch.

Can I use epoxy primer over bare metal?

1. Over Bare, Clean Metal – Epoxy primers are amazing at sealing up bare metal and from allowing moisture or corrosion to creep in. Epoxy primer actually seals out the oxygen from the metal, leaving no chance of rust or corrosion forming on the surface like some cheap spray bomb type primers.

What's the difference between etching primer and epoxy primer?

Self etching primer bonds well to bare metal surfaces and can be top coated in a short period of time. Epoxy primer can be applied in heavy coats which can be guide coated and block sanded to remove small imperfections in the body. Epoxy primer takes longer to dry (cure) before it can be sanded or top coated.

Is etch primer epoxy?

SPI epoxy is specifically designed to be applied under filler, not so much for adhesion (filler sticks well to metal) but for corrosion protection. Filler and etch primer are both porous, epoxy is not, so epoxy provides a moisture barrier right at the metal where it’s needed the most.

How long after filler can you paint?

Run a wet finger or knife along the filled line, pushing it into the gap. Use a damp cloth to remove any excess. Allow the line to dry at least 30 minutes before taping and/or painting. If painting with oil based paint or if the joint is large, allow at least 48 hours.

Can you sand filler primer?

When dry, the surface can be immediately recoated, top coated or wet sanded. For best results, allow Filler Primer to dry for 1 hour before dry sanding. Test in an inconspicuous area to be sure Primer is dry enough for sanding. Block sand the area using 320-400 grit sandpaper.