7 ¼ verses 7 ½ How did this happen?

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Trainman4602
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7 ¼ verses 7 ½ How did this happen?

Post by Trainman4602 » Mon Jun 16, 2008 7:06 pm

There have been a lot of stories about the reason for the gage difference in the United States, This is what I heard.

First off 7 ¼ gauge is the world standard. In the UK, Europe. Australia and the rest of the world the excepted gauge is 7 ¼. You will only find 7 ½ gauge it the USA.

The story goes like this.

In the early fifties Lester Friend (Friends Models) built a Boston and Albany Hudson. It was 1 ½ inch scale and built to 7 ¼ inch gage. The excepted standard for 1 ½ in scale. He got this specifications form Carl Purinton, the founder of the Brotherhood of Live Steamers. Carl explained that in the UK that was the standard for 1 ½ in scale.

Why 7 ¼ I have no clue. The gauge scaled down should be 7 1/16. In any event the gauge was to be 7 ¼. Some time later Seymour Johnson approached Little Engines founder Martin Lewis. Seymour wanted to build a 1 ½ 4-8-4. Mr. Lewis knew that Lester Friend had a 1 ½ locomotive so he wrote to him asking for specifications.

What I heard was that when Mr. Friend answered the letter he “typed” it. Back in the day some typewriters had the ¼ and ½ key on the same key. One needed to use the shift key to type either fraction. I heard it was a typographical error that caused this difference.

One other theory is that Seymour had a 15 inch gauge railroad with quarter scale equipment. Quarter scale is 2X size to 1 ½ in scale. They simply divided it by 2 and came to 7 ½ in gauge. Some time had passed Seymour had the locomotive and I believe the track also had been built so he wasn’t going to change it. Little engines , being one of the only suppliers, with a heavy add campaign advertising in Popular Mechanics and other national magazines promoted 7 ½ gauge. From there it grew.


To further and to the gauge problem

As mentioned Carl founded the IBLS. When Bill Fitt expanded the Live Steam News Letter in the late sixties he added the names of the IBLS secretaries. This helped new interested builders to find a Live Steamer in their area to share ideas with. A great thing.

I’m not sure why but Mr. Fitt decided to publish the so called IBLS Wheel standards.

This standard was developed by the Los Angeles Live Steamers. It was printed in the back pages of the Little Engines Catalog and later in the Railroad Supply Catalog as well.

The standard gave specifications for the wheel profile and gauge for all gauges including 1 inch and ¾ scales. Now this is were the fun really begins.

The 1 in and ¾ in standards are fine. But the 1 ½ inch is another story. The wheel profile is not according to the international standard and the back to back is wrong as well. The back to back for 7 ½ is 7 1/8 . This is fine for that gauge. For the 7 ¼ gauge they just subtracted ¼ inch making it 6 7/8 inch The excepted back to back through out the world is 6 ¾ inch.

When I first got into the hobby in 1969 I started a LE 1 inch pacific. After attending my first meet at NJLS in 1974 I decided to stop that project and start a 1 ½ scale Locomotive. I asked some questions as to the specifications and was told the back to back should be 6 ¾ so I made my locomotive and cars to that standard.

The LALS, now the IBLS standard was published some time in the middle seventies. No one caught the error. It was just assumed that the LALS standard for 7 ¼ was correct.

Lone builders, started building cars and engines to the published spec.

Why wasn’t the eastern clubs contacted for their input? At that time the only clubs that had tracks here in the east for 1 ½ inch were PVLS and NJLS. PLS did not have a 7 ¼ track at that time.

So now we have two different standards for the original standard.

Here in the east there are some 6 ¾ BB cars and engines running. Some clubs here have modified the track to except both standards.

The 1361’s lead truck was built to the 6 ¾ BB std. Other engines that I have built were made the same. The deficit came into play at PVLS this weekend. As mentioned I haven’t been there in 25 years. I had no gauge problems years ago at PVLS.

The back to back dimension only comes in play at switch frogs.

After steaming up Dan and I headed out on the main line to test the equipment before hauling passengers. We negotiated all the switches up by the bays with out incident. After clearing the yards we came across a switch for the new valley division. This division was added a few years ago. The switches up by the bays and in the yards were set to except both BB standards. The new valley division switch was made to the new BB standard. That’s why we had a major derailment. The lead truck picked the frog. The switch is on a down grade so the heavy train pushed the locomotive between the two rails and stopped between the switch. All wheels on the ballast.

The club members and Dan helped to get her back on. Noting bent or broken.

I dropped the lead truck and with the help of Mark and one other guy and believe or not a sledge hammer pushed the wheels out 1/8 in. So much for precision work (CNC) LOL

The big question and I me BIG is why do we have a wheel standard but no track standard. Don’t they go together?

