RMweb Premium Hilux5972 Posted October 19, 2014 RMweb Premium Share Posted October 19, 2014 Hi all I am trying to find an OO Gauge moulding of an AWS plunger unit as fitted to Olton Hall but have not had any luck. Can anyone point me in the right direction? Thanks Ps sorry about thi pic quality, taken from a video Link to post Share on other sites More sharing options...
bubbles2 Posted October 19, 2014 Share Posted October 19, 2014 Me too. Mainly trains did one a while ago but has been unobtainable for some time now. Link to post Share on other sites More sharing options...
RMweb Premium phil-b259 Posted October 19, 2014 RMweb Premium Share Posted October 19, 2014 Hi all I am trying to find an OO Gauge moulding of an AWS plunger unit as fitted to Olton Hall but have not had any luck. Can anyone point me in the right direction? Thanks Ps sorry about thi pic quality, taken from a video Erm, the correct description is an "AWS aerial", not a "plunger" - the AWS system being a non contact electromagnetic system. The GWRs forerunner called ATC did involve physical contact between the loco (though no "plunger" arrangement) and the "ATC ramp" which meant regular replacement of the contact surfaces was required. Link to post Share on other sites More sharing options...
Titan Posted October 19, 2014 Share Posted October 19, 2014 Not quite, the correct term is "AWS receiver". It is not an aerial, but a coil that gets a current induced in it by the very (and I really do mean very!) strong magnets in the track. There will be a permanent magnet in the track with IIRC a north* pole presented upwards. This is followed by an electromagnet, which when energised presents the opposite (south*) pole when turned on. So for a warning the AWS just sees one pulse, for clear two opposite pulses. We had a strong magnet for testing them on depot, show one end only and you should get a warning, show one end and quickly flip it over to show the opposite pole and you should get a clear. And if you are stupid like me put the magnet into your overalls pocket next to your wallet. Took me a while to work out why all my cards stopped working... * these may be the other way around Link to post Share on other sites More sharing options...
RMweb Premium Hilux5972 Posted October 19, 2014 Author RMweb Premium Share Posted October 19, 2014 Thanks but I was not asking what it is called. The photo shows what I am talking about. I'm asking if anyone knows where I can find a moulding of one. Link to post Share on other sites More sharing options...
Free At Last Posted October 19, 2014 Share Posted October 19, 2014 Hilux5972, on 19 Oct 2014 - 10:53, said:Thanks but I was not asking what it is called. The photo shows what I am talking about. I'm asking if anyone knows where I can find a moulding of one. If you don't know what it is called how are you going to order one if someone were to tell you a supplier, will you send them the photo and say I want one of those please? Now you know what it is called you can be more sure of getting the correct part. Link to post Share on other sites More sharing options...
RMweb Premium Hilux5972 Posted October 19, 2014 Author RMweb Premium Share Posted October 19, 2014 Well I still dont know what it's called. Someone said it's an AWS aerial, someone said an AWS receiver. From what I know of its operation, when it passes over a magnet in the track, it plunges downwards to meet it. Hence AWS plunger. And it has also been called that a few times by various modelling magazines. So I'm still completely lost as to what it is Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted October 19, 2014 RMweb Gold Share Posted October 19, 2014 Well I still dont know what it's called. Someone said it's an AWS aerial, someone said an AWS receiver. From what I know of its operation, when it passes over a magnet in the track, it plunges downwards to meet it. Hence AWS plunger. And it has also been called that a few times by various modelling magazines. So I'm still completely lost as to what it is It is a static piece of kit on a loco - no moving parts in the receiver itself because (as Titan explained) it is merely there to sense the magnetic effect of the AWS magnets sitting in the four foot. The GWR system did involve physical contact between the pick up shoe on the engine and the ramp in the four foot therefore the pick-up shoe or plunger had to be capable of movement. As is visible in several pics on the page linked below 'Olton Hall' appears to have an AWS receiver mounted at the leading end of the bogie (possibly mounted on an assembly fixed to the back of the buffer beam?). http://flickrhivemind.net/Tags/5972,harrypotter/Interesting Link to post Share on other sites More sharing options...
