# Lgb 1200 series switches



## John J (Dec 29, 2007)

Does anyone know what the R rating of the LGB 1200 series switch is?

Do you know how it equates to a 4 ' . 8'. 10' or 12'? 

JJ


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## chuck n (Jan 2, 2008)

JJ, it is 4' diameter. It matches the 11000 series curves in length and angle (30 degrees)

Chuck


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## Garratt (Sep 15, 2012)

Actually I think it is metric so not 4ft but 1200mm diameter. There is about a 19mm ( 3/4") difference.
So it is closer to 47.244 inches diameter.

Just as well it is not rocket science, otherwise you guys would miss the moon.

Andrew


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## chuck n (Jan 2, 2008)

I've never done the calculation. If LGB says that it is 4', that is close enough. With the flex in the joiners I'd love to see an exact 11000 circle.

I believe that the measurement is from the center of the track. The outside rail will exceed 48 inches and the inside rail will be less. BFD.

Chuck

PS This has nothing to do with the original question.

PPS Laying track isn't rocket science. It is a little like hand grenades. Close is usually fine.


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## Garratt (Sep 15, 2012)

LGB don't say it is 4'. They use metric in Germany. It is 1200mm diameter.
Same thing with AristoCraft. It was made to be compatible with LGB and of metric size but it is marked to the nearest foot.
A few millimeters won't be of concern to many but it can throw you right out if using precision design. 
No point using a computer if your data is measured with a potatoe...

By the way, it has everything to do with the original question but ignorance is the way for some. 

Andrew


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## chuck n (Jan 2, 2008)

Here in the non metric part of the world we have always used 4', 5', and 8' for R1,2, and 3. It is an approximation that works for us.


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## Garratt (Sep 15, 2012)

R1 is the answer to the specific question. 
You gave specific incorrect measurements so I corrected you.

Andrew


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## JerryB (Jan 2, 2008)

Although trackwork (especially outdoor, on the ground trackwork) will stand a lot of variance in dimensional accuracy, the fact is that trackwork is very geometry (and thus dimension) dependent. Using the manufacturer's accurate dimensions is most likely to ensure the best performance.

As Garratt wrote, 1200mm is actually 47.24". That is significantly different from 48". Track layers desiring excellent, trouble-free operation would always use the most accurate dimensions. I guess the corollary is that those who are okay with less than perfect operation will be satisfied with "an approximation." That isn't country or continent specific, but is engineering specific.


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## Dan Pierce (Jan 2, 2008)

When making modules with 4 foot lumber, track being less than 4 feet creates a problem.
So, I stick with the real track metric length.

Only exception to the metric measurement I have seen is the USA Trains switch which is 36 inches long. I was surprised when I measured it.


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## Totalwrecker (Feb 26, 2009)

I know folks who built narrow supports to inches and then had to rebend the track to fit.... they thought it was a bigger deal than none....


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## Greg Elmassian (Jan 3, 2008)

http://www.elmassian.com/trains/track-aamp-switches/lgb-track-a-switches


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## East Broad Top (Dec 29, 2007)

Let's be mindful of our tone, gentlemen. 

For all practical purposes, the "R1" curve by LGB, Aristo, USA, Bachmann, Lionel, Hartland, etc. has always been described by modelers in the US as being 4' diameter (2' radius) despite it not being _exactly_ that. Same for their other curves. LGB's 1600 curve is often described as being 4' radius (8' diameter) despite it being a few inches shy of that. It's been that way pretty much since day 1. Likewise, the straight sections of track have always been described as "one-foot," "two-foot," etc., despite them not being _exactly_ that. 

If you line up the "one-foot" sections of track from USA, Aristo, Bachmann, LGB, Piko, etc., you'll find them not to be the same length, and also likely not to be either exactly 12" _or_ 300mm. So if the manufacturers are taking liberties with the geometry of their track, perhaps that gives us latitude to do the same?

Later,

K


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## chuck n (Jan 2, 2008)

Thanks "K". That is all I was trying to say. Sorry to all if my response got off the mark.

