Is it a roller coaster? A marble waterfall? Whatever you call it, it's a blast to build and just as much fun to operate. When we're at a show, we find we have to "test" our display model every time we walk by.
Turn the crank and the marbles are carried to the top of a ramp by a giant gear. From there, a series of steps moves them even further up, until they are deposited at the top of a long whirlpool ramp, there to drop back down and do it all over again.
Finished model is 10" wide x 9" deep x 8" high. Kit comes with 238 laser-cut plywood pieces, steel marbles, bushings, axles, and all other parts needed for assembly. Recommended for ages 14 & up.
Notes from Alex:
This is one of my personal favorites out of all the wood kits we sell, and we finally got around to assembling our sample. They've made some substantial changes to the design of the kit which make it MUCH easier to assemble.
Build time is 7-8 hours, but that would not include the time needed to make sure that any glued sub-assemblies are dry. This is definitely not something that can be done in an evening.
The only major piece of advice I'll offer is to make sure the cams that operate the steps on the left side be extremely well-waxed. We spent some time operating the sub-assembly by hand before adding it to the base, to make sure nothing would hang up.
We'd also recommend putting silicone or rubber feet on the bottom of the model to keep it from sliding while in operation.