Construction of a Test Track

[Noel]

I thought that trap points were to protect running lines against conflicting movements [mandatory where the running line was used by passenger trains, optional where the running line was goods only], while catch points were the [now redundant] sprung loaded points once found in the uphill line on double track gradients to stop unfitted stock which had broken away and run back. Points on the downhill end of uphill goods loops served both functions, although in that case they were worked as part of a crossover rather than sprung.

[grovenor-2685]

Yes Noel.
That is the situation.
However Martin believes that any blade/pair of blades not attached to a crossing should be described as a catch point regardless of whether it is functionally a catch or a trap. Its perfectly possible some railways have used such terminology in the past, terminology changes and can vary between engineers and operators at the same time.
Regards

[Allan Goodwillie]

Hi Colin,

catch.jpg

Not entirely sure if this is called a catch or trap point - it certainly is not sprung and worked independently from any other point, it has two blades as can be clearly seen and was on a gradient. Its purpose I assume is to catch any runaway from Scotts road yard which might have come racing down the gradient into their works and shed (Down to the left). The line was an independent coal line.

The Main line, as such, is climbing away to the right. The line was quite steep going down to the works. It is interesting to see that the point has two blades and would direct wagons into the side of the mainline embankment rather than on to the open land on the left and the continuing slope down to the works yard.

One of the interesting features on the North British was the use of multiple versions of trap points with single blades at the end of yards where they led out on to the main line. Pairs were quite common - worked in conjunction with the main line point on a single lever. One set in Largo led directly into the paraffin store! In Kirkcaldy which had a busy but cramped yard with a pair of 4-way points with accompanying inter-connecting traps. Howard would be ecstatic I am sure. I made some for Dubbieside about 50years ago which are still in place, but they no longer work as they were connected via the operating rods and when eventually the rods packed in I simply made them non-functioning, with the intention of replacing - I have never found the time since to do this I am afraid. The construction above I have completed during my recent track laying spree which I must photograph and put up on the thread.

The line was a goods only operation in later years although it once had a passenger service for its own workers in bygone days. (This being a possible red herring as I do not know what happened to the staff when the passenger train reached this end of the line.) Not too worried about definitions, but like to see them modelled if they should be there. One question I had about this particular item is that alongside the point on the embankment side there was a small retaining wall and I am not certain what the purpose of this was - it appears to have been made out of sleepers. It may have been put in there so anything running off would cause minimal damage to the embankment, or possibly it would stop any material from the embankment getting into the point and causing difficulty in operation - I have assumed the first to be more likely. The photo was taken after the line was closed.

[Martin Wynne]

Well, go on then, lets not make an exception now! Have you ever considered Martin, that it might just be because you are mistaken?

Hi Howard,

I think I must be mistaken in continuing to argue the point.

If you call a switch intended to derail as "trap points", what are you going to call a turnout when it leads to a sand drag? Both are serving the same operational "trap points" function as described in the Rule Book, but they are clearly different physical components.

Every permanent-way person I have ever talked to has called such a switch "catch points" (and every signalman "trap points"). I have seen manufacturing drawings for the things clearly labelled "Catch Points".

David Smith in his GWR track book has a whole chapter on "Catch Points" with many such drawings, and here is the first paragraph:

catch_points_gwr.png

Here is the relevant page from BRT3 (Edition 3, 1964, of the PWI handbook):

catch_points_brt3.png

In Edition 4 of 1971, all references have been changed to "Trap Roads" clearly under the influence of those who write the Rule Book. But no-one told the folks actually making the damn things, for whom they are, or were then, still the same "catch points" they had been making for years.

regards,

Martin.

[JFS]

I think I must be mistaken in continuing to argue the point.

Not at all - the debate is much more fun!

The wording from BRT is exactly the same as the 1956 edition (but there it is on page 124) and I suspect it was the same in the 1943 edition which I do not have. But from David Smith's reference and the BRT it is clear that the wording is being dragged kicking and screaming towards a common set of terminology which makes the distinction between (essentially) worked and unworked switches. My railway career did not start until the early seventies and by then the Rule Book and the General Appendix were pretty plain speaking in such matters.

