Oh, if only those lovely Banner and Kraft Wheels were still being made ! I am completing a scratch built Oriental and am using Williams Brothers 2-1/4" Diameter Smooth Contour Wheels(P/N 14000), for the main wheels. The Williams Brothers instructions show using a wheel collar placed over the axle, under the snap on cover, however there is not enough room for a standard wheel collar, in the limited space under the snap on cover . One of our C/L Club members is an excellent machinist and he used his lathe to thin down some standard wheel collars enough so that I was able to use the thinner wheel collars and to cover over the axle ends when the snap on covers are in place. I cut an Allen Key end down enough to be able to get into the limited opened hub space and tighten the now thinned collars' set screws, before snapping the covers in place. Does anyone have any other suggestions for how use the covered over Smooth Contour Wheels, other than soldering on a permanent retention washer? I really like the clean appearance of those Smooth Contour Wheels.

I use solder washers but like Dennis' idea and will try it the next time I install this type of wheel.  The washers are not permanent, a touch of the iron and they come right off. 

My buddy Pat retain his wheels with a spring clip he makes. Works pretty well.

He has a jig he uses to twist the wire into sort of springs with a tab to back it off.

Where do you buy the Williams bros 2 1/4 Smooth contour wheels nowadays. I used them many years ago and found them very nice, just a bit heavy. But anyway better on tarmac than foam rubber wheels. L