Tiny Power M twin
Just a page to show some pics and video of an unusual 3 X 3 X 4 simple twin steam engine that Tiny Power
produced around 50 years ago. This engine was bought in 1958 in kit form by Monty M Stout of San Francisco
from Charles "Pop" Arnold, the same year he began work on it. Probably due to lack of available machinery,
the kit was started and some of the pieces were spoiled, blown dims etc. Some of the work was really good
though. He wrapped all the parts in newspaper from 1959 and as far as we know, put it into a storage locker in
that same year. It stayed there until the spring of 2009 when it was discovered and sold. We bought it and
after a few days of trying to figure out with no blueprints where they left off fifty years ago, we restarted the
build. A few parts were missing and as mentioned before, some were damaged and had to be replaced.
Luckily, Tiny Power is still around and a few emails to Ronnie got us all the parts we needed to finish, plus a
few assembly tips. They don't make this exact kit anymore and from what I understand, it was only offered for
one year and discontinued, only the single M continued. Most of the castings are the same with subtle
differences, so the new parts were able to be machined to fit. They do make a Twin M now, but the valve
chests look away from one another. These facing both the same direction have one big advantage, the
engine is a lot shorter, has a much smaller footprint than it's modern day descendant. This engine would fit
where most one-lungers do now. And of course, it's a twin simple with the crank throws set at 90 degrees, so
it will start anywhere in the rotation. A huge plus. They should consider offering this engine again. They would
only need to produce a base. They do offer this basic engine now in a scaled down version to use in R/C
boats.
Some of the oddities/differences of this engine:
The cylinder bore length is 4.75" and with a 4.00" stroke, the .250 piston rings had to be moved a little closer
together. The overall cylinder length is .500" shorter than the new engines.
The Stephenson links are only .375" thick as opposed to the modern engine which are . 500" This means the
ends on the valve rods are a bit smaller.
Every part of this had layout lines and notes, all
performed meticulously. My theory on this was,
he was probably a lathe hand, and was taking
these parts to work and running them on breaks
etc. Common thing for machinists to do.
We outgrew our old building and had to move to a larger facility. This laid on a pallet, all sprawled out and I
ran a detail here and there and then finally broke loose and finished this thing up.
It was quite a build.
The first step was to go through and try to figure out where to start. I ran some of the simpler details like the
eccentrics and straps add odd times. But I had to start thinking about the whole assembly and the best route
to go.