What is KBS Premium Body Filler?
KBS Premium Body Filler is a lightweight, polyester reinforced auto body filler for light filling and finishing on steel, galvanized steel, aluminum and polyester surfaces. KBS Premium Body Filler mixes at 100 parts base to 2 to 3 parts activator, is ready to sand after a 30 minute cure, and finishes smooth enough to eliminate the need for finishing glaze.
100 : 2 to 3
Base to Activator
30 Minutes
Cure Before Sanding
1/4 Inch
Maximum Thickness
45°F to 110°F
Surface Temperature
KBS Premium Body Filler is designed specifically for light filling and finishing. The smooth, self-leveling formula spreads easily, reduces sanding time and eliminates the separate finishing glaze step, so the repair goes to primer and paint sooner.
KBS Premium Body Filler is formulated for faster working and is clog free, tack free and pinhole free. Superior sanding performance makes it ideal for cutting time and labor on every panel, which is why professionals all over the USA trust it in their shops.
One step from filler to primer: no finishing glaze, and it feather-edges without clogging your sandpaper.
KBS Premium Body Filler bonds to bare steel, electrozinc coated steel, galvanized steel, aluminum, polyester surfaces and KBS 2K DTM Build Primer. KBS Premium Body Filler should not go over thermoplastic finishes or wash primers. Every surface must be clean, dry and sanded with P40 to P80 grit before the filler goes on.
- Bare steel: Sand to clean metal with P40 to P80 grit, clean with KBS Klean, and apply the filler once the panel is 100% dry.
- Galvanized and electrozinc coated steel: KBS Premium Body Filler adheres to zinc coated steel without a separate primer.
- Aluminum: Excellent adhesion to aluminum panels and parts.
- Polyester surfaces: Bonds to polyester surfaces.
- KBS 2K DTM Build Primer: Approved as a base for the filler when the repair is built over primer.
- Over RustSeal: On rusted metal, seal the rust with RustSeal first, then apply the filler using one of the three body filler over RustSeal methods.
- Not for: Thermoplastic finishes and wash primers.
KBS Premium Body Filler combines a lightweight, polyester reinforced body with a smooth, self-leveling formula. KBS Premium Body Filler spreads easily, holds on vertical panels, sands without clogging the paper, and leaves a pinhole free surface that needs no finishing glaze, which removes a full step from a typical dent repair.
- Super smooth formulation: The self-leveling formula spreads into a smooth layer with less sanding afterward.
- Extremely easy to spread: Lays down with steady spreader pressure and wets out the surface completely.
- Incredible vertical hold: Holds in place on vertical panels such as doors, fenders and quarter panels.
- Polyester reinforced: Tough and durable once cured, yet easy to sand and shape.
- One step application: Eliminates the need for finishing glaze, so you go from filler straight to primer.
- Excellent feather-edging: Feathers out cleanly and will not clog up sandpaper.
- Multi-substrate adhesion: Excellent adhesion to multiple substrates, including galvanized steel and aluminum.
- Pinhole free, tack free and stain free: A clean surface that is ready to prime.
- Lightweight and fast working: Formulated for fast working and fast drying, so the job keeps moving.
To apply KBS Premium Body Filler, mix 100 parts base with 2 to 3 parts activator to a uniform color, press a thin first layer firmly into the clean, sanded metal, then build up in layers slightly higher than the surrounding panel, never thicker than 1/4 inch. Let KBS Premium Body Filler cure 30 minutes, then sand with P40, P80 and P180.
- 1. Prep the surface
- Remove loose debris, grease, oil, gasoline, rust and dirt. KBS Klean is the ideal surface prep. Sand with P40 to P80 as needed, rinse, and make sure the surface is 100% dry.
- 2. Measure and mix
- On a clean mixing surface, measure 100 parts base and add 2 to 3 parts activator. Mix to a uniform color, then spread the mix out on the mixing surface to break any air bubbles introduced while mixing.
- 3. Apply a thin first layer
- Apply a thin layer with steady pressure for maximum adhesion, making sure the filler wets out the surface completely.
- 4. Build in layers
- Add filler in layers, building the damaged area slightly higher than the surrounding surface. Total thickness should not exceed 1/4 inch.
- 5. Cure and sand
- Allow 30 minutes to cure, then sand in sequence with P40, P80 and P180. If more filler is needed, blow off the area with clean, dry compressed air before the next layer.
- 6. Clean up
- Clean tools with KBS #1 Thinner or lacquer thinner before the filler hardens. Wear protective gloves to avoid skin contact.
Conditions: Do not apply KBS Premium Body Filler if the surface temperature is below 45°F (7°C), above 110°F (43°C), or within 5°F of the dew point.
KBS Premium Body Filler comes in two kits, and each one includes its activator: the Quart Size Kit holds 750 ml and the Gallon Size Kit holds 3 L. The Quart Size Kit suits spot repairs on one or two panels, while the Gallon Size Kit suits multi-panel projects and shop use.
KBS Premium Body Filler kit sizes
| Kit | Contents |
|---|
| Quart Size Kit | 750 ml of filler with activator |
|---|
| Gallon Size Kit | 3 L of filler with activator |
|---|
Mix only what you need: Measure out just the amount of base you can spread, then add activator at 2 to 3 parts per 100 parts base.
Pro Tip: Store KBS Premium Body Filler in a ventilated place out of direct sunlight, between 40°F and 90°F, and keep the lid tight between jobs.
KBS Premium Body Filler differs from a typical filler and glazing putty repair in that KBS Premium Body Filler finishes pinhole free and smooth enough to skip the glaze coat entirely. A typical repair sands the filler, skims a separate glazing putty over it to fill pinholes and scratches, then sands again before primer.
