Is the Overhead live...?

[great central]

What I have seen, and been impressed by, is a DCC loco which could raise and lower its pantographs.

 

Ws

 

Graham Clark's 7mm Netherwood Sidings has class 76s and now EM2s with pantographs operated by servos. I really must finish mine

Strange that the layout has only ever had one outing, never had another invite although it will re-appear at Nottingham sometime in the future.

[chaz]

I wonder if an innocent bystander (having never built a layout that had OLE) can comment?

 

I can see why you might want to make the wires work and if you really want to do it, that's justification enough. However it makes no difference at all to the look of a layout and may even force compromises that could otherwise be avoided. A friend of mine has an O gauge Stanier Duchess which has full, scale working valve gear between the frames. It's most impressive but when the loco is on the track it's completely invisible. Seems to me that similar arguements apply. How much of a model loco is steel? Probably only the axles and the motor spindle - but does it matter - of course not.

 

Railway models are superficial - their raison d'etre is to look as good as possible but like a film set they are a fraud and a deception. If you want to go the extra mile then there's no reason why you shouldn't but you may have to accept that you almost certainly won't be able to tell.

 

Chaz

[roythebus]

Having been in charge of one of the largest exhibition layouts that had overhead, the MRC's New Annington layout in the 1980's, that had overhead. It wasn't live (so we thought) as there were run-off ramps at the tunnel mouths.

 

We used a mixture of Sommerfeld and hand built for the "knitting" and yes, the pantographs touched the wires. It worked very well and dewirements were very few.

 

i said we thought the overhead wasn't live until one day a soldering iron was being used somewhere on the layout and a section of the overhead melted!! Investigation found that one of the mast bases had touched a common return wire under the layout which had somehow gone back to earth, causing some sort of short through the mains, and melted several soldered joints on the OLE! Be warned.

 

We decided to go for "non electrified" OLE because of the fiddle yard.problem.

[Gordon H]

We used a mixture of Sommerfeld and hand built for the "knitting" and yes, the pantographs touched the wires. It worked very well and dewirements were very few.

I recall coming along to Keen House to assist with some of the handbuilt headspans in the early days of OHLE construction on New Annington. At that time Jon Hewitt and Brian (can't recall his surname) were making a start on it, and I showed them how it had been done on 'High Gill' (and was being done on 'Carstairs'). That would have been about 1986 after High Gill had appeared at IMREX.

 

Short story:

Around the same time it was Roy who suggested High Gill as a candidate to appears on a BBC TV kids programme called 'Corners' to answer some questions about how signalling worked. This duly happened, and when the show aired some time later, '298' of this parish (in his much younger days) happened to be watching and (so he tells us) this is what inspired his interest in OHLE, eventually resulting in him joining our group.

[298]

Short story:

Around the same time it was Roy who suggested High Gill as a candidate to appears on a BBC TV kids programme called 'Corners' to answer some questions about how signalling worked. This duly happened, and when the show aired some time later, '298' of this parish (in his much younger days) happened to be watching and (so he tells us) this is what inspired his interest in OHLE, eventually resulting in him joining our group.

 

It's true...! I was home early from school after having to go to the Orthodontist to have a load of scaffolding wired into my gob. Something must have clicked enough to inspire my initial appreciation of modelled OHLE (having grown up with visits to Nuneaton Station and running down the garden holding a broom aloft to the washing line).

[talisman56]

No wires - 3rd rail, which will not be live - at my advancing age and deteriorating eyesight I'm not even going to comtemplate converting a Farish 4-Cep (N-gauge version) to work off the 3rd rail, even if only for lighting purposes. Ditto a Dapol '73/1' and a long-ago scratchbuilt 2-EPB.

[roythebus]

I recall coming along to Keen House to assist with some of the handbuilt headspans in the early days of OHLE construction on New Annington. At that time Jon Hewitt and Brian (can't recall his surname) were making a start on it, and I showed them how it had been done on 'High Gill' (and was being done on 'Carstairs'). That would have been about 1986 after High Gill had appeared at IMREX.

 

Short story:

Around the same time it was Roy who suggested High Gill as a candidate to appears on a BBC TV kids programme called 'Corners' to answer some questions about how signalling worked. This duly happened, and when the show aired some time later, '298' of this parish (in his much younger days) happened to be watching and (so he tells us) this is what inspired his interest in OHLE, eventually resulting in him joining our group.

Sorry I don't remember you Gordon, but in those days quite a few bods helped with various bits on NA. do you know what happened to John Hewitt, I'm trying to contact him having lost his address years ago. Brian Kirby of this parish was the other one.

 

At one stage there was an idea to use the NA layout for a BR signalling safety film, but nothing came of it. As an aside, the signalling was fully interlocked with the points with all the correct route indications; this was before the days of DCC, and all the switching was done with relays and light sensitive switches. It worked very well.

[Gordon H]

Sorry I don't remember you Gordon, but in those days quite a few bods helped with various bits on NA. do you know what happened to John Hewitt, I'm trying to contact him having lost his address years ago. Brian Kirby of this parish was the other one.

