Jim:- The gears used on the Climax are not spiral bevels, but skew bevels. As I understand it a spiral bevel, as usually sold, is similar to the well known straight bevel where the shafts meet at a point, but has spirally cut teeth to give a greater contact area and greater smoothness.
A skew bevel is used where the shafts have to cross each other. The "skew" gears you describe from Muffetts sound like what I've always called helical gears and do exactly what you say they do. Although they could be used on a model Climax (4 pairs of one hand and one of the other to give the correct crankshaft rotation) they would not be a correct representation of the gears on the full sized loco. (Neither would Kozo's, if you want to be pedantic about it, but they're close.) A helical gearset is identical, as far as I can see, to a very low ratio worm and wheel. It was used in the '30s on the geared Avonside locos (a British interpretation of the Heisler design), where, as I recall, the ratio was about 1:2 and makers actually referred to it as a worm gear. I'm admit that I'm open to correction - I'm no expert, just trying to find a path through the maze. Mike
