A little something about Stuart Models:  Click Here

I have long admired the Stuart rendition of the Beam engine...a design perfected by James Watt in 1794.   The unique feature Watt brought to bear was a mechanical linkage named the "parallel motion" which can be seen as a series of interconnected rods off of the right end of the rocking beam in the photo below and straight on in the end shot that follows.

Watt's double-acting engine design produced power on both the upward and downward strokes necessitating a means to keep the piston and pump rod moving vertically yet perfectly parallel to one another.   So much for the textbook definition...it is simply beautiful to watch in operation, especially at slow speed as can be seen in a video further down this page.

Stuart has developed TWO sizes of the beam engine, this one and a much larger Major Beam version.   This is a pretty sizeable engine in it's own right with the following key specs:
- length 13 inches, height 12 inches and width 6 inches.  It weighs about 12 pounds
- flywheel is 7 inches in diameter, with bore at 1 inch, stroke at 2 inches

I'm working on a paint scheme for a future date, but for now wanted to capture it as cleaned up and operational.  I say cleaned up because although run very little, the residual oil had collected years of dust...it took many hours of cleaning with cotton swabs and paper towels to get down to clean metal...perhaps it was a protective coat after all because the metal once cleaned up was in perfect condition.

I'm finding over time that my collecting whims are shifting towards fewer, better and more machinist oriented pieces vs. just one more of "something".   I recently (late '07/early '08) sold off a number of steam engines and accessories I had lost interest in and decided to dedicate the cash to a few really nice additions. 

This piece is an example of my current pursuit of higher quality, a Stuart S50.  This is an elegant model "Mill Engine" of the type used to power small factories in the north of England during the mid-nineteenth century.



Most of the pieces in my collection have undergone a complete restoration by me to get them to this sort of quality level.  For this piece, the top notch fit and finish was purchased...I did nothing to this one but run it upon receipt, I could not improve on it.



This S50 was built in 2007 by John Coleman, a US machinist who sold quality engines, boilers and fittings on eBay via his eBay "store" called "The Steam Chest".   Sadly, John passed away in July 2011 and his eBay store is no more.  He will be missed by the model steam community... R.I.P. my friend.

John built this engine up from a 1980's Stuart Machined Kit, noting that Stuart pieces from the 1980's showed better workmanship and more extensive use of brass and bronze vs. cast iron today.   A check with the Stuart website confirms the greater use of cast iron in today's S50 vs. what was used in this engine.

The S50 spans 8.5 inches in length with a 5/8 inch bore and 1 1/4 inch stroke.  This particular example has a larger than current flywheel as noted in the list of features that follows.



Extras not found on current Stuart S50's but included on this one:
  -larger 3-3/4" flywheel diameter (vs. current 3 inch offered)
  -all bronze cylinder, steam chest & cover (vs. current iron castings)
  -dummy cast headbolts were machined off & replaced with real bolts
  -working brass governor with adjustable high speed steam cut off
  -live steam displacement lubricator
  -brass & bronze gate valve on inlet side
  -brass drain cock on cylinder end
  -brass oil cups throughout
  -mounted on a vintage piece of American Black Cherry wood & brass feet



I previously owned a Stuart S50, but it seemed a poor doer and I sold it on.  Being a machined piece, the finished product is very dependent on the skill of the machinist and my last example was not near as fluid in turning it over as this one. 

As can be seen in the following video, this S50 lives up to it's name as an elegant workhorse of the Stuart line and I am very pleased with the finished product.

CLICK HERE for an instant video

Such is the case with the 10H, simply sold as a "factory made" engine by a secondary seller.  I assume that meant it was one of the finished engines Stuart sold, but aside from the fine pinstripping on the engine, I have no way to verify it's parentage.

The 10H is the horizontal version of the 10V that follows this section.  The 10H spans 6 inches in length, and has the same 3 inch flywheel and 3/4 inch bore and stroke as the 10V. 

Stuart notes the 10H will run from 200 rpms to 2000 rpms making it well suited for driving other models such as their Dynamo or Oil Field Pump (sure wish I had those!!) 

Suffice it to say this little engine runs beautifully on live steam from a 3" Jensen boiler or compressed air.  I still have not decided how to mount this engine, but most likely will put it on a nice wooden base.

This example and other Stuarts are in a different class than the rest of my collection...not so much from a size standpoint, but a precision machined engine like this really showcases an individual's work and is closer in reality to the real engines these are based on.  Lovely stuff.

Just for kicks I hooked up the Stuart 10H to the exhaust coming out of the Stuart Beam, both ran just beautifully, a bit slower, more scalelike...but nice...see the video below: