How to fix an ABS bathroom fitting to ceramic tiles

Everything in a bathroom is coated in something. Soap scum, limescale and the silicone in polish sprays all sit on the glaze as a release layer, and wiping with a cloth moves it around rather than removing it. Hot water with detergent first, then an isopropyl alcohol wipe after abrading, is what makes this joint last.

The glaze itself is non-porous and glass smooth, so adhesion depends on a mechanical key. Abrading inside the footprint gives that key and stays hidden.

ABS is easy to bond once its moulded skin is taken off with abrasive paper. Do not use solvent cement here: it will bond ABS to ABS beautifully and does nothing for the ceramic side.

The last factor is water and time. Epoxy reaches handling strength in hours but takes a full day to cure properly, and water reaching a partly cured joint ruins it. Whatever the pack says, keep the shower off that wall for 48 hours.

1. Choose the position, ideally on a whole tile rather than across a grout line.
2. Wash the tile with hot water and washing up liquid to cut the soap film, rinse and dry.
3. Pencil round the fitting, then abrade the glaze inside the line with 120 grit until it is matt.
4. Abrade the bonding face of the ABS with 180 grit.
5. Wipe both with isopropyl alcohol and let it evaporate fully.
6. Mix two-part epoxy and apply an even layer to the fitting, keeping 3mm in from the edges.
7. Press it onto the tile, hold for two minutes, then tape it in place.
8. Leave the tape on 24 hours, and keep the area dry for 48.