Titan Posted October 19, 2014 Share Posted October 19, 2014 Well I still dont know what it's called. Someone said it's an AWS aerial, someone said an AWS receiver. From what I know of its operation, when it passes over a magnet in the track, it plunges downwards to meet it. Hence AWS plunger. And it has also been called that a few times by various modelling magazines. So I'm still completely lost as to what it is Well I would hope that having actually worked and maintained the things when I was with British Rail, i.e. I know exactly what I am talking about, my opinion would carry more weight than a modelling magazine or two, as indeed should Stationmasters'. It does seem that you don't realise that there were two completely different systems, The GWR ATC which used ramps and plungers, and the one that you actually want - i.e. the one in the photo, which is the BR AWS with track magnets and receivers and no moving parts, and seem to be getting the two muddled up. If you mix the terminology up you stand very little chance of getting what you want. Link to post Share on other sites More sharing options...
RMweb Premium Hilux5972 Posted October 19, 2014 Author RMweb Premium Share Posted October 19, 2014 Ok so it is a BR AWS receiver I am looking for? Does anyone know where I am likely to be able to find one of those. Link to post Share on other sites More sharing options...
Andy M Posted October 19, 2014 Share Posted October 19, 2014 Hilux, I'm afraid you're out of luck regarding a currently available casting for an AWS Receiver (GW or BR). In the past they have been produced by Mainly Trains, Crownline and David Geen as well as in kits from the likes of Westward, Finney and Mitchell. I have dropped hints with RT Models amongst others about adding one to their range. The last few I have needed have had to be fashioned from layered plasticard. You could scour the exhibition sales tables and e-bay for them but your best bet is good old DIY! In this instance I would love to be proved wrong and someone highlight a source. Regards, Andy. Link to post Share on other sites More sharing options...
28XX Posted October 19, 2014 Share Posted October 19, 2014 A good view of the ATC system here. 2969543689_2ecc777002_z.jpg (JPEG Image, 640 × 456 pixels) The AWS receiver housing is an alumnium cylinder reminicent of a cake tin, about 9" in diameter. Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted October 19, 2014 RMweb Gold Share Posted October 19, 2014 Some background and details of how BR AWS works here http://dickthesignals.co.uk/onewebmedia/19%20AWS.pdf Link to post Share on other sites More sharing options...
Titan Posted October 19, 2014 Share Posted October 19, 2014 They are the other way round: permanent south, with the north de-energised for restrictive aspects etc. and energised for clear indications, but we would have needed deep pockets for our test magnet though as it came attached to the end of a four foot or so long fibreglass pole! Back to the OP couldn't a reasonable approximation be lashed up from some sheet plasticard and plastruct or such like channel and round sections, the lowest point of which would be around a nominal scale 6.5 inches above rail head level? Oh well, I could not remember and it was a fifty/fifty shot! When we were testing them the trains were above a pit at the depot, so we popped underneath with the hand held magnet, which would fit in the pocket. We did have the ones with the long handle for testing if it needed to be done when the unit was on the stabling sidings, so you could reach without going under. Link to post Share on other sites More sharing options...
RMweb Premium Hilux5972 Posted October 20, 2014 Author RMweb Premium Share Posted October 20, 2014 I had a feeling I may have to scratch build it. Thanks for the help everyone Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted October 20, 2014 RMweb Gold Share Posted October 20, 2014 Don't forget that most AWS fitted steam locos hat a shield to stop the coupling swinging back and smashing the receiver. I don't know if any of the ex GWR locos were fitted with dual ATC/AWS equipment before withdrawl, I very much doubt it. I think it was only done for mainline diesels allocated to WR sheds or regularly operating over WR ATC fitted lines like those in the West Midlands transferred to the LMR. GWR steam locos had a hook to hold up the coupling so that it didn't hit the ramp and damage it or short circuit the batteries if energised. The last ATC track equipment was taken out of use at Stratford-upon-Avon in the late 1970s. Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted October 20, 2014 RMweb Gold Share Posted October 20, 2014 A good view of the ATC system here. 2969543689_2ecc777002_z.jpg (JPEG Image, 640 × 456 pixels) The AWS receiver housing is an alumnium cylinder reminicent of a cake tin, about 9" in diameter. The ATC plunger could also be under the cab, IIRC it was there on all of the Collett and Hawksworth 4-6-0 tender engines. Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted October 20, 2014 RMweb Gold Share Posted October 20, 2014 Don't forget that most AWS fitted steam locos hat a shield to stop the coupling swinging back and smashing the receiver. I don't know if any of the ex GWR locos were fitted with dual ATC/AWS equipment before withdrawl, I very much doubt it. I think it was only done for mainline diesels allocated to WR sheds or regularly operating over WR ATC fitted lines like those in the West Midlands transferred to the LMR. GWR steam locos had a hook to hold up the coupling so that it didn't hit the ramp and damage it or short circuit the batteries if energised. The last ATC track equipment was taken out of use at Stratford-upon-Avon in the late 1970s. As far as I know all ex GWR design steam locos had gone long before the WR started the conversion programme to AWS and in any case back in steam days there was nothing to prevent a loco without, or having defective, ATC or AWS going into traffic so lack of it didn't matter. Link to post Share on other sites More sharing options...
