- Location
- Worcestershire
I'll try to remember and take photos next time I'm near it, basically a wiper motor with a short arm on it which pushes open a spring trap door. Spring closes it. There is another slide above it which is adjusted with thumb screws to adjust the trap door size
One we have is as above using a half pipe rotating with a lever and length of rope and leaving a kg (I think).
Rob Astley flavour.