Of course, in model railway terms, Run Away Catch Points would be a rare beats (perhaps "Sheep Pasture" has them?) whereas Trap/Safety Points are pretty common, so to refer to everything as Catch Points runs the risk to confuse I suggest.

All joking apart, I do think it is helpful if we try to use the "generally accepted" definitions in such matters - otherwise people who do not have the history are apt to get lost. I recently was looking through the instructions for a loco kit with working inside Stephenson's valve gear. The author clearly knew nothing about prototype practice because he had invented his own terminology for every single item, yet there was no diagram to illustrate which part was which. Now a builder might try to Google the real thing to find his own way round that - at which point he would be completely lost...

So why can't we just use the terms as they are illustrated on page 131 of the 1972 General Appendix - after all, they have been in use by most of the railway - if not the P-way - for at least 50 years!

Now where is Colin with the latest installment?

Best wishes,

[Martin Wynne]

So why can't we just use the terms as they are illustrated on page 131 of the 1972 General Appendix - after all, they have been in use by most of the railway - if not the P-way - for at least 50 years!

Hi Howard,

But this is a topic about P-way!

I don't have as copy of that to hand, but I'm guessing it refers to "trap points" without making any distinction between a single switch blade, a pair of switch blades, or a turnout (or even a slip) leading to a sand drag or similar dead end?

To the signalling and operating staff that distinction has no relevance. But it does when you are trying to create one in Templot, or digging out the ballast with a shovel, or sniffing the butanone.

This is a topic about track, not signalling or operating. So in this topic it is a set of catch points. If the operating staff want to use the same term for that and a similarly placed turnout, that's up to them.

cheers,

Martin.

[Tony Wilkins]

So now we have the definitive answer. It depends on who you ask
Regards
Tony.

[Tony Wilkins]

One of the interesting features on the North British was the use of multiple versions of trap points with single blades at the end of yards where they led out on to the main line. Pairs were quite common - worked in conjunction with the main line point on a single lever. One set in Largo led directly into the paraffin store! In Kirkcaldy which had a busy but cramped yard with a pair of 4-way points with accompanying inter-connecting traps. Howard would be ecstatic I am sure. I made some for Dubbieside about 50years ago which are still in place, but they no longer work as they were connected via the operating rods and when eventually the rods packed in I simply made them non-functioning, with the intention of replacing - I have never found the time since to do this I am afraid. The construction above I have completed during my recent track laying spree which I must photograph and put up on the thread.

Hi Allan.
A bit like this I presume.

Tandem with traps.JPG

Tandem turnout with assorted single and double bladed, er, safety points.
Regards
Tony.

[Martin Wynne]

So now we have the definitive answer. It depends on who you ask

+1

[Le Corbusier]

One of the interesting features on the North British was the use of multiple versions of trap points with single blades at the end of yards where they led out on to the main line. Pairs were quite common - worked in conjunction with the main line point on a single lever. One set in Largo led directly into the paraffin store! In Kirkcaldy which had a busy but cramped yard with a pair of 4-way points with accompanying inter-connecting traps. Howard would be ecstatic I am sure. I made some for Dubbieside about 50years ago which are still in place, but they no longer work as they were connected via the operating rods and when eventually the rods packed in I simply made them non-functioning, with the intention of replacing - I have never found the time since to do this I am afraid. The construction above I have completed during my recent track laying spree which I must photograph and put up on the thread.

Hi Allan.
A bit like this I presume.
Tandem with traps.JPG
Tandem turnout with assorted single and double bladed, er, safety points.
Regards
Tony.

Wow Tony .... that some piece of point work

[RobM]

Wow Tony .... that some piece of point work

Tim, you need to see the 5 way turnout Tony built for Green Street.....an even bigger wow!
Rob

[Tony Wilkins]

Wow Tony .... that some piece of point work

Tim, you need to see the 5 way turnout Tony built for Green Street.....an even bigger wow!
Rob

Cheers Rob,
I suppose I will have to post a picture of that now.
Regards
Tony.

