Ken, and others, Be advised that if you go with G1MRA 1F wheel profile the trackwork will need to be of fine standard as well. This is particularly important if there is any intention of selling them in the modeling market. It might be worth building in a bit of extra material on the backside for those using non-1F standards allowing them to machine a wider tread.
A wheel, if based on 1F standards, requires that turnout guardrails are set at 1.75 mm vs 3.0 mm on the non-fine standards. The narrower the tread the more of the wheel drops at the half point of the frog. The 1F standard also has is less wheelset to track gauge side "slop", this being .75 mm total for 1F and 2 mm total for non 1F standard. Gary Broeder
