Prony Brake Measuring Steam Engine Horsepower - Mt Hope Show

Uncut video of a historic Prony Brake measuring the horsepower of 2 different sizes of Baker Uniflow steam traction engines.
This Prony Brake was built by A. D. Baker Company for use in testing engines prior to shipment. It is built around a standard Baker flywheel, a platform scale, and various pieces of iron and wood. It was donated to National Threshers Association of Wauseon, Ohio by A. D. Baker himself, who was one of the founders of N. T. A.
The lever arm and platform scale give a precise measurement of torque in foot-pounds, and the tachometer provides RPM, to allow computing true horsepower. The balance scale is inherently accurate, and extensive work has been done to calibrate the tach. The brake is lubricated with animal fat, and water cooled.
It is typical for engines like these to significantly exceed their rated horsepower, that is the honest way things used to be. The 21-75 was recently completely rebuilt, and the piston rings are probably not fully seated yet. The owner has observed that each time the engine is operated, power increases, and it runs smoother.
The 43.7 HP on the board was posted by the 1 year old "nominal" 6 HP Advance.
The 23-90 finished at 110.7, but had more to give.
Mount Hope Steam Show
Mount Hope, Ohio
August 1, 2015
#506
150801d Prony Mt Hope

[@MeadowFarmer]

Beautiful equipment. It's wonderful that so many people put time, money, and effort into preserving living history. Thanks!

[@oldbear52]

Thank you for sharing this interesting and educational video!!!

[@raymiller5294]

great video of a two bakers on the belt.

[@nightlightabcd]

Nice engine and a very well done video.

[@paddymickiemickie8221]

Brilliant

[@11jimcleveland]

Great stuff!!!!

[@mattseymour8637]

Good video. What do these numbers mean and what was the hp of the engine?

[@SteamCrane]

The first number is the tractive horsepower, the second is the belt (ie PTO) horsepower. These are guaranteed minimum actual horsepowers, as opposed to modern "peak" horsepower. In practice, these engines exceed the rated power by a substantial amount. Thus the 23-90 produced more than 110 horsepower here.

[@mattseymour8637]

@@SteamCrane That makes sense and also you have to remember that Traction Engines and steam engines produce alot more torque than internal combustion engines and produce a power stroke every stroke unlike a combustion engine.
So although the hp might seem low for a traction engine because they produce alot of torque they are very powerful!

[@UnitCrane514]

That's back when Horse Power truly meant HORSE POWER! You can't tell me that the little 5hp on my snowblower equals 5 plow horses! Who do they think they are foolin?

[@OnlyTheEd]

110.7 snap. :-(

[@SteamCrane]

Spoiler alert!