Steam & Excursion > Name of wedge device used on short turntables

Hello all,

I'd like some help finding information on the wedge devices that were used to elevate the rear axles of tenders so locomotives could be turned on short turntables.  These devices were essentially twin ramps that were placed on rails at the far end of a turntable.  The locomotive was then backed onto the TT and the wedges elevated the rear tender wheels so they cleared the rails.  Several of us have looked in various publications but have not been able to find an official name for those devices, or drawings of them.

In various publications, they have been referred to as "wedges", "turntable skates", and "outriggers"; the process was referred to as "jacking" by a UP employee who worked with them in the early 1950s.  Among other things I'm wondering if these devices were manufactured and widely used in those days or if they were custom made in company shops and possibly a unique design on each RR.

Any help is appreciated.

Thanks,

Mark 

As I understand the challenge, the devices only worked on certain 
locomotive tenders.

Specifically, only on modern tender with cast, one-piece tender frames.
Sometimes called 'pedestal renders', also known as 'centipede' tenders.

Typically, the major portion of the tender was carried on 5 wheel-axle sets, with a 4-wheel 
guiding truck, at the front of the tender.   The rear two axles could be run up on the ramps ,
until the elevated wheels, and their flanges, cleared the approach tracks at the turntable rim.

It was necessary that rails were positioned exactly 180 deg. from the lead track of the approaching
locomotive.  To install the ramps, the loco's front wheels would be run clear across the turntable,
and out onto the matching 'over-run' rails that lined up with the TT and It's central pivot .

The temporary 'jacking-rails' would be placed, and the engine gingerly backed onto the. ramps, 
until the pilot wheels at the front were clear to allow the TT to freely spin.

This solution was intended purely as a compromise and the practice was a relatively rare event.
And only certain classes of locos required the device.

Engines & tenders. with conventional trucks are designed to be vertically flexible to
accommodate uneven tracks through curvees , and uneven, undulating rails to keep
the wheels all sharing the load, over uneven tracks.  Thus, the improvised wedges
would simply be accommodated by the compressible springs ...keeping all,the wheels 
sharing the he load. This applies to four wheel trucks, 6-wheel trucks, or eight wheeled trucks.

With the centipede tenders, the 5 axles are carried in one frame.... as the whole frame is
raised, the rear-most axles drop onto the 'binders' that tie the pedestal jaws together,
to confine the axle boxes.

​W.


 

They were shop made by the railroad to cover a temporary problem. Railroads usually made the sure the infrastructure would handle the locomotives they intended to use. In the case below, the use of the locomotives was temporary with a quick, cheap solution.

Examples of use by PRR:

http://www.columbusrailroads.com/prr%20santa%20fe.htm

http://rypn.org/forums/viewtopic.php?f=1&t=29063&start=30

I remember that the UP North Platte roundhouse had one of those turntable bridge "extenders", in case a 4000 class locomotive mistakenly was run east of Cheyenne. When I was there in Late 1963, a 3700 series Challenger was in the roundhouse, set-up for blowing the snow out of switches in the yard. The MofW department had control of the locomotive, and had a good sized steam pipe, with a lot of holes drilled in it, mounted under the pilot. I remember that they used it once when I was there with the EMD GP35-DD35-DD35-GP35 Demonstrator set. Apparently they were not able to properly control the steam supply to that pipe, as it tended to blow much more than snow out of switches, like ballast, tie plates & spikes! At any rate, I inquired about that turntable bridge extension "contraption", over in one corner, as was informed that they no longer needed, nor used it, as the 4-6-6-4 fit OK on the turntable.

Bottom line,,,,,,,,I never did find out what the proper name was for that "contraption" was. Maybe it would be in the UP historical records at the UPHS.

C&O did the same with the H-8 2-6-6-6 locomotives at one or more locations, as I understood.   

> Bottom line,,,,,,,,I never did find out what the proper name was for that "contraption" was. Maybe it would be in the UP historical records at the UPHS.

Thanks for the comments.  We've discovered that the device was used at North Platte through the 1940s until late 1950 when they got a longer 126 foot turntable capable of handling the 3900 class Challengers.  Other UP terminals used them occasionally also.  We are checking drawings and other records to see if something turns up, but nothing so far.  

By the way, do you recall what the thing looked like?  Was it a pair of steel "ramps" with rods or bars between them to keep them vertical, aligned & maintain gauge, or, maybe two separate "ramps" that were shaped so they were supported on the ties like a rerailing frog?

Take care,

Mark

" SKATES" is the term I heard for the C&O version, a long time ago, but that may have been a "railfan" term and not an official "railroad" term.  

UP used the wedges to raise the rear wheels of the tender for locomotives that were too long for the turntable. 
They wouid run the wheel up on the wedge and then use an iron bar to shove in the Journal box support to hold that wheel up in the air. 
They would repeat for as many wheels as they needed until the whole locomotive was on the turntable, hanging off in back.
Turn the locomotive and reverse the process to get it back on the rails.

Bob Krieger
Cheyenne, WY



Edited 1 time(s). Last edit at 07/03/20 05:24 by Bob3985.

Does this help?

-LD

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LarryDoyle Wrote:
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> Does this help?
>
> -LD

It does indeed help. Its worth at least a thousand words.
ALLEN

One obvious difference in these discussions was that the UP tenders in question were rigid frame centipede and the ATSF 2-10-4 and C&O Allegheny tenders were both 8 wheel Buckeye trucks. Buckeye trucks were not rigid frame. Buckeyes obviously worked on the PRR Columbus turntable. Centipede or pedestal types would be a different situation.

Posted from Android

> Does this help?

Thanks for the photo, haven't seen that one before.  Do we know where and when it was taken?

Take care,

Mark

mamfahr Wrote:
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> > Does this help?
>
> Thanks for the photo, haven't seen that one
> before.  Do we know where and when it was taken?
>
Sorry, I don't.

-LD