MoonMonkey's findings and thoughts

On 24/08/2021 at 16:09, JimC said:

No such luck, however: 
https://www.scalemodelscenery.co.uk/lx237-oo-engines-must-not-pass-this-arch-sign-gwr-pack-of-2-oo4mm176-8029-p.asp

Thanks for the pointer to these signs.  I ordered some and finally got them onto the bridge!... Nice products, and even better - they come ready coloured.  This was great as they are delivered better than I could paint them.  I also got a pack of 'beware of the trains' signs which are also ready-finished, one of which is just inside the arch.   I did give them a bit of weathering powder/spray varnish.  No link to supplier (Scale Model Scenery), just a happy customer!  (ps, yes, I know it isn't a GWR loco, it was just here when I took the photo!!!)    

I meant to upload this photo too - shows the sign better! 

On 25/08/2021 at 09:40, Dickon said:

Edit: The minimum size was 300mm square.

That sounds about right and although I've seen plenty of them in real life when at work, I don't think I've ever seen one more than about a foot square (so 300mm is about right).

 

Your tiny arch seems to be something that was originally built for another purpose and was subsequently used for railway purposes when the yard etc. expanded.

 

Your 'Engines must not pass this point' sign notwithstanding, you should still have a Limited Clearance sign in place on one of the vertical faces adjacent to the small arch.

 

Edited October 22, 2021 by Captain Kernow

That red/white check sign looks to be BR though judging by the text font and general style. The OP needs something GWR era.  There were surely a good number of such restricted structures, albeit more height than width: someone must be able to dig up an example. And if no-one can find an example - then no-one is in a position to show the current setup is incorrect!

I just had a browse through a railwayana site, and while they had a number of those BR limited clearance squares, I didn't succeed in finding anything that was any earlier. And its not as if having to add an additional sign will be a great disaster should evidence ever turn up. There were a few "railway company locomotives must not  pass this point" which presumably are also private sidings. But for my money that sign looks neat.

Edited October 22, 2021 by JimC