I have been scheming this doorbell for quite a while. As you may know I scheme quite a bit. This one has finally come to fruition for one reason: I decided to scrap the plan to buy the expensive bits and decided to build the whole thing with stuff we have stashed around the house.
This doorbell handle releases a marble that rolls down a run, making a noise on the way. The first half is completed - enough to get it to chime!
The bell pull is an old road bike brake, pulling a tensioned chord to the marble release.
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The release mechanism is an angled hole drilled in a block of scrap wood. It is held under tension by a bundle of elastic bands, all mounted on a bit of old Ikea desk. Enamelled copper wire provides the feed mechanism and stabilises the release.
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From here part of a toy marble run (yes I know, definitely cheating) transfers the marble over to the rest of the bell.
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When I say bell, I really mean acoustic bass guitar. It had been gathering dust in the back of a cupboard for too many months. No modifications have been made to the guitar - it hangs from the bracket (a pair of old shelf supports) and everything else is suspended around it.
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To catch the marble a plastic scoop is made from an old water bottle, upturned and supported by a length of wire coat hanger.
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This then feeds into a section of bamboo sushi mat (used once for making felt) that directs the marble onwards.
And that is it for phase one. A single "ding". Keep an eye out for part two!