SIM Co. Model No.40 Watt Junior


This rather unusual engine is a SIM Co. Watt Junior. It's in pretty good condition, missing the safety valve and the end
of the piston valve has snapped off. Turned out that the piston valve was siezed in the valve chest. I was able to remove
it but i will have to make a new one.

Thanks to my friend and fellow model steam engine collector Charlie Miller i now know a lot more about these
engines. Although manufactured by the Specialty Instrument & Machine Company ( SIM Co) these model steam
engines were distributed by the Harvey - Miller Corporation. There were five engines in the range three horizontal
and two vertical. The horizontal engines were, The Watt Master, The Watt Senior and the Watt Junior. The vertical
engines were The Watt Special and The Victor.

Thanks to Bill who got in touch with me with a question about this engine i can now date it fairly accurately.
He was given his engine as a Christmas present in 1948, so we can date these from late 1940s to early 1950s.

Video here.

This advert was very kindly supplied to me by Charlie Miller.
















It has a very strange safety valve. Fortunately i have another engine with the same valve. It is a small cube of what appears
to be stone with a brass rod through the middle. This simply sits on the boiler filler hole.







Here is the engine after a good clean and with the new piston valve fitted.













This is the brass version of the safety valve i made for it.




Now with the final missing pipe fitted.






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