7 ¼ verses 7 ½ How did this happen?

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Cary Stewart
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Joined: Wed Jun 08, 2011 5:54 pm

Re: 7 ¼ verses 7 ½ How did this happen?

Post by Cary Stewart » Thu May 16, 2013 10:45 pm

Hello All,
I am very late getting into this thread but here goes.
First off. If in the US or Canada check the local clubs where you live and build to the gage that they are using.
New Jersey and Long Island + the full North East of US and Canada are 7 1/4".
Everything west of there is 7 1/2" unless an individual does different.
The whole problem started with a mistake in a small article in a newspaper. I once was shown a copy of that article and read it. It left me totally confused and I understook how the error occured. Who wrote the article? I was told that it was Mr. Little Engines him self. No confirmation on that. What a mess it caused. Walt's track was an anomally in So. Cal. but it was closer to scale and that is what he wanted.
Cary

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Rich_Carlstedt
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Location: Green Bay Wisconsin USA

Re: 7 ¼ verses 7 ½ How did this happen?

Post by Rich_Carlstedt » Sun May 26, 2013 8:55 pm

The problem is not the gauge of the tracks, but the scale of the locomotive ?
"NO" track gauge is scale !
3 1/2 should be 3 17 /32 "
7 1/4 and 7 1/2 should be 7 1/16"
What we have are trains that are close to scale and "adjusted" to fit tracks.
This is why the move to a 1.6" scale construction has appeared.
I think Dave's lament was the lack of "standards" and not track gauge itself.
The back to back rules do not coincide with the gauges as he pointed out.

So as we move forward, with the aid of computers and CAD, it becomes a simple proposition
to create a loco at 1.59 scale, or whatever melts your heart
Rich

By the way,
I do know one purist who built his Locos, trains and track at 1.5" scale.
He runs them on his 7 1/16" gauge track.
It is a magnificent layout
Last edited by Rich_Carlstedt on Mon May 27, 2013 8:33 am, edited 1 time in total.

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Harlock
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Re: 7 ¼ verses 7 ½ How did this happen?

Post by Harlock » Sun May 26, 2013 11:05 pm

I think the best thing to do at this point if you want to be a scale purist is to build to the right scale for the tracks you want to run at. The tracks and all the legacy equipment aren't going to change. Much easier to fix your own stuff as you build it. Your back to back dimension is the starting point.

Also, 2.5" scale is exact for 7.5" gauge for 3ft prototype, and 3" scale for 30" gauge prototype, so for all of us narrow gauge modelers out West, our odd-ball 7.5" gauge suits us just fine, except for the fact that we are running on ~1.5" scale flanges and wheel profiles on these larger engines.

Also, as far as I'm concerned the source of the 7.25" / 7.5" divergence is still an urban legend until someone actually comes up with the documents in question, whether it's a miss-typed fraction symbol in a letter from an IBLS secretary or a purported magazine article, etc.

-Mike
San Lorezo Flume & Lumber Co. #2 - "Felton"
Live Steam Photography and more - www.mikemassee.com
Contributing Editor, Live Steam Magazine
Webmaster, Allen Models of Nevada

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LVRR2095
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Location: Maine, USA

Re: 7 ¼ verses 7 ½ How did this happen?

Post by LVRR2095 » Mon May 27, 2013 7:03 am

Rich_Carlstedt wrote:The problem is not the gauge of the tracks, but the scale of the locomotive ?
"NO" track gauge is scale !
3 1/2 should be 3 17 /32 "
Rich
Rich, the clubs here in the Northeast do gauge their 3/4" scale tracks at 3 - 17/32" gauge.

Keith

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Rich_Carlstedt
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Location: Green Bay Wisconsin USA

Re: 7 ¼ verses 7 ½ How did this happen?

Post by Rich_Carlstedt » Mon May 27, 2013 8:33 am

Thanks Keith...didn't know that .
My hats off to you fellows

Rich

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rkepler
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Re: 7 ¼ verses 7 ½ How did this happen?

Post by rkepler » Thu May 30, 2013 9:07 pm

There is at least one track with a very good reputation that is built to handle 7 1/4 as well as 7 1/2 gauge - the Wimberley, Blanco and Southern. As I understand it the track is gauged close to 7 1/2 but far enough below that 7 1/4 gear runs. My 7 1/2 gear sang a little bit but ran just fine with no derailments. Not really sure what they did with the frogs, next time I'm there I'll have a look.

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LVRR2095
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Location: Maine, USA

Re: 7 ¼ verses 7 ½ How did this happen?

Post by LVRR2095 » Fri May 31, 2013 5:10 am

There is more than one track that handles both gauges.
I know of one here in Maine, another in Nashua, New Hampshire and the Cincinnati club in Ohio also handles both.

Keith

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Highiron
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Location: Lancaster, PA

Re: 7 ¼ verses 7 ½ How did this happen?

Post by Highiron » Fri May 31, 2013 5:48 am

rkepler wrote:There is at least one track with a very good reputation that is built to handle 7 1/4 as well as 7 1/2 gauge - the Wimberley, Blanco and Southern. As I understand it the track is gauged close to 7 1/2 but far enough below that 7 1/4 gear runs. My 7 1/2 gear sang a little bit but ran just fine with no derailments. Not really sure what they did with the frogs, next time I'm there I'll have a look.

Nicks track is built to very strict gauge, they machine or cast a 1/2" or slightly larger groove in the flange way of the frog and set the gaurd rails at standard so as to have the correct BTB for 7 1/4" gauge..I did the same thing when I had the track in Jackson, NJ..gauge was set at 7 1/2 for tangent and 7 9/16 for curves

Mike

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