Bob, it about time you read the information on my web page and Railway Engineering's web page about H0 fine scale. You DO NOT need to change the wheels on most regular US 'crude' HO standard rolling stock. The correct gauge for standard rolling stock uses scale clearances, not sloppy NMRA clearances. The correct minimum gauge is caculated on XL spread sheet on my web page. Performance is what counts, and using sloppy NMRA clearances results in increased chance of derailment.
Terry Flynn
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HO wagon weight and locomotive tractive effort estimates
Which fine scale standards are you talking about??? Steve's changes to the NMRA standards is to fix the gauge problem with the track. I'd not call that fine scale. All of the real fine scale "standards" have refined the wheel contour as well as change the track dimensions and this isn't where you really want to go if you run regular equipemnt without any changes in the wheel contours. Please understand that there is a difference between running RP-25 wheelsets and fine scale wheels. I hope that we don't have to have this discussion again. It hasn't been the first time for this in variuos forms and it's a bit tiring to have to keep identifying the difference between proper track dimensions (I fought a big battle with the NMRA engineering dept. back in the early '80s) and what the various "fine scale standards" are. The end result of the argument that I had with the NMRA was to have the track gauge decreased by one thousandth of an inch, hardly what I was promoting.
-- Why do penguins walk so far to get to their nesting grounds?
The answer to your first question is the H0 fine scale standard as defined on my web page. You may not call Steve Hatches track standard fine scale, but that is what it is. He also makes Proto 87 track. The NMRA calls H0 track with flange ways of around 1mm wide fine scale and that is what it is. Proto 87 is the name of the standard that uses close to exact scale dimensions. NMRA RP25 does cover fine scale H0 wheels, however this RP has always produced hard to make poor tracking wheels compared to correctly designed alternatives. See my web page for an easier to make superior H0 wheel profile. H0 fine scale wheels use flanges about double scale size. That reality has been around since the first fine scale H0 layouts were built before the existence of the NMRA. The current NMRA H0 S3.2 standard and the NMRA S3.1which includes NMRA fine scale and NMRA Proto 87 are all using a flawed formula which results in hard to make track. I suspect the formula is scaling down some of the prototype dimensions. The reality is you cannot scale down all the prototypes manufacturing tolerances. That's why the NMRA's Proto 87 standard is impractical. The NMRA fine scale standard is a waste of time because you need to replace or reguage all your wheels and still end up with an over wide wheel front to front dimension. The NMRA standard S3 track has the same tight span to back to back clearance as the fine scale track I use, making the NMRA standard with it's coarse flange ways unsuitable for track using 18" radius curves for most US prototypes. Another reason manufacturers making train set's ignore the NMRA S3.2 standard. Those in control of the NMRA standards committees have shown they do not understand how to design properly toleranced practical standards with relevance to ready to run equipment. Even with existing standards (Proto 87), they change things for the worse.
Terry Flynn
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HO wagon weight and locomotive tractive effort estimates
You're not listening to what I said. I never called Steve's track standard a fine scale standard. I've not been to see what he's been making for a long time but I've known him for a long time and was around while he developed the narrower gauge for HO standard gauge. I know why he did it and have seen the results of both his work and my own work on trackwork. I'm not interested in fine scale trackwork as that trackwork won't accept equipment from others unless it has been modified to meet that standard. Besides, I consider detail above a certain level as unnecessary. It's nice to have scale width wheels with scale flanges but then you go and blow it with unprototypical couplers and other such things. Even the springs in the trucks done't scale well.
-- Why do penguins walk so far to get to their nesting grounds?
Clearly you are having trouble translating my Aussie English into North American English.
I was the one who stated Steve Hatches track standard is a H0 fine scale standard and my H0 fine scale standard is my metric version developed from Steve's unpublished? standard. All I have done is provide a metric version of it after doing the sums to prove to myself his solution was valid. Therefore what you use and I use is the same, within 0.05mm. I call it H0 fine scale because that is what it is. It does not comply with any H0 NMRA standard. The NMRA H0 fine scale standard is different and incompatible with ready to run equipment. The NMRA should discard it's H0 fine scale standard. Proto 87 is not H0 fine scale, it's a close to exact scale standard and should always be referred to as Proto 87. The NMRA has it own version of Proto 87 which is different but just as problematic as the original standard developed back in the 1970's. I to share improved running thanks to Steve's work in this area and don't have to change wheels or work to unrealistic tolerances. I also agree with you about the level of detail above a certain level being unnecessary. So the only difference of opinion is about terminology of what is H0 fine scale and what is not H0 fine scale.
Terry Flynn
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HO wagon weight and locomotive tractive effort estimates
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