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Turnout Terminolgy for newbies

Harry2013

By Harry2013,
in Layout & Track Design

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Harry2013

Harry2013

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Since I know nothing about track terminology I have to make notes.

 

I havent been able to find an image that clearly identifies all the different parts of a turnout.

 

So I have attempted to make my own.

 

The only things I have nt labeled are the sleepers - since I do know what they are, and the throw bar since I'll need a separate image to show all the detail.

 

So in the image below, have I mislabeled or forgotten anything ?

 

Turnout-parts.jpg

The various other kinds of turnout may well have parts not included in this basic image, but I ll address that issue as and when I need to.

 

Thanks

Harry

 

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kevinlms

kevinlms

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This site doesn't provide you with information on terminology, but it my help you with the overall dimensions of various Peco turnouts.

 

http://rmcq.org.au/worksheets_free/peco_turnout_dimensions.pdf

 

 

From your dimension at the bottom of diagram, the point you've labelled is a small radius LH point, code 75 Electro frog.

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Grovenor

Grovenor

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The letters A, B, C etc. (up to J or K) represent standard switch designs, ie the moving blades, starting with a short version suitable only for sidings and getting progressively longer until J or K are for very high speed turnouts. The numbers are for the crossing (frog) angle as 1 in 7, 1 in 8 etc, the larger the number the smaller the angle and the longer the turnout. Switches can be combined with different crossing angles within limits by varying the radius of the closure rails between switch and crossing. So you may have A4 to A7, B6 - B9, C8 - C12, D10 - D16, E14 - E18, F20 - F24, G24 - G28 etc. Most model turnouts are in the A and B sizes but most RTP versions, eg Peco have invented their own geometry in approximately that size.

Regards

Keith

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Paul Cram

Paul Cram

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If I may ask a question I was wondering what A7, B8, C9 were? The are mentioned in the RTL 00 gauge track in the Smaller Suppliers section in relation to different size turnouts but what do they actually mean?

A B C etc refer to the length of the switch rails A being the shortest. The 7 8 9 etc is the crossing angle expressed as a ration e.g. 1:7 1:8 etc

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Harry2013

Harry2013

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This site doesn't provide you with information on terminology, but it my help you with the overall dimensions of various Peco turnouts.

 

http://rmcq.org.au/worksheets_free/peco_turnout_dimensions.pdf

 

 

From your dimension at the bottom of diagram, the point you've labelled is a small radius LH point, code 75 Electro frog.

Thanks Kevin, that link looks v useful. I used a Peco template as the basic image.

Might as well get the spellings right as well as the terminology - it's guard not gaurd. But I usually see them referred to as check rails.

Thanks Rod, I missed that one, the image that Coombe Barton linked to is way more detailed than mine (and they also call them check rails).

 

Even so the process of making my own does help me to remember.

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Grovenor

Grovenor

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E.g. "frog" is a model term which is "crossing" in the real world.

Crossing is a technical term for the items concerned, but frog is also a real world term, more so in North America than here and perhaps somewhat old fashioned, with English used on railways in many countries over almost 200 years there is almost always more than one word for any given item, and often modellers use a different version to the one used by the big railway in their country.

Hands up those who can identify the "crotch frog", which term does appear on real world track drawings.

Regards

Keith

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phil-b259

phil-b259

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Crossing is a technical term for the items concerned, but frog is also a real world term, more so in North America than here and perhaps somewhat old fashioned, with English used on railways in many countries over almost 200 years there is almost always more than one word for any given item, and often modellers use a different version to the one used by the big railway in their country.

Hands up those who can identify the "crotch frog", which term does appear on real world track drawings.

Regards

Keith

 

In the UK, while non railway people may well call it a 'frog' if you approach a p-way or S&T man with such terminology there is a very good chance they won't have a clue what you are going on about. On the real thing I have never seen the slightest bit of evidence that 'crossings' have been called anything other than 'crossings' crossings right from the boardroom down to the shovel holder.

 

As to the term "crotch frog" - can you please enlighten us. It certainly has not appeared on any railway documents I have seen, nor have I ever heard anybody use the term. I could hazard a guess it is something to do with switch diamonds but thats probably not right.

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Fat Controller

Fat Controller

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'Frog' appears in the glossary at work, alongside 'crossing' as a translation of 'couer'- I quite like the French term myself. I had to translate 'talonné des aiguilles' for someone this morning, after a track machine (pesky critters) did just that as we were winding up the night shift- to save you looking, it's 'trailing the points'. I hope there was a spare point machine in the stores.. The colleague who had been asked to send out the announcement was a bit confused, as she couldn't think what stiletto heels (talons aiguilles) had to do with it..

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shortliner

shortliner

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frog is also a real world term, more so in North America than here and perhaps somewhat old fashioned,

...and to add to that re-railing frogs are often seen hanging on the sides of steam tenders and shortline diesels in USA - to help get de-railed equipment back on line in the minimum time
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Grovenor

Grovenor

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As to the term "crotch frog" - can you please enlighten us. It certainly has not appeared on any railway documents I have seen,

Google finds it! http://books.google.co.uk/books?id=X6YXAAAAYAAJ&pg=SA4-PA43&lpg=SA4-PA43&dq=crotch+frog&source=bl&ots=eBcuQQyneu&sig=ytMoFVAk_WgOuk-Djaci8AHj6wQ&hl=en&sa=X&ei=2xfDUtecBuXX7Aa4toCQBg&ved=0CDMQ6AEwATgK#v=onepage&q=crotch%20frog&f=false

regards

Keith

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tender

tender

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Hi Folks,

 - not sure if it's relevant but I found a useful guide to Peco dimensions / part numbers / scales from our Aussie colleagues:

http://rmcq.org.au/worksheets_free/peco_turnout_dimensions.pdf

Cheers, Steve O.

That's an interesting table Steve. It's a pity it doesn't express the frog angle and switch blade length in the more normal 'B7' type format.

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Grovenor

Grovenor

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Most model turnouts are in the A and B sizes but most RTP versions, eg Peco have invented their own geometry in approximately that size.

From my post above, hence:

It's a pity it doesn't express the frog angle and switch blade length in the more normal 'B7' type format.

Which it can't because they are not designed that way, the switches are not actually A or B and the crossings are not to recognisable 1:x dimensions. Even the 12 degrees given for the 00 turnouts is not actually the crossing angle but the angle of divergence at the fishplates, the actual crossing angles are different of each turnout size.

Keith

NB. The B7 etc format is specifically British so would not help those in other countries.

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