I like tables and I like data. It’s just the way I am. So with that brief preamble I wandered into the NMRA’s Standards and Recommended Practices on their website (nmra.org) and, in particular, their one for track standards (S3.6). Since I have a pretty decent of inventory of rail and ties, in a variety of scales (your guess is as good as mine as to how that happened…) I figured I might indulge in building a turnout, maybe in Sn3 or S scale, standard gauge. Before embarking on that, I figured it would be handy to invest in some gauges or at least familiarize myself with what the standards might be for S.
What surprised me was that, in what the NMRA refer to as “Standard Scales” the standards defining turnout dimensions are identical between HO and S so, in theory, I could use the NMRA HO track gauge I already have on hand during the construction of an S scale, standard gauge, turnout. Here are some example dimensions from S3.6 as examples (units are millimeters):
|Scale||Scale Ratio||Gauge||Points||Point Clearance||Flangeway|
Obviously, the track gauge is different between the scales but the dimensions around the flangeways are the same. I thought I’d check these using their S3.6 for 4.2 wheel standards. The tread that they recommend is the same code 110 tread. The HO scale flange depth is recommended to be 0.028″ where in S they call for 0.030″. In theory, if could apply this to the idea of simply re-gauging HO scale and gauge wheels to S if you really wanted to get carried away.
While here anyway, I whipped out my calculator only to find that those bricks I was making in 1/35 wouldn’t be unreasonably small in S either. Just something to think about right now and maybe later on too.