Chuck


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## Garratt (Sep 15, 2012)

And this ignorant nonsense trickles down to software developers like AnyRail where the AristoCraft track is all precisely incorrect. Go figure...

Andrew


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## Greg Elmassian (Jan 3, 2008)

I did not title my link, but the actual and the "nominal" dimensions are shown in a nice table (well, I think it's nice ha ha!) I think both the nominal and the precise dimensions are needed at various times.

Here's the link again: http://www.elmassian.com/trains/track-aamp-switches/lgb-track-a-switches

Also, for years LGB themselves did propagate incorrect information, I think it was on their R3.

Regards, Greg


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## Garratt (Sep 15, 2012)

Why argue the point when someone refines the exact measurement to someone else asking?
The discussion was never about what to call the different radii it was about the nominal manufactured measurement. Are you going to delete this comment too Mr Moderator? Ha!

Andrew


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## docwatsonva (Jan 2, 2008)

I just sit back, smile, and think that the number of largescale railroaders who actually read these forums and give a hoot about so-called experts who tout exact measurements are very much in the minority.

Doc


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## Greg Elmassian (Jan 3, 2008)

There's a couple of things here... the OP's question, and now morphed into nominal vs. exact measurements.

A very good point has been brought up... if you are planning a layout, you really need the exact measurements, and indeed, many track planning softwares do not have the exact measurements in them.

My personal experience was to cram the largest possible curves in a tight unforgiving back yard. So when my track plan (using Aristo sectional track) from RR-Track looked good, and I put it down on the ground, it did not fit. I found that the track planning software did not have good data, and the errors in the per piece dimensions multiplied by the number of pieces.

So it really depends on your personal experience and needs. The people lucky enough to have a lot of space and don't need track planning software are just that, lucky.

But denigrating people who don't have the same circumstances as you is bad form in my opinion.

Greg


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## Totalwrecker (Feb 26, 2009)

I never have been shy of too much knowledge, remembering is different. If it doesn't apply I let it slide, but hey it's nice of my friends to remind me...
I mentioned a friend who had to redo. Maybe it's better to irritate a few and save one...

What was I doing?

Gots to water the casting... see ya.


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## Greg Elmassian (Jan 3, 2008)

"Maybe it's better to irritate a few and save one..."

Amen... especially if he/she is a beginner...

Greg


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## BigRedOne (Dec 13, 2012)

For many practical purposes, it scarcely matters what the difference is.

- "Can I run these cars which say 'four foot minimum radius' on my R3?" The answer is probably yes, even if R3 is less than four foot.

- "I'd like an SD70; my room is 12 x 20, will it work?"

- "Will Pico track fit my LGB track?"

A lot of large scale manufacturing tolerances are abysmal. If I take enough curve sections to form a circle, and make a circle, there will be gaps where the rails don't butt flush; if I make the rails flush in each joint, the final piece won't make a circle ...

LGB switches match LGB curves, no matter what you call them.


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## East Broad Top (Dec 29, 2007)

What's the "exact" measurement of a piece of track? Let 20' of track sit in the hot sun all day long, and it's going to be longer than 20'. Curves expand outward in the heat, increasing the effective radius. We specifically engineer flexibility into our railroads to allow for this constant movement. That same flexibility is what allows us to compensate for discrepancies between "nominal" and "exact" track measurements.

People have been planning their railroads with nothing more than a compass, ruler, and rough estimates of how many sections of track they're going to need for decades. No "exact" measurements there. They draw the plan, stake out the garden, and lay the track. Unless something is abysmally off in the drawing or math, it generally fits pretty much as planned. Typically, any differences are easily compensated for with maybe a slight shift here, cut or short filler section of track there. 

That having been said, it's one thing for the modeling community to use generalizations when describing the sections of track. We know they're generalizations, and can plan accordingly. It's another for track-planning software to do the same. It's incumbent upon them to make sure what is in the software matches what comes out of the box of track when it arrives on your doorstep. It's not that the differences would be insurmountable--no more than any other planning method--but the presumption is that if you're using a template based on a manufacturer's specific product, that template should be as accurate as possible. 

Later,

K


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