Tank Plant

(Note: This is an early print release version and will be subject to change and revision by the author as needed – sort of a “Beta” version of the book)

Every single modeler of US armored vehicles knows his “Shermanology” by heart: the M4 and M4A1 were powered by air cooled engines, M4A2s by diesels, M4A4s were the “long hull” tanks with the Chrysler A57 cluster engine, M4A3s were powered by Ford V-8s, and the M4A1s were the only ones with cast hulls. But outside of a handful of serious researchers like Steve Zaloga, Joe Demarco and Kurt Laughlin few know WHERE they came from or how they came to be.

Many of the cast components such as the one-piece transmission covers, the turrets and the hulls of the M4A1 came from major steel foundries that had a lot of experience with casting large unwieldy objects, the primary ones of which were one-piece frames for steam locomotives. During World War I the railways in the US were taken over by the United States Railway Administration (USRA) who designed many standardized locomotives for all railroads to use. During this period they refined their casting techniques and could cast massive locomotive frames in one piece with even the cylinders and steam chests already in place, an innovation possible in few other nations even during World War II.

As such, when the US began to spool up its industries for World War II, the first place they turned was to the foundries with this experience in the United States. (So did the Russians, which is why their first tanks came out of the Kharkov Steam Locomotive Factory in the Ukraine.) Tanks require three kinds of steel: rolled steel (e.g. homogenous armor), face hardened (non-homogenous armor) steel, and cast steel. The first two are superior metallurgically from the point of view of armor plate; however, while the latter requires an increase of about 15% in thickness to achieve the same level of protection, it is faster and cheaper to manufacture.
 
 General Steel Castings was a major US supplier of such items and owned among other things two major plants which could serve to provide such items to the tank production program: one in Eddystone, Pennsylvania, and the Commonwealth Steel Foundry in Granite City, Illinois. There was also another steel foundry in Granite City, the American Steel Foundry. Commonwealth Steel had been incorporated there in 1901 but came under the aegis of General Steel in 1929.

With the spoolup to the war, both foundries in Granite City had been producing castings for turret used in the early war tanks for both the American Army and for provision to the British Army. These were essentially the M3 Medium Tank and the M3 Grant Cruiser Tank. General Steel also provided a great deal of material to the Canadian war effort, such as much of the cast material used in the M4A1 “Grizzly” variant as well as the Canadian designed Ram Cruiser Tanks produced by Montreal Locomotive Works (a subsidiary of the American Locomotive Company – ALCO – showing a leitmotif for production facilities.)

During the course of the war General Steel provided both 75mm and 76mm turrets for the M4 series tanks, turrets and components for the T26E3/M26 Pershing, and M4A1 series cast hulls to a number of different assembly plants.

Casting armor parts is not as easy as one would think, as it is not quite as simple as a modeler casting parts in resin which are nearly ready to go out of the mold. Molding steel – especially when it has to provide armor protection of a determined level – requires a great deal of work and specifics. Being easier and faster to produce a cast hull over a rolled homogenous steel welded one does not mean it is a simple task. This book, among other really useful bits on the tanks, explains how it was done as well as shows what the raw castings for US tanks actually looked like.

One fascinating photo shows a Sherman hull and turret immediately after coming out of the mold – imagine a giant practicing voodoo and sticking a tank model full of golf tees and you have a rough idea of the results! (Each of these was a pour gate to ensure a constant thickness product would result.)

Another shows a 4-head 48" Cincinnati Hypro-New Style Electronic Planer type Milling Machine. I was personally surprised, as I recently saw the exact same machine in another photo – but this one was being used in the Ural Tank Factory No. 183 in late 1942 to build T-34 tanks! (One thing not generally well known is how many tool stands and heavy machinery items we provided to the Soviets under Lead Lease!)

Thanks to shared research by Joe “Mr. Sherman” Demarco there are also some fascinating photos. One on page 67 apparently shows a prototype for the M3A1 cast hull which does not match any of the production variants

The book also shows life at the Commonwealth Steel works and what a rough life it could be. The most likely injures appear to be from flying chunks of steel during the milling and cleanup process which required the wear of heavy goggles. Some workers are shown with shattered (but intact) lenses and a safety poster is included as well. Another facet was that for morale purposes the Army would bring in finished tanks to show off to the workers as to where their products were going, as well as captured German equipment to show what they had achieved.

Greg has catered to both historians and modelers with this excellent little book and points out that General Steel used the shield with a G inside as their logo; the G inside an octagon was from American Steel Foundries - Granite City. Greg noted that while General Steel had excellent records to research no such luck was achieved with ASF-G.

Overall this is a fascinating book and one many historians and historically inclined modelers will enjoy a great deal. (I think my own home town, Jamestown, New York, produced ball bearings at Marlin-Rockwell and the furniture factories made rifle stocks but have never investigated to see just what they did!)

Thanks to Greg Jones for the review copy. Available from the author directly for US$27.95 plus $3 shipping and handling (Dr. Gregory T. Jones, 3704 Pontoon Road, Granite City, IL 62040)