What size of wheel flanges will run best on peco code 75
Any wheels that is of RP 25 or NEM standards.
Is there a reason for the Peco code 75? Is this what you plan to use or existing? Am not exactly sure, but I believe you have a larger choice of turnouts in 83. This is of course for production parts.
I do not believe there will be a problem running any equipment currently in production from the major vendors. NMRA RP-25 sort of rules the market today. Wheel flanges were an issue years ago with all the toy train type stuff Tyco, Marx, Lifelike, etc. and especially the AHM/Rivarossi 0.39 flanges. We called them pizza cutters. Unless you are buying old equipment or really cheap equipment (e.g. bottom of the line Model Power, Lifelike, Industrial Rail comes to mind) there should not be an issue.
Today I would think to look at the hooks. If the couplers are the old horn hook, then is the time to start worring about the wheel flanges.
My IHC steamers ran fine on the club’s hand laid code 83. IHC flanges are deeper than RP-25. From that, it is safe to say that RP25 flanges will work fine. The NMRA gauge will tell you if the locomotive in question has RP-25 flanges. US made equipment has been compliant with RP25 for many years. Only really old stuff will have deeper flanges.
Actually, the NMRA gauge measures compliance with the NMRA Standards, not Recommended Practice (RP) 25. The allowable flange depth is by the standard is 0.030 inches, not the 0.025" of RP25. There is plenty of train set equipment “made” by Model Power and others that is not RP25 compliant. Pilot wheels on steam engines are a frequent offender, often exceeding the NMRA flange depth.
That said, with code 83 rail it doesn’t matter except for the very deepest flanges on European-made models (think old Rivarossi and AHM and possibly older IHC). The differences in NMRA flanges I have listed become important when one starts using code 55 and code 40 rail. Code 70 rail runs any NMRA-compliant flanges, but generally not the NEM (European) pizza cutters.
my thoughts, your choices
Fred W