An Introduction To P64

Welcome to the Proto:64 Special Interest Group's (SIG's) presence on the world wide web. This site should answer all of your questions about Proto:64 modeling, who's doing it, and why we would like you to join us. The original author of this site was Keith Thompson. If you have any questions about this site, please contact the Webmaster at:
tc2 AT dapenguin DOT net

What is Proto:64?

Proto:64 is S scale (3/16" = 1') modeling using finer standards for track work and wheelsets. The most obvious difference between Proto:64 standards and NMRA/NASG S "scale" standards are the width of the wheels and the associated narrower flangeways. The existing NMRA S-4 standards use wider-than prototype wheels to compensate for less-than-fastidious track work.


NMRA/NASG Code 110 "Fine Scale" Wheel Profile	NMRA/NASG Code 124 "Course Scale" Wheel Profile	NMRA P64 Code 87 proto Wheel Profile Compared to NMRA/NASG RP25 Code 110 "Fine Scale" and Code 88 " XFine Scale" Wheel Profiles		Prototype Wheel Profile

Why Proto 64 now?

S scale standards were developed years ago when machining and molding techniques weren't as sophisticated as they are today. The resulting model work is still quite good but Proto:64 practitioners are striving for that "just like the prototype" look. Proto:64 takes advantage of finer tooling techniques and better materials. Don't get us wrong, we all come from the S scale world and some of us pick and choose Proto:64 standards to suit our own individual tastes. The glue that binds us is a desire to have the most realistic models in 3/16" scale.

To view the current data an the NASG standards page:
NASG Standards Page

To view the data an the our local standards page:
Standards Page

To join in our discussions please join our eMail list, Proto64 on Groups IO:
Join eMail List

This Page Updated February 23, 2024