Jump to content
 

Mid-Cornwall Lines - 1950s Western Region in 00


St Enodoc
 Share

Recommended Posts

  • RMweb Premium
On 10/07/2021 at 20:37, 5BarVT said:

Might be misunderstanding here, if the bolt is fitted head up down through the plywood, don’t you need a nut to hold the coil in place?

Or do I misunderstand how gravity works in Aus? :-)

Paul.

I think that was what Baz was describing. I prefer to screw from below (quiet at the back...) straight into the plywood, which doesn't need a nut.

 

1043959746_20080425002uncouplerinstalled.thumb.JPG.ec4850bdfd5fad57d90a170ac4ed67ae.JPG

Edited by St Enodoc
images restored
  • Like 6
  • Funny 2
  • Friendly/supportive 1
Link to post
Share on other sites

  • RMweb Gold
7 hours ago, St Enodoc said:

Track duly painted. Once it's dry, I'll clean off the rail heads and free up the points.

Did you spray or brush?

(Writing that made took me back to UK elections “I smoked but didn’t inhale” . . .)

Paul.

  • Like 1
  • Round of applause 2
Link to post
Share on other sites

8 hours ago, St Enodoc said:

Regarding no 200, I've no idea whether there was such a loco. I'm sure there was a coach or van though. I might look it up later.

It was a Barry Railway B Class 0-6-2T, built by Sharp Stewart and taken into GW ownership in 1922.

 

https://en.wikipedia.org/wiki/Barry_Railway_Class_B

 

...he said posting on page 201. Luckily there was a 201 0-6-2T as well. :)

Edited by Martin S-C
  • Like 4
  • Thanks 1
  • Round of applause 1
Link to post
Share on other sites

  • RMweb Premium
19 hours ago, 5BarVT said:

Did you spray or brush?

(Writing that made took me back to UK elections “I smoked but didn’t inhale” . . .)

Paul.

I just brushed the rails, Paul. Spraying inside the railway room is too complicated (I don't use an airbrush).

 

18 hours ago, Martin S-C said:

It was a Barry Railway B Class 0-6-2T, built by Sharp Stewart and taken into GW ownership in 1922.

 

https://en.wikipedia.org/wiki/Barry_Railway_Class_B

 

...he said posting on page 201. Luckily there was a 201 0-6-2T as well. :)

That's why it wasn't in the Wolverhampton or Swindon works/lot lists! Thanks.

Edited by St Enodoc
  • Interesting/Thought-provoking 1
Link to post
Share on other sites

  • RMweb Premium
5 hours ago, Martin S-C said:

It was a Barry Railway B Class 0-6-2T, built by Sharp Stewart and taken into GW ownership in 1922.

 

https://en.wikipedia.org/wiki/Barry_Railway_Class_B

 

...he said posting on page 201. Luckily there was a 201 0-6-2T as well. :)

..yep another Barry...

 

Baz

 

PS I will measure the bolts I use.( Been a bit busy umpiring between rain showers today.)

 

 

  • Thanks 1
  • Friendly/supportive 1
Link to post
Share on other sites

  • RMweb Premium
2 hours ago, Barry O said:

..yep another Barry...

 

Baz

 

PS I will measure the bolts I use.( Been a bit busy umpiring between rain showers today.)

 

 

Thanks Baz. Just as a matter of interest, did either of those appear on Cwmafon?

  • Like 1
Link to post
Share on other sites

  • RMweb Premium
5 hours ago, St Enodoc said:

Thanks Baz. Just as a matter of interest, did either of those appear on Cwmafon?

There is a Barry B for Cwmafon, in somewhat fictitious BR livery.

203.JPG.5699cf413293e29a5b5f85f75e89468e.JPG

Seen here at Herculaneum Dock since Cwmafon is in storage at the moment - although I do have a tentative plan to revive it.

  • Like 12
  • Agree 1
  • Thanks 1
  • Friendly/supportive 1
Link to post
Share on other sites

  • RMweb Gold
On 05/07/2021 at 00:30, Martin S-C said:

So a trap point is designed to stop vehicles or trains in a siding fouling the main line and is usually worked as half of a crossover with the siding or loop access point (and a signal)? A catch point is an apparatus to catch runaways on grades out of sidings that has no other linked points or signals? Am I warm?

