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Discussion Starter · #1 ·


The Rivarossi Big Boy has arrived.

This is what Ontracks have to say about it:-

QUOTE During the late 1930s, the Union Pacific often used helpers to move trains from Ogden to Wasatch. The UP wanted to simplify this move so they asked their "Department of Research and Mechanical Standards" to design a locomotive that could pull a 3600 ton train unassisted over the 1.14% grade of the Wasatch.

The designers determined that to pull a 3600 ton train, a tractive effort of 135,000 lbs would be needed. Assuming a factor of adhesion of 4.0, the weight on drivers would have to be 4.0 * 135,000 = 540,000 lbs. Given an axle loading of 67,500 lbs each, this would require 8 drivers or an x-8-8-x wheel arrangement. The designers agreed upon the 4-8-8-4 design. Next, the horsepower and cylinder sizes were computed based on 300 psi boiler pressure. Although they weren't planning to pull these freight trains at 80 MPH, the DoRMS designed them for 80 MPH in order to have a sufficient factor of safety built into the design. What resulted is considered by many to be the most successful articulated steam locomotive ever built. 4000 was delivered to Omaha at 6PM, September 5, 1941 and the class quickly acquired the nickname "Big Boys"!

This fully re-tooled model features double cardean transmission with flywheels, metal chassis, front headlights and comes DCC-ready with NEM652 interface, length: 475mm

Not too sure how many UK stockists will have this as its a Hornby International product although Guagemaster, Ontracks and a few others are heavily into European HO modelling.

Happy modelling
Gary
 

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Discussion Starter · #6 ·
QUOTE Makes you wonder why so many manufacturers produce a model of a loco that only had 20 in it's class

Because every American HO modeller wants one?


I would guess that the Big Boy is the HO equivalent of the "Flying Scotsman" and is there to showcase the rest of the range of a manufacturer.

That Trix model does sound pretty good also. It seems that HO modellers are spoilt for choice. I would guess that DCC operators would go for Trix and DC operators would go for Rivarossi.

Happy modelling
Gary
 

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A Garret is a tricky one as should it be produced in OO or HO scale?

Or both? HO would probably be a better scale to choose commercially. There would be massive international interest and it would be a flagship model for any company with the ***** to have a go!

Absolutely agree that it would make a great model to run on any layout and with twin motors it should be able to pull 30 coaches!


Isn't there an Australian manufacturer already offering a ready to run example at a price?

Happy modelling
Gary
 

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Discussion Starter · #20 ·
Walthers are taking a very keen interest in the Hornby International distribution deal.

The retooling may refer to the chassis although there is a possibility that the body has been retooled as the old Rivarossi tools may not have been compatible with the manufacturing equipment in China.

Happy modelling
Gary
 

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Didn't Lima purchase Rivarossi in the 1980's?

Not sure on this however I do recall seeing the Rivarossi Big Boy on sale in the late 1970's. Has it been retooled since it was first produced?

Hornby claim to have done a lot of work on the Lima tools to tighten tolerances, reduce mould lines, and generally sharpen things up. I suppose its a reworking or an upgrade of existing tools and as a result the latest release should look better than previous examples.

Happy modelling
Gary
 
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