Let’s go a step further. How about car standards and some other safety issues.

With all the worry about law suites and so forth maybe now’s the time to do that.

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

Post by Harlock » Mon Jun 16, 2008 7:25 pm

Trainman4602 wrote:There have been a lot of stories about the reason for the gage difference in the United States, This is what I heard.
There's also another factor to consider - I think 7 1/2" gauge scales more correctly for 2 1/2" scaled 3 foot narrow gauge. (I did the math some months ago, have to find that scrap of paper)

So 7 1/4" gauge is most appropriate for 1 1/2" scale and 7 1/2" gauge is most appropriate for 2 1/2" scale, if you want to make the minimum amount of modifications from the prototype when scaling down.

I read with interest in some historical issues of "The Miniature Locomotive" from the mid-1950s some discussion regarding the gauge debate, which was brand new at the time.
Trainman4602 wrote:Let’s go a step further. How about car standards and some other safety issues.

With all the worry about law suites and so forth maybe now’s the time to do that.
Los Angeles Live Steamers, being located in a public park in a large city, has some pretty well defined car safety standards that they have developed over the years, with modifications and improvements being made continually based on what has worked and what hasn't. They probably have more to worry about concerning frivolous lawsuits and paranoid bereaucrats than any other club in the world.

Although they haven't put any specific documents online, a lot of the 'engine booster' magazines are there and enough digging may turn up some gems.

-Mike
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Dick_Morris
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Post by Dick_Morris » Mon Jun 16, 2008 8:37 pm

For what it's worth, I have a 1955 LE catalog. It lists the Northern, Atlantic, Pacific, American, and CP Huntington. All were 7-1/2 gauge. It was my impression that the Northern was the last developed of this group.

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Trainman4602
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Post by Trainman4602 » Mon Jun 16, 2008 8:56 pm

That maybe so. I’m not sure as to the time line. I do know that the LE American was originally a 6 ¾ gauge locomotive it looks a little short and wide. The Railroad supply American was a copy of Dick Bagley’s Disney locomotive.

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Post by JoeBlake. » Mon Jun 16, 2008 9:07 pm

It's not just with the bigger gauge. Don't you guys have 4 3/4 inch and everyone else being 5 inch gauge ?

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bcody
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7.5" TRACK GAUGE

Post by bcody » Mon Jun 16, 2008 9:27 pm

I'm not concerned with why there are two different gauges for the larger equipment. What I am concerned with is what is being done by the 7.25" gauge people to change their gauge to 7.5". It would open so many tracks for their use. Could it be because of the attitude I ran into while I was in the service and stationed on Cape Cod? If it didn't happen on the cape or at least in Mass they wern't interested. I ran into the same thing while stationed in Abilene, Texas. If it didn't happen in Abilene or at least Texas they wern't interested. I'm not concerned with the track gauge in the Northeast as I don't expect to ever be in New England again but it would open the tracks in the majority of this country to the people from New England. BTW - In looking at the track listings in LSRM I think about 90%+ of the tracks in the US are 7.5" gauge. Now you guys with the 7.25" equipment can yell and scream at me, its just my opinion. If you want to limit your running to less than 10% of the tracks in the US so be it. Bill

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LivingLegend
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Post by LivingLegend » Mon Jun 16, 2008 9:35 pm

Trainman4602 wrote:....The Railroad supply American was a copy of Dick Bagley’s Disney locomotive.
Actually, the Disney CP-173 is 7.25 gauge. There are also dimensions on the Disney drawings to build to 7.5 gauge.When design work started on Disney's loco (early 1950's), 7.25 gauge was chosen because it was the dominate track gauge for 1.5" scale

Also, if you look in the earlier Little Engines catalogs, you will find the printed chart of wheel and track gauge specs to be from the Southern California Live Steamers. SCLS was founded in the 1940's and preceeded LALS. Until shortly after Irene Lewis died, SCLS met at Little Engines, which was located in Irene's back yard.d.

If I remember correctly, the design work on the original LE 4-8-4 began in the late 1940's
Trainman4602 wrote:I do know that the LE American was originally a 6 ¾ gauge locomotive it looks a little short and wide.
Dave is correct about the LE 4-4-0 being desinged for a smaller gauge..... That is the reason it's so disporportonate in size to other 1.5" scale 4-4-0's of it's period.

LL
Last edited by LivingLegend on Tue Jun 17, 2008 2:05 am, edited 2 times in total.
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B&OBob
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7.25 versus 7.5 How did this happen?

Post by B&OBob » Mon Jun 16, 2008 9:40 pm

These days high quality locomotives for 5" gauge are built to 1-1/16" scale, which is the correct relationship. 3/4"-scale gauge is 3.531", not 3.50" as sometimes assumed.