Long while since I popped in but great to see progress.  Now to the question  

 

1.  A trap point was intended to trap any unintended right direction movement towards the line it was protecting.  They were required where things like sidings and goods lines joined a line used by passenger trains but were also sometimes uded tp protect non-passenger lines if a particular risk had been identified.

 

2. A catch point was positioned on, or at the foot of, a rising gradient in order to catch any vehicles which had broken away and were running away, or going to run away in the wrong direction so potentially towards a following train.

 

On the GWR a slotted joint (aka a spring slotted point, spring slotted catch point  -  and no doubt a few other names) was a catch point which could also be closed (usually by rodding from a  signal box) in order to allow a legitimate movement to be made over it in the wrong direction without being derailed.   A particular speciality on the GWR (although I expect they existed elsewhere as well) at some  crossing stations on single lines was the arrangement of  a trap point and a catch point lying back to back and in that situation the catch point was usually of the spring slotted variety.

 

Examples of spring slotted  catchpopints in Cornwall existed (at one time or other)  could be found at at Nancegollan on the Helston branch;  Penryn on the Falmouth branch (which also had a trap point and catch point back-to-back);  Tolcarn Jcn, Goonbarrow Jcn, and Luxulyan (which also had a trap and catch point back-to-back) on the Newquay branch;  St Erth (on the branch line part of the layout);  St B;azey; and St Germans (which was something of an oddity as it is not readily explained because, unlike all the others, there was no signalled movement over it in the wrong direction).

 

Trap points were sometimes used at single line crossing stations (broadly from the 1920s onwards) as they allowed trains from each direction to run into the station/crossing loops simultaneously thereby saving a few minutes for the second train which would normally have been held outside at the Home Signal while the other train first ran into its loop and came to a stand.

  • Like 1
  • Thanks 1
  • Informative/Useful 11
  • Interesting/Thought-provoking 1
Link to post
Share on other sites

  • RMweb Premium
On 12/07/2021 at 01:41, The Stationmaster said:

Long while since I popped in but great to see progress.  Now to the question  

 

1.  A trap point was intended to trap any unintended right direction movement towards the line it was protecting.  They were required where things like sidings and goods lines joined a line used by passenger trains but were also sometimes uded tp protect non-passenger lines if a particular risk had been identified.

 

2. A catch point was positioned on, or at the foot of, a rising gradient in order to catch any vehicles which had broken away and were running away, or going to run away in the wrong direction so potentially towards a following train.

 

On the GWR a slotted joint (aka a spring slotted point, spring slotted catch point  -  and no doubt a few other names) was a catch point which could also be closed (usually by rodding from a  signal box) in order to allow a legitimate movement to be made over it in the wrong direction without being derailed.   A particular speciality on the GWR (although I expect they existed elsewhere as well) at some  crossing stations on single lines was the arrangement of  a trap point and a catch point lying back to back and in that situation the catch point was usually of the spring slotted variety.

 

Examples of spring slotted  catchpopints in Cornwall existed (at one time or other)  could be found at at Nancegollan on the Helston branch;  Penryn on the Falmouth branch (which also had a trap point and catch point back-to-back);  Tolcarn Jcn, Goonbarrow Jcn, and Luxulyan (which also had a trap and catch point back-to-back) on the Newquay branch;  St Erth (on the branch line part of the layout);  St B;azey; and St Germans (which was something of an oddity as it is not readily explained because, unlike all the others, there was no signalled movement over it in the wrong direction).

 

Trap points were sometimes used at single line crossing stations (broadly from the 1920s onwards) as they allowed trains from each direction to run into the station/crossing loops simultaneously thereby saving a few minutes for the second train which would normally have been held outside at the Home Signal while the other train first ran into its loop and came to a stand.

Thanks Mike and welcome back.