[JFS]

I suppose I will have to post a picture of that now.

No need Tony - there is one here - and much else of interest for those who might not know of this site.

http://www.clag.org.uk/green14.html

Best WIshes,

[Le Corbusier]

I suppose I will have to post a picture of that now.

No need Tony - there is one here - and much else of interest for those who might not know of this site.

http://www.clag.org.uk/green14.html

Best WIshes,

[Tony Wilkins]

Hi Howard.
The CLAG site pictures did cross my mind and there are lots of pictures of other trackwork on Green Street there too. They are of course somewhat old now. The CLAG site is well worth a look as there is a wealth of information on there covering many topics.
Thanks.
Tony.

[Colin Parks]

One of the interesting features on the North British was the use of multiple versions of trap points with single blades at the end of yards where they led out on to the main line. Pairs were quite common - worked in conjunction with the main line point on a single lever. One set in Largo led directly into the paraffin store! In Kirkcaldy which had a busy but cramped yard with a pair of 4-way points with accompanying inter-connecting traps. Howard would be ecstatic I am sure. I made some for Dubbieside about 50years ago which are still in place, but they no longer work as they were connected via the operating rods and when eventually the rods packed in I simply made them non-functioning, with the intention of replacing - I have never found the time since to do this I am afraid. The construction above I have completed during my recent track laying spree which I must photograph and put up on the thread.

Hi Allan.
A bit like this I presume.
Tandem with traps.JPG
Tandem turnout with assorted single and double bladed, er, safety points.
Regards
Tony.

Hi Tony,

It looks like that template on which your excelllent point work stands was created with Templot, so what did the program say when you added the 'safety point' partial template?!

My understanding of the terms (prior to reading all the above posts) was: catch points caught and derailed runaway stock on running lines, and trap points would prevent runaways from reaching the running lines in the first place. Then I thought it was the opposite, now I do not really mind either way.

To change the subject, here is a picture of a FB turnout now with extended switches. To be honest, they are made 2mm over scale-length to avoid the messy and possibly impossible task of moving the timbers and narrowing the gaps to the required distance under the new rail joint positions. Since this photo was taken the rest of the 'long' switches have been installed and the improvement in appearance is remarkable (not to mention adding more flexibility into the equation) - if you do not look too hard at the timbering of course...

IMG_8745 (2).JPG

All the best,

Colin

[Martin Wynne]

My understanding of the terms was: catch points caught and derailed runaway stock on running lines, and trap points would prevent runaways from reaching the running lines in the first place.

Hi Colin,

That's a correct description of the function and purpose of the said items.

The actual physical components which provide these functions are often exactly the same thing in both cases, or very similar. The works drawings for manufacturing them are labelled "Catch Points", and that is what they are called by the folks who make them and lay them. Or at least they did, in BR days. I don't know what Carillion call them.

regards,

Martin.

[Le Corbusier]

To change the subject, here is a picture of a FB turnout now with extended switches. To be honest, they are made 2mm over scale-length to avoid the messy and possibly impossible task of moving the timbers and narrowing the gaps to the required distance under the new rail joint positions. Since this photo was taken the rest of the 'long' switches have been installed and the improvement in appearance is remarkable (not to mention adding more flexibility into the equation) - if you do not look too hard at the timbering of course...

IMG_8745 (2).JPG

All the best,

Colin

A good ruse I think Colin .... the difference in appearance is well worth the effort ..... excellent

[Colin Parks]

My understanding of the terms was: catch points caught and derailed runaway stock on running lines, and trap points would prevent runaways from reaching the running lines in the first place.

Hi Colin,

That's a correct description of the function and purpose of the said items.

