Instructions to build a ball run using the Grimms Rainbow, Basic building set, stepped roofs, bridges and semi-circles. This one is optimized for the small-balls.
grimms marble run
When you’re setting up to build a Ball run using blocks, the size ball you pick makes a big difference. If you’re playing with a very small child, then you need a ball that is not a choking hazard. If you’re working with a young builder, you need something that won’t be frustratingly heavy or light.
Step-by-step instructions to build a self-propelling Grimms Spiral Ball Run