 

Did you pick up the discussion a page or two back about the catch point at Wheal Veronica? I'd be interested in your thoughts as to whether the lever would have been fitted with a tread plate (or similar) or whether the shunter just had to hold it over by brute force when something was passing over the point in the facing direction.

 

Thanks.

  • Like 2
  • Friendly/supportive 2
Link to post
Share on other sites

  • RMweb Gold
43 minutes ago, St Enodoc said:

Thanks Mike and welcome back.

 

Did you pick up the discussion a page or two back about the catch point at Wheal Veronica? I'd be interested in your thoughts as to whether the lever would have been fitted with a tread plate (or similar) or whether the shunter just had to hold it over by brute force when something was passing over the point in the facing direction.

 

Thanks.

Also Mike, how much consideration was given to which side of the track to insert the catch point, with regard to hillsides or other geographical or man-made features?

  • Like 2
  • Interesting/Thought-provoking 3
Link to post
Share on other sites

  • RMweb Gold
11 hours ago, St Enodoc said:

Thanks Mike and welcome back.

 

Did you pick up the discussion a page or two back about the catch point at Wheal Veronica? I'd be interested in your thoughts as to whether the lever would have been fitted with a tread plate (or similar) or whether the shunter just had to hold it over by brute force when something was passing over the point in the facing direction.

 

Thanks.

Crikey I look in for a few minutes and here we go again - but good to catch up (a bit)  and thanks for the welcome back. John

 

Usually a permanent hand lever working a catch point in a situation like this would have a treadle on the lever.  It doesn't seem to have been a situation where two way levers were used because that would have created a risk of the catch point being left closed because a two way lever box.  But having mentioned the use of a treadle there were certainly examples on coal stage gradients which weren't fitted with treadles - and had derailments in consequence.  However in a running line with revenue earning traffic passing over it a  treadle would make a lot of sense.  

Normally of course catch points did not have hand levers but where one was used in the facing direction a lever would have been provided so two more extended sleepers at the toe end ;) in order to mount the lever box and lever.

 

11 hours ago, Stubby47 said:

Also Mike, how much consideration was given to which side of the track to insert the catch point, with regard to hillsides or other geographical or man-made features?

Simples really Stu.  The throw off would be away from whatever is being protected from something running back through the catch point and derailing  - even if it would have meant something dropping down an embankment as it derailed.   So catch points never led towards the opposite line and if limited in where they could direct a runaway vehicle they could have a long, or very long, sand drag sitting partially in the foor foot (the best example I now of was at Abercynon which became a worked catch point after the line to Merthyr ewas singled.

 

A good example was the worked catch point at Coombe Jcn.  There's a photo on the Cornwall railways website - part way own this page with a DMU approaching it from Liskeard and it throws any runways well clear of the Looe line -

http://www.cornwallrailwaysociety.org.uk/looe-branch-including-moorswater.html

  • Like 1
  • Thanks 2
  • Informative/Useful 7
Link to post
Share on other sites

  • RMweb Premium
45 minutes ago, The Stationmaster said:

Usually a permanent hand lever working a catch point in a situation like this would have a treadle on the lever.

Thanks Mike, it's good to have that confirmation. I'll try to remember that when I eventually get round to installing the hand lever.

Edited by St Enodoc
  • Like 3
Link to post
Share on other sites

  • RMweb Premium
On 11/07/2021 at 20:53, St Enodoc said:

However, the H&M coils have a far lower resistance, just over 2 ohms, so on 19.5V they would overload the supply. I therefore decided to wire two coils in series, one to operate the uncoupler and the other as a dummy load. This brought the total resistance up to about 4.5 ohms so the maximum current will be just over 4A. I think that the power supply will cope with this for the short time that the coils are activated.

I'm having second thoughts about this. While the power supply should cope, the wiring and switches might not. As the Wheal Veronica uncoupler is independent of those at St Enodoc, I think I'll power it from a new circuit that will also serve Pentowan in future. I'll try out a few of the spare power supplies that I've hoarded over the years and see what works best.

