How do I repair a chip in a bath?

The two materials behave differently. Acrylic is coloured through a few millimetres of its thickness and takes a filler repair well. Enamel is a thin glassy layer fused to steel or iron, and once it is breached the metal underneath is exposed.

What you'll need

• A two-part bath repair kit in a matching colour
• Wet-and-dry paper in several grades
• Acetone or methylated spirit
• A polishing compound and cloth

Step by step

1. Identify the material.Tap it. Acrylic sounds dull and feels slightly warm; enamelled steel rings; cast iron is dull, very heavy and very cold. The repair is the same but the urgency differs.
2. Deal with any rust first.On an enamel chip, any rust on the exposed metal must be removed completely and the metal treated before filling. Filler over rust lifts within months.
3. Clean and degrease the area.Wash with detergent, rinse, dry, then wipe with acetone or methylated spirit. Bath surfaces carry soap and body oils that stop anything bonding.
4. Key the edges of the chip.Lightly abrade the chip and a few millimetres around it with fine wet-and-dry. A polished surface gives the filler nothing to hold.
5. Mix only what you need.Two-part fillers have a short working time. Mix small amounts on a scrap of card and work quickly.
6. Match the colour before committing.Most kits include tints. Mix a little, put a dab on an inconspicuous spot, and let it cure — wet filler is not the colour it dries.
7. Fill slightly proud in thin layers.Deep chips need building up in layers with curing between, otherwise the filler sinks and stays soft in the middle.
8. Cure fully before sanding.Follow the kit's timing, usually several hours. Sanding soft filler tears it out of the chip.
9. Sand flat through the grades.Start at around 600 grit wet, then 1000, then 2000, keeping everything wet and working only on the filler rather than the surrounding surface.
10. Polish to match the sheen.A cutting or polishing compound brings the sanded area back to gloss. This step is what makes a repair invisible rather than obvious.
11. Keep it dry while it cures.Do not use the bath for at least 24 hours, longer if the kit says so.

Tips

• Do the colour test on a hidden area and let it fully cure. Colour matching wet filler by eye almost never works.
• Repairs on the base of a bath, where feet scuff, last less well than on the sides. Expect to redo them eventually.
• For a large or highly visible area, professional resurfacing is a real option and gives a far better result than filler.

Common mistakes

• Filling an enamel chip without treating the rust — Rust continues to spread under the filler, lifting it and expanding the damaged area. The metal has to be clean and treated before anything goes on it.
• Sanding the surrounding original surface — You cannot restore the factory finish once you have gone through it. Keep the abrasive on the filler and feather only the last few millimetres.

If it doesn't work

Questions people ask