Turntables - a variation on a theme...

[Kozzie]

QUOTE: Originally posted by M636C

Dave,

I've found a photo of a much bigger turntable on the Santa Fe that had a huge truss girder (looking like a bridge) supporting the track. It was in a pit, but a relatively shallow one. It was one of the last depots opeating steam and could turn the 5010 class 2-10-4s with their eight axle tenders. I've forgotten the name of the location right now, so i"ll post it later. But the principle was used in the USA.

Peter

Peter - thanks for the interesting detail, looks like there's quite a few variations on this turntable theme. [:)]

[M636C]

Dave,

I've found a photo of a much bigger turntable on the Santa Fe that had a huge truss girder (looking like a bridge) supporting the track. It was in a pit, but a relatively shallow one. It was one of the last depots opeating steam and could turn the 5010 class 2-10-4s with their eight axle tenders. I've forgotten the name of the location right now, so i"ll post it later. But the principle was used in the USA.

Peter

[Kozzie]

QUOTE: Originally posted by jchnhtfd

Dave -- there is a prototype for everything, or so I've been told... but I do wonder, in this case (I know the model turntable to which you refer) if the reference to Swiss design wasn't to the design of the model and its drive and support and locating mechanism, rather than to the prototype -- if any -- for the turntable. If it's the one I'm thinking of, it's pretty durn thin to be a model of the real thing...
On turntables with catenary, the catenary can be strung on the turntable. There are several ways to power it, but the simplest is to use a wire to a central tower.with a pivot (slip ring)

Jamie, that's an interesting point - a Swiss design. I did have a good think about the conversation I had with the shopkeeper, and I'm fairly certain he said that the prototype was used in Switzerland. Maybe not widespread though.

However, it wasn't a large diameter turntable. Only 11 inches - not sure what that is in scale feet. Probably for turning small steamers....

It would be handy in a layout that doesn't have room for a larger, pit style turntable, and only runs smaller model locos....

Dave

[jchnhtfd]

Dave -- there is a prototype for everything, or so I've been told... but I do wonder, in this case (I know the model turntable to which you refer) if the reference to Swiss design wasn't to the design of the model and its drive and support and locating mechanism, rather than to the prototype -- if any -- for the turntable. If it's the one I'm thinking of, it's pretty durn thin to be a model of the real thing...
On turntables with catenary, the catenary can be strung on the turntable. There are several ways to power it, but the simplest is to use a wire to a central tower.with a pivot (slip ring)

[Kozzie]

Peter - it was certainly a turntable with no pit. The shopkeeper was pretty certain of that -part of the attraction for some modellers, no need to set it into the layout, just build up a track leading to it.

Apparently not a large turntable prototypically, one would only use it for smaller locos such as smaller steamers.

I remember that the support girders were not visible - a small wall encircled the outer edge...

Dave

p.s. Peter, your next will be a personal landmark! heh heh...

[M636C]

I don't recall seeing any turntables of that type in Switzerland, and I doubt that they would be common there. I'll have to check any photos and books, but the only thing that comes to mind about turntables in Switzerland is that they had overhead wires for the electric locomotives (fixed, if I recall correctly). I hope they dropped the pantographs when turning!

What you are describing is a turntable with the support girders above the decks, and either no pit or a shallow pit. The turntables I described were conventional turntables, with the girders below deck, but located above ground.

I'm sure I've seen your version, but I'll have to think about it. Maybe someone else can help.

Peter

[Kozzie]

QUOTE: Originally posted by M636C

Dave,

There is a raised turntable at the locomotive depot in Forrestfield, Western Australia, which is more than two metres above ground level. Whether this is related to that part of WA being made from white beach sand, and a turntable thus would require a complete concete pit, I can't say. (We don't call them Sandgropers for nothing!).

It sounds as though you haven't studied rail history in Brisbane, Queensland, either! There was a turntable there, adjacent to the Fiveways road (and rail and tramway) junction that was built on a wooden trestle. The wasn't a walkway around it, so the turntable was driven by an air motor powered from the locomotive air reservior. the trestle was about four metres high, and projected out from an area on an earth embankment. I guess it was an afterthought.

There is a picture in a book "Destination South Brisbane" published about the time of building of the bridge linking the North and South sides of the Brisbane system.

(This wasn't another question just for me, was it?)

Peter

Peter, this one was for you and whoever else would like to throw a comment in.

You're right, I didn't know about that raised turntable in Brisbane. However, wouldn't they have been less common then the "excavated" type in Oz? There seems to be heaps of pictures of that type both here and overseas.

The HO turntable I saw in the shop was made by Peco and apparently it was a Swiss design. I was primarily wondering if that was a dominant design of turntables in Switzerland or anywhere else...

[M636C]

Dave,

There is a raised turntable at the locomotive depot in Forrestfield, Western Australia, which is more than two metres above ground level. Whether this is related to that part of WA being made from white beach sand, and a turntable thus would require a complete concete pit, I can't say. (We don't call them Sandgropers for nothing!).

It sounds as though you haven't studied rail history in Brisbane, Queensland, either! There was a turntable there, adjacent to the Fiveways road (and rail and tramway) junction that was built on a wooden trestle. The wasn't a walkway around it, so the turntable was driven by an air motor powered from the locomotive air reservior. the trestle was about four metres high, and projected out from an area on an earth embankment. I guess it was an afterthought.

There is a picture in a book "Destination South Brisbane" published about the time of building of the bridge linking the North and South sides of the Brisbane system.

(This wasn't another question just for me, was it?)

Peter

[Kozzie]

All of the turntables that I've seen pictures of downunder are set into the ground to allow the track that leads to it to remain level. That's also what I've seen in pictures form the U.K. and the U.S.

Here's the variation: [;)]
In my local MR store they had a HO scale turntable that didn't need setting into the layout base. It looked like a circular platform slightly raised above the surrounding ground. So the track feeding to it needed to be elevated slightly.

The shopkeeper said it was a Swiss design and apparently reasonably common over there. It would save on the excavation work I guess.....

Has anyone else seen these? Especially in the "12 inches to the foot" scale...?

Dave [:)]