  • Like 1
  • Interesting/Thought-provoking 2
Link to post
Share on other sites

  • RMweb Gold
5 hours ago, St Enodoc said:

I'm having second thoughts about this. While the power supply should cope, the wiring and switches might not. As the Wheal Veronica uncoupler is independent of those at St Enodoc, I think I'll power it from a new circuit that will also serve Pentowan in future. I'll try out a few of the spare power supplies that I've hoarded over the years and see what works best.

Do you know how many amps you need?  Then add a ceramic resistor to ‘manage’ the volts down (of suitable power as it will get hot).

Mind you power supplies are so cheap that reducing the volts might be easier.

Paul.

Edited by 5BarVT
‘and’ to ‘as’
  • Thanks 1
  • Interesting/Thought-provoking 2
Link to post
Share on other sites

  • RMweb Premium
8 hours ago, 5BarVT said:

Do you know how many amps you need?

That's what I'm going to try to find out! The existing sewing machine bobbin coils work fine at just over an amp but the configuration of the H&M coils is rather different. I'll try a few different voltages to see how low I can go and still activate the couplings. Watch this space!

  • Friendly/supportive 1
Link to post
Share on other sites

  • RMweb Premium
5 hours ago, St Enodoc said:

The existing sewing machine bobbin coils work fine...

 

If it ain’t bust, don’t fix it, as they say.   Are you trying to get something to work, that you don’t really need to, and might end up causing you more issues down the line?

 

The GW standardised for a reason...

 

Just asking the question :D

  • Thanks 1
Link to post
Share on other sites

  • RMweb Premium
40 minutes ago, Chamby said:

 

If it ain’t bust, don’t fix it, as they say.   Are you trying to get something to work, that you don’t really need to, and might end up causing you more issues down the line?

 

The GW standardised for a reason...

 

Just asking the question :D

Not quite that simple, Phil. I've run out of pre-made coils and getting the right size wire in the right lengths is harder here in 2021 than it was in England in 1996 (and a lot more expensive if I can). As I have a lot of old H&M motors I thought I'd give them a try, as suggested by my old mates from Leeds. Once I've chosen a voltage, all should be fine.

  • Like 4
  • Friendly/supportive 1
Link to post
Share on other sites

7 hours ago, St Enodoc said:

I'll try a few different voltages to see how low I can go and still activate the couplings. Watch this space!

 

A better solution might be a constant-current supply rather than a constant-voltage supply.  However, I imagine that you're working with what you have.

 

  • Interesting/Thought-provoking 2
Link to post
Share on other sites

  • RMweb Premium
3 minutes ago, aardvark said:

 

A better solution might be a constant-current supply rather than a constant-voltage supply.  However, I imagine that you're working with what you have.

 

Technically, that's probably correct. I don't think the absolute value of the current is too critical though. I plan to use a standard Jaycar plug-in supply once I've worked out which one I want (or even one of the pre-loved ones in my junk box if it suits).

 

Anyway, I was put off constant current supplies following my experience with the signal actuators (this topic passim), although that was probably more to do with my ham-fisted construction than the design principle. Much easier to use a constant voltage I think.

  • Interesting/Thought-provoking 1
Link to post
Share on other sites

  • RMweb Premium
1 hour ago, aardvark said:

My fledgling layout uses several of the following, which can operate as either Cv or Cc.  95% efficiency, so no issue with heat.

 

https://www.ebay.com.au/itm/292027273932

 

(other sellers are available)

Thanks. That looks similar to the constant voltage device that I use now for the memory wire actuators. I got that from a very helpful firm in Newcastle, Core Electronics (usual disclaimer):

 

https://core-electronics.com.au/adjustable-switching-power-supply-module-in-4v-35v-out-1-5v-30v-lm2596s.html

  • Interesting/Thought-provoking 1
Link to post
Share on other sites

42 minutes ago, St Enodoc said:

Thanks. That looks similar to the constant voltage device that I use now for the memory wire actuators. I got that from a very helpful firm in Newcastle, Core Electronics (usual disclaimer):

 

https://core-electronics.com.au/adjustable-switching-power-supply-module-in-4v-35v-out-1-5v-30v-lm2596s.html

 

Similar, but different. Apart from that, they're almost twins.

  • Funny 3
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...