RichardH wrote:I am surprised no one has mentioned Plate 5.11 in LNWR Signalling (Foster), which shows a short arm bracketed out from the corner post of the box at Dolau.
That is interesting but I suspect that Plate 5.11 doesn't tell the whole story. There is no way that the corner post of the upper works of the STF box is man enough to support the signal even with the bracket. Examination of the mode of construction of L&NWR bracket signals reveals that there were two
horizontal beams which pass either side of the signal post, here the front horizontal clearly terminates in front of the box window but the rear horizontal must be in a plane beyond
the side of the box; if that beam runs externally right across the side of the box and is bolted to both corner posts on that side of the box (or if there is a metal tie-rod doing the same task), that would just about provide sufficient support for the relatively small signal. The box upper works would still have had to be well bolted on to the stone base.
A photograph of that side of the box would no doubt reveal the answer.
I have now found a (rather poor) photo of that side of the box which shows that the beam doesn't
extend across the side of the box. The photo appears to suggest that the normal handrail in front of the windows on that side may have been beefed up with a steel frame extending down either side and along the bottom of the window frame, but that might be no more than phantom shadows, the photo just isn't clear enough to be certain. If not, there is almost certain to be non-standard reinforcement of the framing internally, possibly in steel plate or angle.