The actual physical components which provide these functions are often exactly the same thing in both cases, or very similar. The works drawings for manufacturing them are labelled "Catch Points", and that is what they are called by the folks who make them and lay them. Or at least they did, in BR days. I don't know what Carillion call them.

regards,

Martin.

Carillion? Who were they?!

[Paul Willis]

My understanding of the terms was: catch points caught and derailed runaway stock on running lines, and trap points would prevent runaways from reaching the running lines in the first place.

Hi Colin,

That's a correct description of the function and purpose of the said items.

The actual physical components which provide these functions are often exactly the same thing in both cases, or very similar. The works drawings for manufacturing them are labelled "Catch Points", and that is what they are called by the folks who make them and lay them. Or at least they did, in BR days. I don't know what Carillion call them.

regards,

Martin.

Carillion? Who were they?!

Off topic, but for those of us of a certain age who remember listening to bands _before_ Kayleigh was a popular girl's name...

http://newsthump.com/2018/01/15/uk-construction-industry-in-crisis-after-government-mistakenly-bails-out-marillion/

It's all gone Fugazi...

Flymo

[Le Corbusier]

Off topic, but for those of us of a certain age who remember listening to bands _before_ Kayleigh was a popular girl's name...

http://newsthump.com/2018/01/15/uk-construction-industry-in-crisis-after-government-mistakenly-bails-out-marillion/

It's all gone Fugazi...

Flymo

[Terry Bendall]

My understanding of the terms (prior to reading all the above posts) was: catch points caught and derailed runaway stock on running lines, and trap points would prevent runaways from reaching the running lines in the first place.

In his book Railway Signalling and Track Plans Bob Essery mentions that Board of Trade inspection reports often described trap points or catch points as "safety points" which seems to be a good generic term. He also quotes a driver who described the difference as follows: "Catch points catch you if you run back, and trap points put you on the floor if you run too far forwards." The point about runaway stock was that the catch point derailed stock that was running backwards down a gradient

looking at pictures, both types of safety point may have one blade or two. Some safety points throw the vehicle off the track to the side of the track bed. From pictures this seems to be in instances where the safety point is designed to stop runaway sock when rolling backwards. This type of application usually required a sign reading "Switch" or "Catch Point" and there would be a lever to set the blades if wrong line working was needed. In other instances a short length of track lead to a sand drag or a set of buffer stops or even both. This type of application often seems to be used at the end of a loop.

Terry Bendall

[Colin Parks]

Hi Terry,

Thanks for your input. I would like to say 'definitive answer' but know better than that. The 'installation' that I have made is situated in a bay siding or platform road (if the project gets that far) and does the job of diverting stock away from a running line. This seems to accord with the driver's description of the function of "trap points" as quoted in the Essery book that you have quoted.

All the best,

Colin

[Allan Goodwillie]

Hi Colin,

Tony's photo shows a lovely piece of track work, but the layout of the traps was different, interestingly the ones I have on Dubbieside were also part of a tandem point - We have heavy snow just now so it is difficult to get into the garage and take a photo - but I will try to over the next few days. Mention of Fish reminds me of a rather nice moment when I had the museum in Melrose and I was working away doing something to Dubbieside one day and had a tape on in the background when this lady came round with a friend. She spent some time watching trains going by and showed some interest in what I was working on. She asked me whether I liked the music I was playing - a Marillion tape, the answer was yes and it was then that she told me proudly that Fish was her son - which of course led to a longer conversation altogether. - A very nice lady she was too. I often could be found late at night working in the railway room which was on the platform level of the station. It could be quite eerie as there were no platform lights on late at night and playing Kate Bush at full volume or Pink Floyd (the station was well away from any other habitation in the town) just added to the atmosphere.

[Terry Bendall]

The 'installation' that I have made is situated in a bay siding or platform road (if the project gets that far) and does the job of diverting stock away from a running line

Colin

If you beg, borrow or even buy Bob Essery's first book, Railway Operation for the Modeller, page 25 bottom has a picture of Blackwell station on the Lickey Incline which shows exactly what you require.

Terry Bendall