Reviewing photos and designs on line of large prototype deep pit (circa 8 ft?) turntable installations I don't find obvious provisions for maintenance workers to readily access the turntable pit bottom or sides to service the drive motors, gears, gear rack, table bearings and such, or to clear out storm debris and other foreign objects. Some photos show ladders extending down from the deck. A photo of the Strasburg installation circa 1926 appears to show an opening in the pit wall with a plate cover above - possibly a stair or ladder well?
Any information on the topic appreciated.
Isambard
Grizzly Northern history, Tales from the Grizzly and news on line at isambard5935.blogspot.com
The turntable I'm familiar with at the B&O's W. 3rd St. Roundhouse in Cleveland, had all the mechanical drive works on the outside opposite corners of the bridge. There was no reason to routinely get "inside" the bridge but there was an access plate at the center, between the rails, to get to the inside for inspection of the center bearing and bridge structure.
Toward the end of B&O's use of the roundhouse, there was no second trick crew on duty and if snow was predicted they would leave the turntable running at its slowest speed from 4 PM to midnight in order to keep the bridge from getting snowed in.
Well, one night they had a LOT more snow than they expected and the bridge got jammed-up. The controller overheated and burned down the operators cab!
It had a streetcar type reverser/speed controller for the motor (I can't remember if there was one or two motors, I believe it was one). A new cab was made out of plywood but no where near as nice as the original.
The pit generally collected lots of litter but the bridge rode about 8" above the bottom so only the big stuff got cleaned out. No real need for a permanent ladder since one could be found in the roundhouse only fifty feet away.
Ed
Two things come to mind. First, there's usually no need for routine maintenance frequent enough to require a fixed ladder, at least by the industrial safety standards of the day. And there's always ladders around.
The other is that ladders tend to snag on the rotating TT bridge. There's very little clearance when it turns. I'v seen ladders made out of slender bars fixed on pit walls in other situations. If arranged carefully, they might clear the bridge as it comes around.
Mike Lehman
Urbana, IL
Most of my prototype's turntables had very shallow pits, with the ring rail only about a foot below rim level and only about a foot step down to the floor from the spaces between the ring rail ties. No need for a ladder. The turntable design was a tapered throuth girder.
The exception was a very deep concrete cistern, a detention structure for the yard drains so they wouldn't overload the local wastewater system. The turntable was a deep deck girder and the center bearing was on top of a concrete pillar. As I recall, that one had a ladder from the surface to the ring rail set in a niche in the upper wall, rather like the cistern ladder of a NYC 4-10 pedestal tender. From the ring rail down there was a ladder rather like the grabiron ladders on older wood box cars. In that one case, there were no nearby structures where adequate ladders might be stored. There was no engine house, no coaling facility and the water standpipes were a considerable distance away, located for the convenience of through freight power rather than the local switching crew.
Chuck (Modeling Central Japan in September, 1964)
Y'know, Isambard, I never gave it much thought, except maybe to remove snow from the pit, here in our northern climes. I just firgured they plunked a ladder down against the pit wall onto the base of the ring rail and had at it. I think somehwere along the line, I saw a photo of a turntable with a ladder permanently attached near the end of the it. However, I was pleasantly surprised when I opened the long awaited Carstens book, "Locomotive Terminals & Railroad Structures and saw, on Page 11, photos of two different TTs, one a through girder and the other a deck girder, each with a square opening in the pit wall, covered with a trapdoor. These look to be steel plates, but could just as easily be of board construction, just as long as nobody could fall through. Both turntables were powered (the through girder's power arch is shown, but the other's doesn't show in the photo, though it had an operator's shelter).
Although Walter C. Berg, C.E., in his 1893 tome, "Buildings & Structures of American Railroads" does talk about turntable pit drainage (he was very thorough, even talking about the cost per hour of operating various facilities--often in cents!), he didn't say much about TTs and pits. BTW, if any of you want to simulate a powered turntable and doesn't want to install a power arch, I visited a site in the Upper Penninsula of MI where they were using the TT as a bridge to get into a sort of warehouse (used to be an engine house). Its power came through a conduit pipe sticking out of the pit wall, leading to the center support pedistal, where the power came through commutators. A control box like that of a trolley or interurban car was mounted on what was left of the pipe railing along one side!
Deano
NP 2626 "Northern Pacific, really terrific"
Northern Pacific Railway Historical Association: http://www.nprha.org/
I am a volunteer at the Steam Railroading Institute in Owosso, MI. The Institute's turntable has a ladder down the side of the bridge at the arch. The pit is fairly deep - ring rail is maybe 6 to 7 feet down from the lip. The center is maybe 9 or 10 feet deep. The TT was originally from the Pere Marquette in New Buffalo, MI.
The Institute owns and operates the Pere Marquette 1225 Berkshire. A good cure for fear of heights is getting on top of the boiler when the locomotive is on the turntable. It's a loooong way to the bottom!
George V.
Turntables are old, pre-OSHA contraptions. I am putting in another one, and I think I will simply add a ladder lying on the ground next to the pit wall. Thanks for the heads-up on that.
It takes an iron man to play with a toy iron horse.
A ladder lying on the ground is a big-time tripping hazard. I suppose there are railroads that would have tolerated this in the past, but certainly not today. Lean that ladder up against a building, or put it on some sort of rack.
tom