I purchased the wheels, ready turned, from Roanoke. Next time, I will do them myself, but I wanted to complete this locomotive quickly, so took the easy way out. Having said that, they came as simple disc wheels, and, after looking at them for a few days, I decided that I'd rather they had a dish cut out (to look like 'proper' wheels). Thus, I spent a couple of hours on the lathe at the SNBR removing a large quantity of steel from them.
Next came the axles. These are fairly simple affairs, turned from 1.25" bar (13" long from Maidstone Engineering Services). Then, they had keyways cut in them for the sprockets. The first time I'd used a milling machine in 20 years..
Then the day of reckoning came - assembling the wheels on to the axles. I had made the axles so that they were a relatively tight fit into the wheels, and loctited them as well (I used loctite 601. I have heard 638 recommended, but the minimum quantity of that sold was enough to keep me going for the rest of my life. The supplier also told me that 601 was nearly as strong, and comes in smaller containers). I fixed one wheel, then added the sprockets, then, a day later, added the second wheel. A business trip abroad meant that the lot got a week to cure.
On my return to the UK, I put the chassis on its wheels. I put the bearings on the end of the axles, then turned the chassis over to put the axleboxes into their slots. Then, I added the spring keeps. When I turned it back over, there she was at last - on her wheels
The connecting chain between the axles was added next. Then, I made the layshaft. This is a short length of 1" diameter bar, with keyways cut into it for the sprockets. The layshaft brackets were then bolted up, and the whole lot assembled on to the frames. The connecting chain to the axles was added next.
The frames, on their wheels at last. Layshaft also assembled, and work is well underway constructing the transmission bracket (the big plate with the circular hole in it). Note also the rear axle end covers - essential as the driver's feet will sit on the step just here.