'sharp' turnouts in termini

[Derekstuart]

I know there are a few rule of thumb guides to determine what size of turnout is appropriate for a given location, and there are going to be exceptions to these 'rules'.

 

I have seen a photo on a NER branch terminus of a tandem turnout, with the first turnout being quite a short, sharp one.

 

I have tried many combinations in Templot to recreate what I can see and a B5.5/B8 is the only combination that exactly matches.

 

The turnout was used as part of a relief crossing so would only have had trains infrequently and also as a loco-only run around loop. It would have had B1/K1's using it and later on I know Deltics crossed it on railtours (loco only) and it is possible that an EE4/40 would also have crossed it again on railtour.

 

On the basis of the stock crossing it, is it possible that it could be a B5.5? Other sources have suggested that it would be virtually impossible for a coupled steam engine or long bogie diesel to cross it at all.

 

Any opinions would be appreciated. Thanks

[martin_wynne]

On the basis of the stock crossing it, is it possible that it could be a B5.5? Other sources have suggested that it would be virtually impossible for a coupled steam engine or long bogie diesel to cross it at all.

 

Hi Derek,

 

It seems unlikely but not impossible (moving at walking pace, with a lot of flange squeal). But are you perhaps mis-reading the tandem? It is very common in a double-sided tandem turnout for the middle crossing to be 1:5 or thereabouts. That's not the same as a 1:5 turnout for radius.

 

If it is a 1:5.5 turnout I think the likelihood is vanishingly small that the switch is an REA "B". It may perhaps be an "A", but it's more likely to be a loose-heel switch. Have you tried in Templot with a 9ft or 12ft switch, or one of the curved switches? That would also ease the radius.

 

regards,

 

Martin.

[Derekstuart]

Hello Martin I think there is a little confusion on my part as to the terminology you are employing- when you say "middle crossing" do you mean the extra partial template that we superimpose?

The tandem is made up in Templot of B5.5, B8 and the third crossing (the partial template is also 8). These are the only combination that seem to match the photo.

 

All four blades are heel-less/ spring blades and by counting slider chairs are B's. The only other combination that works is a B6/B9, but there is no long entry straight on turnout 2 that would be expected with that combination.

 

A B6/B8 which was the original opinion when I asked on Templot club a year or so ago, but that puts wing rails closer to check rails and so on compared to the photo. Perhaps I might just have to compromise. There are many photos of this turnout, but people keep parking trains on it.

 

Thanks for the reply. I will go back and try again in Templot.

 

Hi Derek,

 

It seems unlikely but not impossible (moving at walking pace, with a lot of flange squeal). But are you perhaps mis-reading the tandem? It is very common in a double-sided tandem turnout for the middle crossing to be 1:5 or thereabouts. That's not the same as a 1:5 turnout for radius.

 

If it is a 1:5.5 turnout I think the likelihood is vanishingly small that the switch is an REA "B". It may perhaps be an "A", but it's more likely to be a loose-heel switch. Have you tried in Templot with a 9ft or 12ft switch, or one of the curved switches? That would also ease the radius.

 

regards,

 

Martin.

[martin_wynne]

Hi Derek,

 

I've looked at a B-5.5 (with generic V-crossing) and it's not as bad as it sounds. But I still think it is unlikely to be a "B" switch. The NER had flexible switches in addition to loose-heel switches, which may account for the number of chairs.

 

If you post a picture, or your .box file, or a link to the Templot discussion, we can have another look.

 

regards,

 

Martin.

[Derekstuart]

Thank you Martin.

 

Thanks to your comments there, I have just tried another combination. A B5.75 and B8 BOTH curviform. The photos aren't at a suitable angle to see if that matches up, but I will try plotting the whole thing onto the OS map and see if both being curviform matches the contours.

 

Unless of course there is a "rule" about them both being curviform.

 

I am sure they are both B blades or a NER specification so close as in model terms makes no difference.

 

Thanks again for the suggestions. I will try again and if I think I have it right, post the box files as suggested.

Hi Derek,

 

I've looked at a B-5.5 (with generic V-crossing) and it's not as bad as it sounds. But I still think it is unlikely to be a "B" switch. The NER had flexible switches in addition to loose-heel switches, which may account for the number of chairs.

 

If you post a picture, or your .box file, or a link to the Templot discussion, we can have another look.

 

regards,

 

Martin.