With what Bill wrote (see below) in mind, here is an excerpt from a recent conversation I had with Ed McCamey about a recent change at the NASG and/or NMRA concerning this matter. How does this affect what Bill wrote below (if at all)? :
>> You would essentially use the old RP3 and RP4 specifications (now in >> the S3.1 and S4.1 as fine options) with adjusting for the check gauges >> to fit the S gauge. The NASG has recently dropped the older use of >> code 88 for the "Proto" use and adopted the NMRA code 87 for Proto:64. >> I'd recommend you use standard S scale check gauge - but construct >> turnout flangeways in the frog to 0.042" maximum. John Degnan [email protected] ----- Original Message ----- From: Bill Nielsen To: [email protected] Sent: Monday, August 08, 2011 07:08 PM Subject: {S-Scale List} Re: NEW PRODUCT : Code 88 Wheel Sets!!! The NASG/NMRA track & wheel dimensions were developed to work together as a set for optimal operation. These dimensions also allowed for some tolerance (usually only a few thousandths of an inch) to provide some room for construction variations. The original wheel tread width dimension is a critical one that allows the wheel to cross over the gaps at the frog without dropping, and also will require that the track gauge be more accurate. Theoretically, if your track and turnouts are made to current NASG standards, optimal operation will be with the use of NASG wheel profiles, and operation with code 88 wheels will be less reliable. In other words, for optimal operation, if you change the wheel tread dimension, you should also change some of the track/frog dimensions too. This also means that ALL of your wheels need to have the same profile (locos included), whichever dimension you decide upon. Trying to run both sized wheels on the same track means that operation with one (or both) will be a compromise. The only commercial turnouts I have seen (in S or HO scales) that are truly NASG/NMRA are those built using Fast Tracks fixtures. Best of luck, Bill ------------------------------------ Yahoo! Groups Links [Non-text portions of this message have been removed] ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/S-Scale/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/S-Scale/join (Yahoo! ID required) <*> To change settings via email: [email protected] [email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
