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Assembled Cylinders

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sbwhart:

--- Quote from: Yorkshireman on July 31, 2009, 03:51:51 AM ---Stew

You mean cylinder castings from the 'established suppliers', do you?


Yorkie

--- End quote ---

Hi Yorkie

Yes its established suppliers I'm on about  in my case Reeves I've built/building two models using casting from them and have had to return castings to them three times at my expense and I've replaced a US casting with a fabricated part rather than returning it. I also visited Reeves with my wheel castings as the driving and driven wheels didn't quite match, by the look of them they'd come from two different suppliers, the attitude although they were very nice about it was thats what we've got take it or leave it.

One thing that suprises me is that suppliers don't seem to have taken advantage of CNC machine tools in the supply of part, if you look at some of the castings it would be a easy job for them to be roughed out from a chunk of continuous  cast material by CNC to a stage where the customer/modeler could finish them off, perhaps there is something in the economics I don't understand in this.

Cheers

Stew

Yorkshireman:
Stew

The CNC approach would imply that 'the suppliers' would be run by engineers, and that is not the case. It is also an enormous initial investment. Throwing a pattern together and having it cast again and again is easy and should indeed drive the costs DOWN when producing larger batches. With CNC each and every piece does require the same amount of costly machine time. The quality is orders of magnitude better, though. It depends how modelers would value their own time.

At Berliner-Eisenbahn they introduced spark eroded loco wheels, beautiful and correct in every aspect: oval and tapered spokes even with little webs at the ends, made from tough steel. One could even have the year of manufacture carved into the back. Such a wheel is quite expansive, but if one would just take the minimum wage for producing a wheel like this from a casting (assuming it was possible), then it becomes resonable again. Last year I showed a driver wheel for a 7.25" loco like this on my club's stand in Harrogate. Most people wondered why the wheel was tied to the table, only some guys realized what it was, and only then the wheel caused some commotion.

I agree that producing parts from continuous cast material should be feasible. But how many modellers would rather just a 'cheap' casting?

Yorkie

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