KBS Premium Body Filler compared with a filler plus glazing putty repair
| | KBS Premium Body Filler | Filler plus glazing putty |
|---|
| Products to buy | One kit, base and activator included | A filler kit plus a separate glazing putty |
|---|
| Layers before primer | Filler layers only | Filler layers, then a glaze skim coat |
|---|
| Sanding | P40, P80, P180, then prime | Sand the filler, apply glaze, sand again |
|---|
| Pinholes | Formulated pinhole free | Glaze is used to fill pinholes in the filler |
|---|
| Sandpaper loading | Will not clog sandpaper | Varies by product |
|---|
A separate glazing putty is still the right tool when the only job is filling pinholes or fine scratches on a panel that is already primed. For holes or rust-through that need strength, no light filler is the answer: use a fiberglass reinforced repair such as KBS Patch.
Body filler is one step in a repair. Here is the full KBS sequence from bare metal to finished panel.
- Step 1: KBS Klean
- Clean the repair area of grease, oil and dirt, rinse, and let it dry completely.
- Step 2: RustSeal (rusted metal only)
- Body filler is porous and does not stop rust. Seal rusted metal with RustSeal first so the rust is sealed under the repair, not trapped there.
- Step 3: KBS Premium Body Filler
- Fill, shape, cure 30 minutes, and sand P40, P80, P180.
- Step 4: KBS 2K DTM Build Primer
- A 4:1 urethane build primer rated for body filler, with excellent sand scratch swelling resistance and topcoat holdout.
- Step 5: Topcoat
- Finish the panel with your topcoat. Over RustSeal, use an opaque, UV stable topcoat such as BlackTop, KBS Top Coater or KBS MAXX.
Shop KBS 2K DTM Build Primer
KBS Premium Body Filler Directions
Suitable surfaces, mix ratio, layer thickness, sanding sequence, cleanup and storage.
Read Directions →
Body Filler Over RustSeal: 3 Methods
Three ways to give filler a surface it can grip once rusted metal is sealed.
Read Article →
How To Prepare Metal Before Body Work To Prevent Future Rust
Prep and seal patch panels and repair areas before body filler goes on.
Read Article →
A Body Repair Method That Keeps Rust From Coming Back
Why rust returns after body repair and how to seal it out under filler and paint.
Read Article →
How to Fix Hidden Rust in Rocker Panels and Cab Corners
Find and treat the rust that hides in rockers, cab corners and body seams.
Read Article →
Body Filler, Putty and Patch
Compare KBS fillers, NuMetal epoxy putty and KBS Patch for every kind of repair.
Shop the Category →
Have questions before you buy? Find answers to the most common KBS Premium Body Filler questions below, or
order KBS Premium Body Filler now.
Body fillers generally fall into four groups: standard polyester fillers for general dent repair, lightweight polyester fillers that are easier to sand and shape, epoxy fillers for heavy duty and moisture prone repairs, and plastic fillers made to bond to bumpers and trim. KBS Premium Body Filler is a lightweight, polyester reinforced filler for light filling and finishing on metal and polyester surfaces. For an epoxy repair, KBS sells NuMetal Epoxy Putty.
For light filling and finishing, a premium finishing grade filler saves a step over a standard filler. KBS Premium Body Filler spreads smooth, feather-edges without clogging sandpaper and finishes pinhole free, so no finishing glaze is needed before primer. For holes, rust-through or gaps that need strength, no light filler is the right tool; a fiberglass reinforced repair such as KBS Patch is.
No. Body filler builds up and shapes a damaged area in layers, while glazing or finishing putty is a thin skim coat applied afterward to fill pinholes and fine sand scratches. KBS Premium Body Filler is formulated pinhole free and smooth enough to eliminate the separate finishing glaze step. Epoxy putty, such as KBS NuMetal, is a different product again: a hand mixed repair putty that hardens like steel.
KBS Premium Body Filler is a lightweight, polyester reinforced body filler made for light filling and finishing. The smooth, self-leveling formula spreads easily, holds on vertical panels, sands without clogging, adheres to steel, galvanized steel and aluminum, and finishes smooth enough that no finishing glaze is needed, so the panel goes to primer sooner.
On a clean mixing surface, measure 100 parts KBS Premium Body Filler base and add 2 to 3 parts activator. Mix until the color is uniform, then spread the mix across the mixing surface to break any air bubbles introduced while mixing. Mix only as much as you can spread.
KBS Premium Body Filler needs 30 minutes to cure before sanding. Sand in sequence with P40, P80 and P180. If the area needs more filler, blow it off with clean, dry compressed air and apply the next layer.
Total KBS Premium Body Filler thickness should not exceed 1/4 inch. Start with a thin layer pressed firmly into the surface, then build up in layers until the repair sits slightly higher than the surrounding panel, and sand it level.
Yes. KBS Premium Body Filler can be applied to steel, electrozinc coated steel, galvanized steel, aluminum, polyester surfaces and KBS 2K DTM Build Primer. Do not apply it over thermoplastic finishes or wash primers. Clean the surface, sand with P40 to P80, and make sure it is 100% dry first.
Yes, and on rusted metal RustSeal should go on first, because body filler is porous and does not stop rust. Apply the filler while the final coat of RustSeal is dry to the touch, usually 3 to 6 hours; or let RustSeal cure at least 24 hours and scuff it with 320 grit; or let it cure at least 24 hours and dust it with Fusion Self-Etching Primer, then wait about 30 minutes before the filler.
KBS 2K DTM Build Primer is rated for body filler and goes over the sanded repair. KBS 2K DTM Build Primer is a 4:1 urethane build primer that resists sand scratch swelling, sands easily wet or dry, and gives the topcoat a light grey base with excellent gloss holdout.
