Early Passenger Trucks info wanted

[FLSTEAM]

I would like to try my hand at building some early swing link passenger car trucks.
I don't under stand the connections of the leaf springs to the bolster. The coil springs are not a problem.

Does anyone have drawings that show the bolster detail ?

John B.

[ccvstmr]

Hello John,

Here's some pix and explanation that might help you.

From a top view...there's 2 cross members that span the side frames. The space in between is for the swinging bolster.

The (8) nuts you see in pairs support the ends of long "U" bolts for the swing link supports.

Underneath (and to answer your original question)...the elliptical spring castings fit a notch in the wooden bolster on the top side and screwed from the top down (flat head screws visible in the 1st pix). On the bottom, the cast springs fit into notches in the spring plank on the bottom and are also screwed. The spring pins visible at the top of the swing links...go thru the suspended "U" bolts.

Had a discussion here on Chaski sometime last year about upward inclined inward, or upward inclined outward, swing links. While I have seen both versions AND parallel swing links, I believe the best orientation is the upward inclined inward. Using the above photo for reference, as the car enters a left-hand curve (for example), the car body is more likely to lean to the right. With the upward inclined inward swing links, the right side of the bolster will be raised while the left side will drop down. In effect, making the car lean "into" the curve. Upward inclined outward swing links will have the opposite reaction. Parallel swing links will simply raise the car body parallel to the track.

Does that help explain the swing bolster configuration and assembly question? Carl B.

[SZuiderveen]

John B.

Here is a cross section. I can get more from this series of figures, if you need.

The rectangular spring bands on the elliptical springs fit into shallow rectangular sockets in a pair of flat castings, one attached to the bottom of the bolster ("swing beam") and one attached to the spring plank.

Steve

[FLSTEAM]

So, If you pick up the truck with the swing link the weight of the truck is supported by the leaf springs?

JB

[Dick_Morris]

The Voss book "Railway Car Constructioin" (https://books.google.com/books/about/Ra ... M1AQAAMAAJ )and the early Carbuilder's Dictionaries (1879 and 1888 are a couple) have full sets of drawings of passenger trucks, including all the individual pieces. Both are available on the Internet. I'd start with archive.org for the Carbuilder's Dictionaries .

[SZuiderveen]

So, If you pick up the truck with the swing link the weight of the truck is supported by the leaf springs?

JB

The leaf springs support the bolster and the carbody. The equalizer springs support the truck frame, which support the swing hangers, which support the spring plank, which support the leaf springs. The axles, journal boxes, and equalizers are unsprung weight.

Steve

[FLSTEAM]

Steve I think I understand all the connections. My real question was in the case of derailment and I need to pick up the car body, the leaf springs are connected top and bottom. Is there some ridged attachment or some floating connection?

Thanks BTW

JB

[SZuiderveen]

Steve I think I understand all the connections. My real question was in the case of derailment and I need to pick up the car body, the leaf springs are connected top and bottom. Is there some ridged attachment or some floating connection?

Thanks BTW

JB

John,

The truck has a pair of keeper straps that span the two inner transoms over the bolster. See circled item on drawings. These straps are not on the truck Carl posted photos of. If these straps are in place and you have a bolt for a center pin, you can pick the whole thing up without it disassembling. Newer trucks had an extension on the bolster that went under the frame that would keep the springs in place when unloaded. Harder to replace springs on, I know it, I have done it on the full-size!

Steve

[FLSTEAM]

I see said the blind man. I just had an Ah Ha moment.

JB

[Loco112]

John, are you wanting to build: 3' gauge, 26" wheels, 4" x 7" journals?

[FLSTEAM]

John, are you wanting to build: 3' gauge, 26" wheels, 4" x 7" journals?

That looks it would fit the bill. John B

[Glenn Brooks]

Just saw a similar spring arrangement and truck style this past weekend, in service, on the Napa Valley Railroad. The cars were originally built for the Northern Pacific RR as first class Pullmans in 1914. One pedestal has a casting date of 1894. The pedestal and truck next to it is stamped "Amtrack"! Definitely old and new. A retired BN engineer looked at these this morning and said these old Pullman trucks and cars originally were certified for 90 MPH mainline service.

Here's some pics of the spring arrangement.

Finally, here's an alternative. Notice the coil springs on this baby. Serious stuff.

Glenn