Retro_man Posted October 20, 2014 Share Posted October 20, 2014 Cavendish used to supply white metal GWR ATC shoes - CP41 - 6 per pack. I have 6 packs available at £2 per pack and if anyone is interested please PM me. Please note I am located in Canada and Canada Post charges $10.00 for Small Packet Airmail whether I mail 1 or all 6 packs. Steve PS - All 6 packs are now spoken for and I could have probably sold another dozen if I had them :-) The power of RMWeb! Steve Link to post Share on other sites More sharing options...
45125 Posted October 20, 2014 Share Posted October 20, 2014 The item shown on Olton Hall is an aerial, it hows the aerial for theTPWS unit. As it is not that clear a photo it may even be a combined AWS/TPWS unit. If fitted with BR AWS it is a receiver, if its TPWS only equipment it is an aerial. Regards Al Taylor Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted October 20, 2014 RMweb Gold Share Posted October 20, 2014 The ATC plunger could also be under the cab, IIRC it was there on all of the Collett and Hawksworth 4-6-0 tender engines. Then I find one of my own pictures of a Manor which appears to have something at the front. DOH!! Link to post Share on other sites More sharing options...
ozzyo Posted October 23, 2014 Share Posted October 23, 2014 The ATC plunger could also be under the cab, IIRC it was there on all of the Collett and Hawksworth 4-6-0 tender engines. Sorry not quit true as you have pointed out. The Kings all had the G.W.R. ATC plunger under the cab. The Castles started out with with the ATC plunger under the cabs, then from about 5023 it was mounted on the bogie.I don't think that any Castles had the ATC plunger mounted on the rear of the front buffer plank. The Halls at first had the ATC plunger mounted on the rear of the front buffer plank up to about 5919 /20, after this it was mounted on the bogie. If you can't see the front of the loco one of the best ways to see if the ATC plunger is mounted on the buffer plank is the ATC conduit, if it has a small junction box like in the photo below it (the ATC plunger) will normal be mounted on the bogie, I have also found these two photos of a Hall from the same batch showing buffer plank mounted ATC plungers (or the frames for them). In this photo of 4955 it shows the normal G.W.R. type of ATC plunger, In this photo of 4953 it shows the same type of framework but modified for a B.R. AWS receiver, HTH OzzyO. Link to post Share on other sites More sharing options...
69843 Posted October 23, 2014 Share Posted October 23, 2014 I know it doesn't answer the original question, but this view shows that 5972s setup is the same as 4953 above (you can zoom in quite well on this picture) http://locoyard.files.wordpress.com/2012/08/london-hyde-park-5972-olton-hall-hogwarts-express-1.jpg?w=900 Edit: Additional view here http://www.anticsonline.co.uk/l.aspx?k=13887 Link to post Share on other sites More sharing options...
ozzyo Posted October 24, 2014 Share Posted October 24, 2014 I know it doesn't answer the original question, but this view shows that 5972s setup is the same as 4953 above (you can zoom in quite well on this picture) http://locoyard.files.wordpress.com/2012/08/london-hyde-park-5972-olton-hall-hogwarts-express-1.jpg?w=900 Edit: Additional view here http://www.anticsonline.co.uk/l.aspx?k=13887 Interesting photos of 5972 in that it shows a post preservation modification to how the ATC / AWS plunger / receiver has been mounted. In the photo below of 5973 you can see that it's mounted on the bogie. The tell-tale that shows that the plunger / receiver should be mounted on the bogie is that both locos are missing the row of rivets to the left and right of the coupling hook, also by the time of the photo of 5972 she has a steam heat pipe on the front buffer plank. OzzyO. PS. a photo showing the ATC plunger in use on 5956. Link to post Share on other sites More sharing options...
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