Radiator hook

Overview

*** DO NOT PRINT WITH PLA FILAMENT TO AVOID MELTDOWN ***

Update 2012-12-27:Enhanced durability with an extended fixation ring for greater stability.

This hook is designed to hang towels and clothes on horizontal radiators with a 24mm tube diameter to dry and warm up.

Bathroom radiators are usually the warmest, driest spot in the house, which makes them the obvious place to hang a damp towel or a hand-washed piece of clothing, except most radiators are not designed to hang anything from at all, the horizontal tubes are round, smooth, and offer nothing for a towel to grip onto without sliding straight off. I wanted a simple clip-on hook that could grab that round tube securely, without clamps, screws, or anything that would mark the radiator’s paint.

There are two different versions:

“down”, with the opening facing downwards. This is more robust, but it can be applied only to top tubes.
“side”, with the opening facing sideways. This is less robust, but it can be applied to every tube.

Who knew a hook could inspire such creativity in my wife? The bathroom radiator is now a quirky work of art!

Small, repeatable parts like this one are also a good match for keeping a printer running efficiently between bigger jobs: a hook or two tucked into a corner of an unrelated print’s bed can fill otherwise wasted plate space, so a spare is essentially free the next time you print something else entirely.

It’s recommended to use PETG, ABS, or ASA filament material to prevent the hook from melting due to the high temperature of the radiator.

This is not a theoretical warning; it is the whole reason for the all-caps note at the top of this page: PLA starts softening at temperatures a hot water radiator can genuinely reach, especially in the middle of winter with the heating running at full blast, and a softened hook loses its grip and lets go of whatever it was holding, right onto the floor or worse. PETG, ABS, and ASA all have a meaningfully higher heat deflection temperature, which is why they are the only materials I recommend for this print despite PLA being the easier one to work with day to day.