Passing Siding Question

There might have been an obstruction there when the track was laid. Maybe a signal. Then the signal was (re)moved and the track not realigned.

Yes, that sounds probable. Some sort of obstacle (signal, drainage, etc.) was located there and it couldn't be moved until after the siding was installed.

__________ Mark Mathu The Green Bay Route:

"I started out with nothing and I still have most of it."

I thought about the track "going around" a signal but that doesn't make much sense as there doesn't look to be room for signal AND siding clearance.

As a side note, I have seen this sort of thing almost everywhere BN(SF) runs in my local ( Portland, Seattle, Spokane, and now in Libby. Not all sidings are this way. My guess would be 60ish percent have the extra jog. West Kootenai does, East Kootenai does not. I will look at Troy again, but I think both ends do not.

BNSF track guy?

You can almost always bet that anything done on trackage is driven by cost. The moved signal idea is plausible, but I wonder if it could be a relic from steam days.

If the main was heavily used, there might have been a water tank or standpipe at the head end of the passing track. That way, the waiting westbound (freight) could top off water before or after hitting a grade. That would save time and free up the main faster. It would also be important to lubricate before and after a heavy pull, and for safety the siding might want to be a little further from the main near the engine, in case an engineer oiling got caught trackside and had to hug a driver to keep from being mutilated by a passing train. Once something like this was in place, there would be little reason to remove it, since it would only save a couple yards of track, and realignment would be costly in labor. If I am right, there should be other sidings like this, with most of the jogs on the uphill ends.

There could be other reasons, like a lead to a spur that was removed, or an area designated for unloading and loading a car that was a little further from the main. My guess is the answer might be waiting for you in old photos at a local historical society.

I will hazard a guess that it might have something to do with the frog-angle of the turnout. Constructing the ends of the siding the way shown in the photo gives a smaller degree of curvature when transitioning from curved to tangent track on the diverging route. The smaller the degree of curvature ( larger radius ) the easier long cars and three-axle trucks on locomotives can negotiate it. Even one degree of curvature can have an impact on train movement. In the 30's,

40's and 50's, the Milwaukee Road, the fastest steam road in the world, had one degree curves superelevated and speed-restricted to 100 MPH. CSX recently re-laid rails through my town. the new stuff is 140-something pound. ISTR 144, but it might be 148, or something around that. Anyway, it's all brand new with clean, white ballast, perfectly edged - - -very unprototypical.

Froggy,

--------------------------------------------------------------------------------------------------------------------- Thanks for the laughs, Mark! You brightened my day!

Bill Bill's Railroad Empire N Scale Model Railroad:

History of N Scale: Railroad Bookstore: to 1,100 sites:

On Sun, 11 Jun 2006 15:57:34 GMT, I said, "Pick a card, any card" and Froggy @ thepond..com instead replied:

I'm sure this is correct as longer cars and powered components might do heavy damage to the frog unless they were well past the turnout area as they began to conform to the new radius. Forcing a long conveyance to turn both right and left while traveling at speed would put some incredible stress on the turnout.

-- Ray

Wouldn't that mean both ends of the siding would have the offset? That didn't seem to be case - "Not all sidings are this way. My guess would be 60ish percent have the extra jog. " Note that he said "extra jog" (singular).

I can't answer that. I don't have enough insider information from the ROW department that builds track out there. I just offered an opinion on the one cited example. The civils who engineered the thing have the correct answer, we are all just guessing. It costs a great deal of money to do a grade re-alignment. It is not done for appearances. if there is no pressing need to do the other end, it most certainly will not get done.

Froggy,

Chalk up another guess for an old signal that was removed. Until

1985 (I think that's the date...it was mentioned in that new MR layout details issue), that left hand signals weren't used until after 1985, and that one has a left hand signal. I know the ex-Pere Marquette in Michigan has one end of most of the sidings with a jog like that, for the signal, although it would be the other end (the mainline signal is the one being jogged around...the sidings signals were dwarf signals)

I don't think so.

Froggy,

I don't follow... I wasn't trying to be humorous on my reply.

You may want to post the question on this forum (put BNSF in the title):

Wyhogg (AKA Al Krug, a BNSF engineer) will probably know the answer.

Daniel Lang

------------------------------------------------------------------------------------------------------- I read poor planning in your reply, Mark. > No matter, I got a lot of good laughs thinking about it. I can see it now--the worker says, "Shouldn't we remove that old, unused obstacle before we install the siding, Boss?" "NO! We'll put the siding in and then remove the obstacle!"

Bill Bill's Railroad Empire

Thanks Daniel, will re-post here when I get an answer!

todh

Went to

which is the 12" to a 1' scale and asked my question.

One of the railroad engineers answered. Check out the forum's topic ( Passing Siding Question ). Just to let you know, there were many more folks checking out the pix from the infopop group than this group. You may be interested in creating an account and asking your prototype questions there also.

todh

On 12 Jun 2006 10:36:36 -0700, I said, "Pick a card, any card" and "ctclibby" instead replied:

Frank Maguire, who also answered there, is correct. There's no need to put a signal between tracks. It's all about long conveyances, tangential angles and stresses on both track and car when they have to rapidly change their direction of travel.

-- Ray