 

At one stage there was an idea to use the NA layout for a BR signalling safety film, but nothing came of it. As an aside, the signalling was fully interlocked with the points with all the correct route indications; this was before the days of DCC, and all the switching was done with relays and light sensitive switches. It worked very well.

I am fairly sure I saw John at a show fairly recently (i.e. in the last year or so) but am not sure which one it might have been.

I have certainly seen Brian Kirby a few times.

 

High Gill was also interlocked (as such), though the track layout complexity was nowhere near that of NA. I used a BBC Model B computer for our implementation, which is where it scored highly with the Beeb's programme producers, being used on one of their own shows in a practical way, not just for playing on-screen games.

[samkiller42]

I must say, the layout i'm currently planning (in my head) is to be OHLE/DCC powered, I'm a modern day person, so running steam or diesel isn't my thing, but as i'm looking to model French Electrics, i don't think i will have many issues, although, i do need to research it much further than i have done so far.

 

Sam

[Guest oldlugger]

I refer you to the comment I made earlier.

 

 

 

Cav

 

If you had read the thread at the very start, the observant personage would have noticed that I was responding to Xerces Fobe 2's statement; that is all.

 

Good day to you Sir

[RBE]

I did read it from the start and I was responding to you, with it being an open forum and all that, referring you to the reasons I feel theres no need to power them as you had asked. You have also previously replied to the quoted post of mine and yet you feel it necessary to quote me again. I simply feel that if there is nothing to gain by powering it then why do it? It visually makes no difference as I have the pan touching my wires and functionally makes no difference as I have dcc with lots of wheels running on a powered track.

Cav

[roythebus]

I am fairly sure I saw John at a show fairly recently (i.e. in the last year or so) but am not sure which one it might have been.

I have certainly seen Brian Kirby a few times.

 

High Gill was also interlocked (as such), though the track layout complexity was nowhere near that of NA. I used a BBC Model B computer for our implementation, which is where it scored highly with the Beeb's programme producers, being used on one of their own shows in a practical way, not just for playing on-screen games.

If you happen to see John around again, perhaps you can ask him to contact me via here. I lost his Glasgow address many years ago and have subsequently moved house.

[jamie92208]

You realise there's a catch: it means all track should be under the wire (at least those that have electrics running on them), including those difficult to reach hidden ones where the pans constantly de-wire

It was that problem that made me opt for dead OHLE on Green Ayre, If I made it live I'd have to ahve overhead on half the fiddle yard which would seriously muck up my crating system and even less of the layout would fit in the shed.   Fortunately I'll only have 2 emu's  and everything else will be steam hauled.

 

Jamie

[Multiple identity account 2]

The locos that you would have seen, and that are shown on Youtube are memory wire. I wasn't aware of the micro linear servos! Very useful. Servo decoders are available in the Zimo range, the MX632W looks like the perfect option so I will be revisiting some of my ACs very shortly.

http://www.youtube.com/watch?v=wqV7Q16DiSs

 

 

The bigger problem with trying to make working third rail pick ups for traction would be gaps, our stock simply cannot have the momentum needed to carry it over gaps in the juice rail, especially given how much we tend to cram pointwork into much tighter spaces than the real thing.

 

Andi

Any detailed description or a "How - to" for  assembling a working pantograph like that? I want one just to be raised and lowered not for current pick-up.

[298]

Here's an example of live overhead- I've never seen a working Grand Union Jn before:

 

[jamie92208]

Here's an example of live overhead- I've never seen a working Grand Union Jn before:

 

That's fabulous but I can guess why it's live overhead, just think of the number of relays to switch polarity on ll those 80 crossing frogs.  The relay matrix would be bigger than the layout.  Thanks for posting it.

 

Jamie

[GWC1]

The pan lifting can be done fairly easily with a standard servo - you just arrange it to pull on a spring which is connected to the pan. When slack the pan drops under gravity. When pulled the spring raises the pan but it can still be pressed down by the wire by stretching the spring.

On the 76 it is pulling two servos up and the tiny servos I originally used (shown here) have had to be replaced by more powerful TowerPro30 servos.

 

On the subject of using the OLE as common return, that is what we do on Deepcar and Carstairs. It gives better pickup as there are another couple of contact points (on a 76 - only 1 on an AC loco of course). We originally tried the idea of having electrics working between OLE and track feed rail and diesels between track feed rail and track CR rail, but got weird cross feed effects if we had more than one of each type of loco on the layout, regardless of where they were. If you have a diesel and an electric in each of two sections with one section turned on to a controller and try to move, say, the electric, you also apply that same voltage to the other 3 locos in series, even if their section is off. That caused us to abandon that feeding idea.

[jamie92208]

As I haven't posted for a while I thought I would share this.  I took part of Lancaster Green Ayre to Nottingham.  The first section of overhead was up and the quetion I was asked most often was

"Is the overhead live".

 

Jamie