Large Scale Central

The proposed NMRA standards for LS

Track and Trestles
#1

Hi all,

OK, this links to the PDF with the proposed changes for the scale designations.

OK, this links to the PDF with the proposed changes for the track gauge dimensions. The 1.768" is 44.9mm in metric with a +/- tolerance of .002" (.05mm).

OK, this links to the PDF with the proposed changes for the track gauge dimensions of the Hi-Rail stuff. Apparently for garden railroaders.

Since this is “out for comment” will any of you comment to the NMRA? Or just let the NMRA be the NMRA?

I just marvel at the proposed tolerances and I have a really good chuckle when I compare the proposed with what is actually out there. Did these guys do some sampling? Sure doesn’t look like it to me!

#2

This should bring a hoot from some of the Brits etc. My dear friend Terry roasted me well done for suggesting that 16mm (1:19) was a niche scale. I notice that the NMRA doesn’t even acknowledge it’s existence…nor does it acknowledge he existence of 7/8ths which I model in. I also didn’t see Gn15. When setting standards…and especially if they are revising old ones (especially track) I agree with others that it would be much simpler and more understandable if it were metric. I just wish the NMRA would stick to HO, O and the other dinky scales and stay out of G & F scales…and the other niche and ride-on scales.

#3
Hans-Joerg Mueller said:
I just marvel at the proposed tolerances and I have a really good chuckle when I compare the proposed with what is actually out there. Did these guys do some sampling? Sure doesn't look like it to me!
Why are you criticising the NMRA for advocating exactly what you have been advocating: tighter tolerances for track? Your own measurements have shown that so-called G-scale commercial track is all over the place in terms of tolerances. Just because the manufacturers are sloppy doesn't mean the NMRA should advocate or tolerate sloppiness.

As an aside, it’s interesting to note that they have a different dimension for Nn3 than they do for Z.

#4
Warren Mumpower said:
This should bring a hoot from some of the Brits etc. My dear friend Terry roasted me well done for suggesting that 16mm (1:19) was a niche scale. I notice that the NMRA doesn't even acknowledge it's existence....nor does it acknowledge he existence of 7/8ths which I model in. I also didn't see Gn15. When setting standards..and especially if they are revising old ones (especially track) I agree with others that it would be much simpler and more understandable if it were metric. I just wish the NMRA would stick to HO, O and the other dinky scales and stay out of G & F scales...and the other niche and ride-on scales.
I can't help but think that the G-scale world is at the same stage today as HO was around the mid-20th century: a tangled mess of pseudo scales and non-compatability. How many knuckle couplers are there, and what exactly is the scale of the Genesis?

The NMRA did good service to sort out that mess with the smaller scales and maybe they can help us as well. At worst, it’s unlikely they’ll hurt us.

I agree with you though that they seem blissfully unaware of “that other planet” (ie. the non-USA). On the other hand, I’m not sure it would be wise to tackle the Gn15 world. Its charm is in its eccentricity.

#5
Kevin said:
Its charm is in its eccentricity.
Kind of like this board....:D

From the stand point of the US, that would also hold true for 7/8ths and 16mm. I don’t see the NMRA accomplishing anything. With LS it’s going to have to be the manufacturers. Until we can lock the CEO’s of several manufacturers in a room and say you can’t come out until it’s settled we will continue to have sloppy track, incompatible couplers and a world of different scales.

I don’t see any manufacturers congregating any time in my lifetime. Unfortunately the manufacturers we need to get together are all on their own ego inflated proprietary trips.

#6
Kevin Morris said:
Hans-Joerg Mueller said:
I just marvel at the proposed tolerances and I have a really good chuckle when I compare the proposed with what is actually out there. Did these guys do some sampling? Sure doesn't look like it to me!
Why are you criticising the NMRA for advocating exactly what you have been advocating: tighter tolerances for track? Your own measurements have shown that so-called G-scale commercial track is all over the place in terms of tolerances. Just because the manufacturers are sloppy doesn't mean the NMRA should advocate or tolerate sloppiness.

As an aside, it’s interesting to note that they have a different dimension for Nn3 than they do for Z.


Very simple: +/- .002" (.05mm) is, in my opinion, not realistic. A tolerance that remains the same (+/- .002") from Z to LS?

Strictly an observation on the methodology. :wink: :slight_smile: But I have seen plenty of instances of similar “precision tolerances” in NA industry emanating from “offices”, no surprise there!

