Roger Bailey contributed:-

> Years ago, an acquaintance of mine purchased a set of
>Schmoyer castings but, to my knowledge, he has not completed the project
>(machining or assembly). Would these be useful as patterns to reproduce the
>missing pieces? Let me know if this is worth follow up.
>

Unfortunately aluminium shrinks 3/16" per foot of pattern size when cast 
so castings cannot be used as 'patterns for themselves' although it 
should be possible to use them to design replacement items in steel for 
modern 'shell moulding' techniques.

Pattern makers use special rulers which are 'expanded' by the appropriate 
shrinkage factor for each material (e.g. 5/32" for bronze).  These were 
always carefully controlled because if they found their way into a normal 
workshop could cause as much havoc as a today's computer virus.

If anyone knows of a set of Schmoyer castings for sale I'd love to hear 
about it as I've always admired this wonderful concept and didn't realise 
they might still be available in this form.  It's an ill wind....

Tony Moss.

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