RailWest

This might prove of interest also.....

The attached photo apparently shows a MR 'improved' underbolt, tho' I've no idea either how it worked or what the 'improvement' was :-(

AIUI it was a mechanical bolt on the distant lever in the box on rear, preventing the chap in rear clearing his distant without prior release from the box in advance. I am guessing that the term underbolt arose because it was fixed to the lever tail below (under) the operating floor?

>>>>I'm guessing I'd need a "limit of shunt" board on the platform starter signal post too?... No :-) The signal is your limit of shunt. LoS boards are for wrong-direction movements in locations where otherwise there would be no signal.

Make a 'comestic' trap point. Model the switch blades as if they were in closed position. IMHO that's better than nothing.

The trap would be on the same lever as the entry point. The FPL would need a lever. It is arguable whether or not the FPL lever could act as the release, or that would require its own lever. Given that the GF would be worked by a guard or shunter 'on the spot' in a position where he could give hand signals, then I would questions whether any shunt signals would be necessary. Depends in part perhaps on the imagined date of installation.

Well, the minimum that you would need is a basic trap-point, but nothing more - no spur. Looking at the photo there appears to be a switch blade on the RH side, so as there would needed to have been one on the LH side at least then it would appear to have been a 2-blade trap.

A quick sketch would help a lot to have a better understanding :-) Why do you think it would be on a GF rather than worked from the SB?

Trap, not catch, as it was facing for exit traffic :-) The signal-diagram merely shows it as a simple trap-point, tho' such things are not always truely representative of what was actually 'on the ground'. However the attached image - a rather crudely-enlarged snip from what IIRC was a photo from the SWC's Eyres collection - does suggest to me nothing more than a plain trap. You may wish to form your own opinion :-)

IMHO this one looks like just a pair of rails sunk into the wall, as opposed to the usual alternative of a sleeper or similar. As regards the Up SIding, do not forget that this appears to have been lengthened at the south end when the signal-box by the junction was abolished, so it could have been either the original one relocated or a new one provided at the time.

† - well, you learn something every day here - thanks!

RCH code P was in fact Passengers and Parcels. P* was Passengers but no parcels. P with a 'dagger' suffix (sorry, don't have that symbol!) was Parcels, but no passengers.

AIUI you are now looking at Blaenavon (Low Level) GWR again then? The locking table tells us that the backing signal 22 required points 9 reverse. Similarly No 23 also required 9 reverse. I don't know what the gradient is there, but if it's downhill going to the left then I would suggest that the 'balanced points' were to protect the single-line from any runaways for the 'mineral line' platform road, as there would be no wrong-road signalled movement - unless, of course, a train coming in on the mineral line platform from the RH end over-ran and SPADed signal 22. I doubt that they would have provided a double-slip unless the traffic really demanded it - complicated to install and maintain and it would need a FPL for LH-bound trains. Maybe a single-slip at best, to allow LEs to run back between the shed and the passenger platform, but the other part of a double-slip - go between the lower line and the upper line - would have no use at all.

AIUI 'balanced points' is simply another term for points which are not worked from a signal-box or ground, but essentially are sprung-loaded or otherwise biased to normally lie in one direction, but could be pushed over when trailed. In the location indicated, almost certainly a set of spring-loaded trailing catch points that can be trailed shut by a train running from L to R, but otherwise lie 'open' to prevent wrong-direction movements from the upper platfrom line back onto the LH single line.

I wonder if the OP has been influenced by the GWR Blaenavon, where the upper platform line appears to have been goods-only and passenger traffic used the lower platform only?