Similarly, 17/32" scale (not 1/2") is correct for 2.5" gauge, where 56.5" prototype scales to 2.5013". Good enough for Government Work and at least one thing we can brag about in this scale!

Bob

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Post by ccvstmr » Mon Jun 16, 2008 10:00 pm

Before you start waving the "standards flag" again (as this was tried years ago and some of you might recall the problems with Mini-Rail insurance), I would suggest you go back and search the archives for info related to the LALS incidents and the "safety program" that was set forth. I was so close to writing a response to LALS, but family matters took precendent and I never got back to it.

Perhaps the more important part of generating standards is...what needs to be standardized? Answer that question first before trying to standardize everything. Only certain dimensions are critical...not ALL dimensions. And when it came to LALS, if I were any other club, I would take a major exception to having T riding cars that weighed (a reported) 300 pounds each...EMPTY! This is nothing more than rolling counterweight. Will that help LALS continue to operate? Probably, but at what cost? Okay, you say you can't put a cost on safety? Maybe not, but you might have second thoughts after replacing rail, wearing out locomotives, etc.

The unfortunate part of the entire affair is that you can't legislate idiocy! Common sense...is not so common and the general public is just not well tuned to riding such small scale trains. My suggestion at the time (and some might view this as a bit cynical)... because I didn't want LALS safety band aides to proliferate across this or any other country. If you have to haul passengers and provide a municipal service to the community...don't worry about 7.25 or 7.5 inch gauge issue. The BEST thing you could do for the hobby would be to push your wheels out to 12" gauge...or more. Because once the center of gravity falls outside the rail gauge (no matter what gauge you run on)...you going over.

Some readers may agree...some may not. But you can't argue with the legitimacy of wider wheel gauges result in a more stable riding platorm. Is this practical? I didn't say it was...I just said it was an alternative and perhaps a better alternative than jumping through other hoops. I think this is what they mean when the "laws of physics" are discussed. Then again, I never studied law in school. Just my 2 cents...fwiw. Carl B.

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Post by Doug_Edwards » Mon Jun 16, 2008 10:09 pm

LivingLegend wrote:
Trainman4602 wrote:....The Railroad supply American was a copy of Dick Bagley’s Disney locomotive.
Actually, the Disney CP-173 is 7.25 gauge. There are also dimensions on the Disney drawings to build to 7.5 gauge.When design work started on Disney's loco (early 1950's), 7.25 gauge was chosen because it was the dominate track gauge for 1.5" scale


LL
LL,

Didn't Walt Disney have his Bassett and Lowke 7.25" gauge engines before he started on the 173? Dave Rose also had a B-L engine, and I beleive his track was 7.25 as well.

It is a pity that Bassett and Lowke didn't get the gauge right to begin with, instead of the off gauge of 7.25.

Doug.
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Post by Doug_Edwards » Mon Jun 16, 2008 10:18 pm

ccvstmr wrote:
If you have to haul passengers and provide a municipal service to the community...don't worry about 7.25 or 7.5 inch gauge issue. The BEST thing you could do for the hobby would be to push your wheels out to 12" gauge...or more. Because once the center of gravity falls outside the rail gauge (no matter what gauge you run on)...you going over.

Carl B.
For clubs that have to haul the public, I agree with this. Lay a 3rd rail, and you could still pull the 12" gauge cars with 7.5" gauge locos. If you made the track 11.77" gauge, the gauge would be spot on for 2.5" scale standard gauge.

Doug
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Building a 70 ton Willamette in 1.6"
Building a 80 ton Climax in 1.6"

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Post by Harlock » Mon Jun 16, 2008 11:44 pm

Doug_Edwards wrote:
ccvstmr wrote:
If you have to haul passengers and provide a municipal service to the community...don't worry about 7.25 or 7.5 inch gauge issue. The BEST thing you could do for the hobby would be to push your wheels out to 12" gauge...or more. Because once the center of gravity falls outside the rail gauge (no matter what gauge you run on)...you going over.

Carl B.
For clubs that have to haul the public, I agree with this. Lay a 3rd rail, and you could still pull the 12" gauge cars with 7.5" gauge locos. If you made the track 11.77" gauge, the gauge would be spot on for 2.5" scale standard gauge.

Doug
I agree that 7.x gauge is a very poor choice for hauling the public. We're starting a museum locally and I won't put anything in smaller than 12" for public hauling. But occasional rides on 7.5" to get people interested is a very good thing... :) not revenue service though. We plan to have both for different purposes.

--M
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Contributing Editor, Live Steam Magazine
Webmaster, Allen Models of Nevada

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