#7
Hans-Joerg Mueller said:
Very simple: +/- .002" (.05mm) is, in my opinion, not realistic. A tolerance that remains the same (+/- .002") from Z to LS?

Strictly an observation on the methodology. :wink: :slight_smile: But I have seen plenty of instances of similar “precision tolerances” in NA industry emanating from “offices”, no surprise there!


True. Judging by your measurements, even getting within 1mm would be a big improvement in track gauge.

When looking at the NMRA numbers, I tended to think of it as a tight tolerance for large scale and progressively more lax toward the smaller scales. I suspect you’ve interpretted it in the opposite direction.

I also agree that it would be difficult to achieve these toleranes, and it seems pointless to have tolerances that are not practically achieveable. A new manufacturer would look at the numbers and conclude that it’s not even worth striving to meet those standards.

Despite the practicality or otherwise of the proposed standards, I welcome the NMRA’s input. It’s not like they’re going to burn down any factory that doesn’t meet their tolerances.

#8

Kevin,

I haven’t done the interference checking yet, but whenever one does the +/- method from a nominal dimension, one runs the risk of running into either overlap (interference) or huge gaps on the other extreme.

As I mentioned before, internal dimensions going from “Nominal” to a “+” tolerance and external going from “Nominal” to “-” tolerance pretty well preclude those problems. DIN, ISO and VSM come to mind.

It get’s even more interesting when one uses the “+/-” method in a certain manner like the track gauge/back-to-back for wheels. If I have the time I’ll have a closer, detailed look at the actual proposed dimensions.

It’s the age old story: Will it fit and function when one assembles it?!!?

#9

NMRA cant do beans without mfrs support, and the mfrs are quite content in there belief that their proprietary way of doing it is correct, so unless the consumers can convert the manufacturers, forget ever having a standard coupler or uniform standards other than Kadee knuckles or Ozark link and pins.

I dont even want to go into proprietary control systems like Marklin, LGB MTS et al.

#10

Hans-Joerg,

Comments are for members of the NMRA, same as voting on the standards… Any way that’s what I was told when I joined back about 1995… Dropped out after they sat on there hands for 6 years & did nothing…

Vic,

You are right, the owners are gona have to adopt the standards… If they do not, then it is “SNAFU”…

#11

I have to feel the NMRA has become as unimportant as the “Red Box Brigade”. It means nothing to my enjoyment of the hobby and less to my allocation of funds to the hobby. I also gave the NMRA some of my funds for years and found it was nothing but a bunch of old farts wanting to support their own hobby by establishing “Life Memberships” and then jacking the annual dues to unrealistic amounts and hoping anyone not a “life member” would continue to help support their enjoyment until the “life member” died. T’aint going to happen.

No offense meant to anyone that wants to be an NMRA member, but check the finances. Its unrealistic.

#12
Ric Golding said:
I have to feel the NMRA has become as unimportant as the "Red Box Brigade". It means nothing to my enjoyment of the hobby and less to my allocation of funds to the hobby. I also gave the NMRA some of my funds for years and found it was nothing but a bunch of old farts wanting to support their own hobby by establishing "Life Memberships" and then jacking the annual dues to unrealistic amounts and hoping anyone not a "life member" would continue to help support their enjoyment until the "life member" died. T'aint going to happen.

No offense meant to anyone that wants to be an NMRA member, but check the finances. Its unrealistic.


Ric,

I was a member for 10 years because our round-robin club stipulated it, left that club, and the NMRA not long after, in 1986.
Oh yes, we had quite a few “Life Members” :wink: :).

As far as the NMRA LS Standards are concerned; interesting reading, but nothing that would make me change from the NEM Standards. I prefer Standards to be logical and straight forward. :wink: :slight_smile:

#13

Personally, the trouble with the NMRA and large scale is that from the beginning the NMRA always treated large scale with an almost derisive attitude like a troublesome orphan that no one wanted.

Even given LGBs unapproachability to adopting any US based standards they could have started trying to make inroads in the early days of LS, but they viewed garden railroads as “not serious” model railroading and scoffed at the idea of treated the new scale the same as HO or N.

#14

Vic,

Did you not know that we play with toy trains!! Even with all the scale stuff out there they still look down there noses @ us… I think they are jealous of us because we have to do it like the real RR’s in the dirt, wind, rain & snow …