I am having some difficulty in finding information and photos of Drop Pits or Tables in steam-era roundhouses. These tables were used to remove drivers and trucks from locomotives and tenders so that the they could be transported to a machine shop (usually annexed to the roundhouse) for repair. (They are not the same as the inspection pits usually found under each roundhouse track.)
Can anyone help point me toward books or other sources where such information might be given? I am interested in how exactly the tables worked. Any information or suggestions would be greatly appreciated.
Rarely would you find a drop table in a steam era round house. Drop tables were usually in the back shop, driver tires were changed in most roundhouses with out the use of a drop table. Most steam era drop tables are used today, they came in a variety of sizes. The shorter ones are handy for changing out traction motor wheel combo’s with out dropping an entire truck. For truck changes a long droptable is used , or the whole locomotive was jacked.
Randy
Talking about jacking a whole locomotive, how about jacking an entire train?
The French TGV is articulated, and as a high-speed train, there is frequent wheel maintenance (maintaining wheel profiles). They have a facility where they can jack an entire trainset as a unit without taking it apart.
Often would you find a drop table in a steam locomotive roundhouse. While tires could often be changed and contoured while on the engine, journals could not, and some means had to be provided for getting the wheels (drivers and trucks) out from under the engine so that they could be taken to a machine shop for journal work. N&W had them at most major engine terminals, and I’m sure other railroads did, too.
I don’t know how many actually had drop tables, but the Roundhouse at Northern Maine Jct. (Hermon, ME) on the BAR had one. Must’ve been quite impressive in its day.
Probably very few roundhouses outside major terminals would have needed them. If a locomotive showed up at an outlying point with a really bad journal, it was possible to run the affected driver up on a wedge and block the equalizers to take the weight off the axle, and run it to a major terminal at low speed without a train.
I think one had been installed in my home town roundhouse which was an outlying point, but Heaven help the guys if they ever had to try to use it . . .
The Brooklin roundhouse in Portland, Or. has a short drop table large enough for diesel/car wheels.
It sits in a pit that runs perpendicular to the track it services. The pit is about 12 feet deep and 5 feet across. About 6 feet below floor level is a set of rails running the length of the pit. A four wheeled trolley rides these rails to carry a wheel set with the table lowered to a set of rails at floor level between stall tracks that lead out the back of the roundhouse. The table can then be raised to floor level to onload the wheels to this track.
The trolley has a large hydraulic cylinder the same as you would see in an older auto shop with a below the ground car lift. The cylinder is raised and lowered with water, with a set of valves and a small pump nearby. The trolley is shuttled back and forth with an air powered come along and a cable.
The table itself sits at the top of the hydraulic cylinder with two short sections of rail bridging the gap across the pit. When the table is fully raised, a lever moves locking pins into notches in the pit walls to allow the table to bear weight.
I have heard in the past that Albina yard also had or has a drop table, and that it was or is large enough for steam locomotive drivers, but cannot say any more than that.