What is Sika MRP Soft Light Polyester Filler and why choose it
Sika MRP Soft is a universal, flexible polyester body filler specially formulated for zinc-coated sheet, aluminium and steel substrates. Based on an unsaturated polyester resin with special mineral fillers, it provides excellent adhesion on metallic supports and is suitable for medium fills and fine finishing layers. Its short drying time and easy sanding make it an efficient solution for professional body repair and industrial maintenance.
Main features
- Universal flexible putty for metallic substrates.
- Designed specifically for zinc-coated sheet, aluminium and steel.
- Suitable for medium fills and thin finishing coats.
- Excellent adhesion thanks to the selected polyester resins.
- Fast curing with a pot life of approximately 4–5 minutes at 20ºC.
- Short drying time: around 15 minutes at 20ºC or 4–5 to 1 minute with IR.
- Can be overcoated with spray polyester filler, primer or acrylic fillers.
- Available in convenient 2.5 kg and 1.0 kg tins.
Technical specifications
- Chemical base: Unsaturated polyester resin and special mineral fillers.
- Colour: White.
- Density: 1.9 ± 0.1 kg/l.
- Mixing ratio: Mix the filler with 1–3% hardener paste. Avoid using excessive hardener to prevent problems during the repainting phase.
- Flash point:
- Filler: > 32ºC
- Hardener: > 70ºC
- Pot life at 20ºC: 4–5 minutes.
- Drying time:
- At 20ºC: approximately 15 minutes.
- With IR: from 4–5 minutes down to 1 minute, depending on the system.
- Application temperature: Above 5ºC. Do not use below this temperature.
- Storage: Store in a cool, dry place for up to 18 months.
- Packaging: 2.5 kg tin, 1.0 kg tin.
Applications and use cases
Suitable substrates
- Zinc-coated sheet.
- Aluminium.
- Steel.
- Plastic.
- Original paints or well-adhered old paints.
Typical uses
- Medium filling of imperfections and dents on metallic panels.
- Fine finishing layers before priming and painting.
- Body repair work where fast drying and easy sanding are required.
Surface preparation
- Clean the surface thoroughly with a basic cleaner.
- Ensure the substrate is dry and free from silicones, grease and wax.
- On paints, primers or fillers, sand and clean before applying the filler.
Application method
- Mix Sika MRP Soft with 1–3% hardener paste.
- Apply the mixture to the substrate using a spatula.
- Allow to dry completely; the drying time depends on the chosen system (ambient or IR).
- Carry out an initial leveling sanding with P80–P120 abrasive.
- Finish with a fine sanding using P180 abrasive.
Subsequent treatments
- Spray polyester filler.
- Primer.
- Acrylic filler.
- Tintable acrylic filler.
Tool cleaning
- Clean application tools with nitro solvent or cleaning solvent.
FAQ
On which substrates can Sika MRP Soft be applied?
It can be applied on zinc-coated sheet, aluminium, steel, plastic, and on original or well-adhered old paints.
What is the correct mixing ratio with the hardener?
Mix the filler with 1–3% hardener paste. Avoid excessive hardener to prevent problems during repainting.
How long can I work with the mixed product?
At 20ºC, the pot life of the mixture is approximately 4–5 minutes.
How long does Sika MRP Soft take to dry?
At 20ºC the drying time is about 15 minutes. With IR drying systems, the time ranges from 4–5 minutes down to 1 minute, depending on the system.
At what temperatures can I apply the filler?
The filler must be applied at temperatures above 5ºC and should not be used below this temperature.
What sanding process is recommended?
After drying, first sand with P80–P120 to level, then finish with P180 for a smooth surface.
How should the surface be prepared before application?
The surface must be clean, dry and free of silicones, grease and wax. On paints, primers or fillers, sand and clean before applying.
How long can Sika MRP Soft be stored?
When stored in a cool, dry place, it can be kept for up to 18 months.
Transport information (Section 14)
Consultar ficha técnica del fabricante.
Individual protection measures (Section 8)
Consultar ficha técnica del fabricante.
