I can't speak for present-day U.S. practice, but I encountered several transfer tables at streetcar barns in several different Japanese cities in the 50's and 60's. When there was no space for a throat built of turnouts (even using usual streetcar radii) the transfer table made it possible to have a car barn 8 tracks wide where the longitudinal space would have allowed only three. What made those streetcar transfer tables different was the presence of overhead wire, since cars moved on and off the table under their own power.
In one of his long-ago track plans, John Armstrong crammed an O-scale engine terminal and shops onto a 4 x 8 table. In the accompanying text, he noted that the transfer table had to handle the longest locomotive (less tender,) plus the 0-4-0T yard goat. If the same transfer table served a car repair facility that maintained long rolling stock (up to 3-truck articulated tavern-lounge cars!) the table length had to be adjusted accordingly.
On a Class I railroad, transfer tables wouldn't be found at every division point. Only major shops (of which even the biggest roads had one, or maybe two) would need them and have them.
Golden, CO, has a rather unique transfer table operation. Under cover at the Coors shipping facility, there are a string of two-track transfer tables, each long enough to handle a 60 foot refrigerator car. Normally the dockside track has a car on it, being loaded, while the other track is aligned for use as a thoroughfare. When a car is loaded, the table moves the car to the 'thoroughfare' alignment and a switcher retrieves it and replaces it with an empty, which is then moved sideways to dockside. All of the other cars continue the loading process undisturbed.
There is one very practical use for multi-track transfer tables on model railroads. They're great for hidden staging!
Chuck (who had, and will have again, transfer tables for down staging at Minamijima.)
You may notice that almost all transfer tables are in workshops. There are two reasons for this:-
1. for live locos it is quicker and easier for them to roll through switches to get where they are going... and they won't fall in the pit! If they need to be turned a transfer table is no use. Most sheds useing a a turntable try to provide an alternate route round the table into the shed so that if the table needs maintenance they can still use the shed.
2. a table seems to be more of a maintenance issue than a turntable and almost always needs to be powered... which means someone to keep it ready for use before bigger electric motors.
I think that the reason that workshops use them is that they can get everything into much less space which saves money on land, buildings and heat at least. Locos - or whatever - stand around much more in workshops rather than wanting to go in an out frquently.
In modelling multi-track transfer tables, sector plates and limited range turntables have long been very popular in the UK. They can mean that you need few or no switches. They give access to a number of roads in very short space. A few I've seen have been double ended... the dead end giving access to a turntable on a fixed board... this is great for steamers.
(A sector plate is the same as a turntable but the pivot is under one end so that the plate swings in an arc. A limited turntable is exactly the same as an ordinary TT with the pivot in the centre but it is restricted to only swing a number of tracks - the tracks are on the table - either side of centre. A few layouts actually use a full, multi track TT... when all the trains have arrived from one direction they swing the whole lot round and they are all ready to go back the other way... naturally this requires quite a lot of clearance, the bearing needs to be strong enough to take the weight and it all has to be kept balanced)
Jetrock..Ive heard that the Sacramento back shops are to be torn down for a sports complex..How does one get in there to take pictures, work there a numberof years....John
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jwar wrote: Jetrock..Ive heard that the Sacramento back shops are to be torn down for a sports complex..How does one get in there to take pictures, work there a numberof years....John .
Not entirely correct: most of the Sacramento shops buildings that are still standing will be part of the Railroad Museum within a decade or so. The open areas that used to be the rest of the yards and shop complex are going to be developed into new neighborhoods, possibly including a sports complex. The shops buildings that do not become part of the Railroad Museum will be adaptively reused, possibly into a public market or something.
http://www.cityofsacramento.org/dsd/current-projects/railyards/
So no, they aren't going to tear down the remaining shops buildings. Getting in there is fairly difficult unless you are interested in becoming a Railroad Museum docent--there is a Maintenance of Way crew that works there regularly, maintianing exhibits and equipment, and keeping the Sacramento Southern running. If you worked there and might be interested in helping out, they could probably use your help! Check the CSRM website (http://www.csrmf.org) to find out how to volunteer.
Here's the one that's in Beech Grove (Indianapolis), Indiana, at the Amtrack repair facility.
http://local.live.com/default.aspx?v=2&cp=qmkrv67tt71y&style=o&lvl=1&scene=2552912
And if you want to see one in operation on a model railroad here it is ....
Jerry SP FOREVER http://photobucket.com/albums/f317/GAPPLEG/