One of the things I love about sharing my modelling progress is the opportunity to learn from my friends. At the North Shore Model Railroaders virtual meeting this Wednesday, I shared the pitiful progress I’ve made on Percy in the last two months, culminating in the photo of the half-assembled gearbox. I commented that I though the mesh of the worm and gear looked a little tight, and that is when I learned about the paper test. Ideally a piece of cigarette paper should fit between two gears. So I had to try it with the latest incarnation of the gearbox; it appears to be fine.
Pembroke:87 
Hi Rene,
So there were gears in your presentation. I liked that paper tip too-the cigarette paper making perfect sense. Makes the virtual meets feel worthwhile.
Cheers,
Graham