Chosen Solution
Basically dismantled the unit to clean as hair gets everywhere, a small metal part fell out before i had the chance to take a placement photo, and now can’t quite figure how it’s meant to realign. Everything else appears to be in order I just can’t place this small metal lever which I’m guessing is what closes the circuit. Below is an image of the unit which illustrates the area where the black plastic switch is meant to slot in on the bottom of the image, along with the black plastic switch underneath the unit alongside the metal part that I cannot seem to place correctly. You can see the small metal solder on the bottom right of the motor unit, which i suspect may be what the metal ‘clip’ part is meant to close the circuit on:
Below are close ups of the actual metal part that I cannot fit correctly into the unit:
Below is an image of the black plastic switch in position within the unit:
Can upload more images if there is something specific that i need to include.
So the obvious clue that i was missing - which i could not for the life of me find - was a pinhole in the metal bracket which slots over a corresponding plastic pin on the main body. The metal bracket sits vertically - not horizontally - and actually provides the second contact point for battery number two, to close and complete the circuit. I’ve added further photography below to try and illustrate how it is seated within the casing:
I’ve uploaded three short videos highlighting the inner space between switch and motor as well as the layout of the top cover in the hopes that this might reveal the proposed location of the metal bracket:
thanks for uploading photos Stripey, really detailed, excellent photography skills. :) now i know what you were talking about. this metal part connects battery to the switch , as the switch slides up and down, it actually connects from this metal plate to the motor, its common in little dc devices to use a motor casing ( the chassis) to act as one of the terminals. i can see that the battery negative terminal has a spring and blue wire connecting to one of the motor terminals, but the second battery positive terminal doesn’t have anything to connect to, thats where the metal part comes in using one of the right angle surfaces to act as a terminal for the battery, whilst the other part extends to connects to the sliding switch. what i don’t see is some little narrow slot next to the battery, where the part would sit securely making its way through the plastic to the switch. maybe it’s in the underside of the other cover ? have a look, and good luck.
