GOODING GD-30 2K Automotive Primer Surfacer with GD-31 Hardener 4kg Sandable

GOODING GD-30 is a two-component primer surfacer system used with GD-31 Hardener for automotive repair and refinishing preparation. It is designed to sit between the prepared substrate and the final compatible color or clear coat system.

For body shops, the primer’s role is to help refine a repaired panel after filler sanding, improve the uniformity of repair transitions, and provide a sandable base before finishing. It is intended for stable, dry, hardened, and properly sanded surfaces—not as a replacement for correct metalwork, body filler application, cleaning, or sanding procedures.

Compared with premium-priced refinish systems, GD-30 is positioned as a cost-conscious option for workshops seeking a defined 2K application process. Compared with entry-level 1K primers or inconsistent solvent primers, it is designed for use as a crosslinked two-component undercoat system, subject to correct preparation and application.

After body filler has been cured and sanded, small pinholes, fine scratches, and shallow transition marks may still be visible. GD-30 is intended to build a sandable primer layer that helps the operator refine these remaining minor defects before applying finishing coats.

A properly applied and evenly sanded primer surfacer can help provide a more consistent substrate for compatible basecoat, direct-gloss topcoat, or clear coat systems. Final gloss, color appearance, and surface fullness depend on the complete paint process.

The stated sanding reference is approximately:

This may support scheduling in repair facilities with controlled drying or baking capacity. Confirm actual curing before sanding.

GD-30 is applied in 2–3 coats with a recommended film thickness of 40–60 μm. Following the stated flash-off time can help support a controlled coating process and avoid excessively wet film build.

Actual reducer selection should consider the real panel temperature, booth ventilation, humidity, spray speed, equipment, and the workshop’s validated process.

GOODING GD-30 is intended for automotive refinishing work involving:

• Collision-repair panels after body filler repair and sanding
• Local repainting of doors, fenders, hoods, and other vehicle panels
• Used-car refurbishment and aged-paint restoration projects
• Repainting over sound, hardened, and sanded existing paint
• Full-panel or full-vehicle refinishing preparation
• Properly prepared bumper or plastic repair parts within a compatible plastic coating process

• Hardened and sanded old paint films with sound adhesion
• Compatible, cured, and sanded primer coatings
• Fully cured and sanded body filler / polyester putty
• Properly repaired automotive body panels

Remove failed paint, loose material, grease, wax, silicone, dust, and moisture before application.

Mixing ratio by weight: 4 : 1 : 1.5–2

Mixing ratio by volume: 3 : 1 : 1.5–2

Use clean measuring equipment. Mix the material thoroughly until uniform. Do not use unmeasured proportions.

1. Clean and Prepare the Surface

The substrate must be dry, hardened, stable, and properly sanded. Use a professional degreaser to remove wax, grease, oil, silicone, and other contaminants. Remove sanding dust before spraying.

• Mix and Adjust Viscosity

Mix GD-30 with GD-31 Hardener and the selected G-series reducer. At 23°C, set spray viscosity to 20–24 seconds with a Ford Cup No. 4.

• Set Up the Spray Gun

Actual settings may need adjustment for the specific gun model and local operating conditions.

• Apply 2–3 Coats

Apply controlled, even coats with suitable overlap.

• Coats: 2–3
• Recommended film thickness: 40–60 μm
• Intercoat flash-off: 5–10 minutes at 23°C

Avoid heavy wet coats and excessive one-pass film build.

• Allow Flash-Off Before Baking

If using a baking process, allow the panel to stand for 15–20 minutes before increasing temperature.

• Cure, Sand, and Reclean

After the coating has reached suitable sanding condition, sand according to the next compatible finishing system. Clean the surface again before applying color coat or clear coat.

• GD-30 is not designed to replace body filler for deep dents, major pinholes, or structural damage.
• Do not apply over weak, peeling, damp, oily, waxed, or poorly adhered coatings.
• Apply a suitable adhesion-promoting primer first when the selected plastic repair process requires one.
• Do not bake immediately after spraying; follow the 15–20 minute standing period.
• Avoid excessive film thickness, insufficient intercoat flash-off, or sanding before adequate cure.
• Final performance depends on substrate preparation, mixing accuracy, film thickness, curing, sanding, compatible topcoat selection, and workshop conditions.

1. What is GOODING GD-30 used for?

GD-30 is used as a sandable 2K primer surfacer in automotive repair and refinishing, before applying a compatible topcoat system.

• Does GD-30 require GD-31 Hardener?

Yes. GD-30 is designed to be used with GD-31 Hardener according to the stated mixing ratio.

• What can this primer be applied over?

It is intended for stable, hardened, and sanded old paint films, compatible primer layers, and fully cured, sanded body filler.

• What is the correct mixing ratio?

By weight, mix GD-30 : GD-31 : Reducer at 4 : 1 : 1.5–2. By volume, use 3 : 1 : 1.5–2.

• Which reducer should be selected?

Use G-1 Reducer below 25°C. At 25°C or above, use G-2 or G-3 Reducer, subject to actual workshop conditions.

• How many coats are recommended?

Apply 2–3 coats, targeting a recommended total film thickness of 40–60 μm.

• How long does GD-30 need before sanding?

The stated reference is about 3 hours at 15°C, 2 hours at 23°C, or 30 minutes after 60°C baking. Always verify that the actual coating has cured sufficiently.

• Can GD-30 be used directly on a plastic bumper?

It may be used only within a suitable plastic repair system after proper cleaning, preparation, and the required adhesion-promoting primer step. Confirm compatibility before regular production use.

Packaging

• GD-30 Primer Surfacer: 4 kg/can, 4 cans/carton
• GD-30 carton size: 34.2 × 34.2 × 20.3 cm
• GD-31 Hardener: 1 L/can

Storage

Store in original sealed containers at 5–35°C. Keep in a dry, ventilated area away from direct sunlight, heat, sparks, flames, and incompatible materials.

Shelf Life: 2 years under recommended sealed storage conditions.

Safety

This product contains organic solvents. Use in a properly ventilated spray area and wear suitable gloves, eye protection, protective clothing, and respiratory protection as required. Consult the relevant safety documentation before handling, storage, transportation, or disposal.