I bought a pneumatic spark plug cleaner via eBay recently but initially not impressed with its performance.
It seems quite a popular item on eBay as there are a lot of sellers of the same product – which was one of the main reasons I bought it.
After some experimentation i managed to get it working ok. There was insufficient grit supplied with it which meant it wasn’t sitting high enough inn the trough to be sucked into the air flow so I put a few large nuts in the bottom to fill the space and rise the grit level. I also mounted it on a block of wood so I could tilt it a little.
In the end I got some good results but not sure I would recommend it to others.