4-8-4 - 4500 Class Driver Wheels And Driving Rods Measurements - Blue Print, Drawing, Plan - Inquiry

Hello Frisco historical society -

I was wondering if anyone had any measurements of the legendary 4-8-4 4500 class driver wheels and driving rods.

Specifically in relation to the driver wheels and driving rods width measurements.

Any help would be greatly appreciated.

Thanks

AJ

 

Why do not you have a look at the scale drawing of the 4-8-4 SLSF 4500 class posted by Ken W. (Meteor910) and take some measurements?

That is now in the "Steam Locomotive Diagrams" thread instead of the "4-8-4 Northern" section.

Tom

 

There are several transverse dimensions that can be gleaned from the locomotive diagram.

From the diagram, this should give you a start.

Cylinder centers: 7'-10"
Valve centers: 8'-11"
Frame center: 3'-4"
Width over cab: 10'-6"
Width over running boards: 10'-10"
Width over steam chest: 10'-11.5"

The diameters of the boiler courses are also listed.

85-11/16"
91-25/62"
100"

For more detail information, I would recommend a road trip to Springfield, MO.

Pay a visit to the 4-8-4 SLSF 4524 at the Railroad Historical Museum, Grant Beach Park, 1300 North Grant Avenue, Springfield, MO 65802.

http://rrhistoricalmuseum.zoomshare.com/0.html

Call one of the numbers listed on the web site, and make arrangements for a visit.

The caretakers are mostly Frisco guys, and they are most gracious people who are happy to talk about the Frisco and the 4-8-4 SLSF 4524.

Several years back, I spent most of a Saturday afternoon talking with Al Weaver, who was an engineer for the Frisco.

Take your tape measure, note pad, and camera.

Leave them a nice donation after you are done.

 

Hi All,

It has always been my understanding the outside diameter figure was the wheel diameter including the tire but not including the flange.

Basically the distance from the top of the rail to the top of the tire on the outside edge.

The inner diameter was the diameter of the inner wheel less the tire.

Since the outside diameter figure was used in several steaming calculations it would not make sense to include the flange in the outer diameter measurement.

Please correct me if I am wrong.

I make no claims to being an expert, just a compiler of data.

One of the biggest problems I sometimes run into doing research on steam locos is the outside diameter.

Particularly on second hand locos, these figures are often just measurements taken at the point in time it came on the road.

Records in SI&E, GC&L and BR&L are usually figures they posted with the locomotive record when they purchased it.

A 3" thick tire with one inch of wear changes an outside diameter of for example a 60" wheel to 58" outside diameter.

Typically most diagrams show the figure with new tires.

Some roads changed tire thicknesses often trying to find optimum operating dimensions and calculating in wear.

The Chicago and Eastern Illinois (C&EI) was notorious for that from my research.

If I am incorrect please let me know.

Allen