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Getting plumbing and heating trim remade
Knobs, handles, covers, caps and dials for taps, showers, radiator valves and thermostats that are no longer made. Anything that holds water pressure, gas or mains power stays with a plumber or engineer.
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Taps, showers and heating controls are often fitted for decades, and the range is discontinued long before the valve inside wears out. The part that breaks is usually trim: a cracked tap handle, a lost shower diverter knob, a split cover cap or a thermostat dial.
Those are reasonable jobs for a maker, because they do not hold pressure. The valve, cartridge and everything behind the wall are not: they belong to a plumber, and anything on a gas boiler to a licensed gas engineer.
Parts makers commonly remake
- Tap and shower handles and knobs that push onto a splined spindle
- Shower diverter knobs and temperature-dial covers
- Cover caps and indicator buttons (hot and cold)
- Radiator-valve head covers and caps (not the valve body)
- Thermostat and timer dials and covers (not the electronics)
- Shower-rail brackets for the curtain rail, not grab rails
- Towel-rail end caps and spacers
Materials and processes
PETG
Bathroom trim that gets wet and warm (Prusa: suitable below 80 °C).
Resin
Fine splines and detailed knobs, finished and painted or plated by the maker.
Machined brass
Handles and knobs where the original was metal and gets heavy use.
ASA or polycarbonate
Covers near warm radiators and pipes.
Don't have these remade
- Valve bodies, cartridges, washers and anything that holds water pressure
- Pressure-relief and safety valves on boilers and water heaters
- Any part of a gas boiler, gas fire or gas pipework
- Mains-powered thermostat, pump and electric-shower parts
- Grab rails and anything a person leans on
- Parts in contact with drinking water
Buy certified originals for these and have them fitted by a qualified person. The safety page explains why.
Try these first
- Find the brand and range: it is often printed on the handle, the cover or the cartridge.
- Ask a plumbers' merchant: generic and adapter handles exist for many spline sizes.
- Check whether the cartridge is still sold; if it is, the matching handle may be too.
If nobody sells the part at a sensible price, a maker is the next step.
Good to know
In Great Britain, work on gas appliances and installations must be done by a Gas Safe registered engineer; other countries have similar rules. A maker should only ever be asked for trim on the outside.
Count the splines on the spindle and measure its diameter: that decides whether a handle fits.
What to put in your post
- Brand and range of the tap, shower or control, if known.
- Spline count and spindle diameter, and how the handle is fixed (screw under a cap, grub screw, push-fit).
- Finish to match: chrome-look, white, brushed.
- Photos from every side with a ruler in shot, and the measurements that matter. The measuring guide shows how.
Step by step: find the model number, measure the part and photograph it for a quote.
Not sure it is a good job for a maker? Run the checker. Ready to write it up? The brief builder drafts the description for you.
Post your part on The Spool List
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Broken part in your hand?
Photograph it, measure it, post it once.
Post the part free on The Spool List. Makers quote with a price and a lead time, and the platform holds your payment until you confirm delivery.
Sources
- Lancaster City Council: gas safety, Gas Safety (Installation and Use) Regulations 1998 (accessed 12 October 2026)
- Prusa Research knowledge base: PETG (accessed 12 October 2026)
Figures are quoted as the sources state them. Spotted something out of date? The rules and schemes change often; check the source.