Last fall I had the pleasure of attending the Bonneville Mill Fall Festival in Bristol, Indiana whereas there were quite a few old tractors, antiques, old time farming demonstrations and the like. One of the first things that I came upon while walking down to view the old tractors was a sawmill demonstration. I had been to this festival several times in past years and this sawmill demonstration was always powered by old steam engines.
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When the unit is hooked up to the pulleys on the sawmill, it all looks like that in this photo here on the left.... the truck serving power to the mill (this photo not really a good one....sorry about the quality)
From talking to Todd, I was able to obtain a little more history on the truck. Here is some of what I was given........
It seems that in the old days of threshing, steam engine power was the only power strong enough to run the separators (threshing machines) but they were huge pieces of equipment that had to move from one farm to another. When farm tractors were eventually developed they took they place of the steam engines as a power source. In both cases however, moving from one farm to another was a long process at 2 - 3 miles per hour. Getting the proper amount of power to machines in a much quicker time frame was the primary reasoning for this truck's existance!
The right hand engine has a Pierce governor belted to the crankshaft, which controls the speed on both of the engines. The gear train on this unit is two ring and pinion units for power input and a belt pulley on one of the wheels. Each engine has its own starter, clutch and cooling system (although only one generator is actively working at a time). The belt pulley was made from a Ford truck wheel and blocks of hardwood which eventually drives the belt.
After lining up the belt with the saw equipment, the right engine, which has the governor attached, is started up first. Once it is running, then the other engine is started. With both transmissions in high gear, the clutches are engaged (both clutches are engaged at the same time via a single clutch lever). The throttle operates this way as well.....that being a single control which was made from an emergency brake lever. A 55 gallon oil drum is used to hold the fuel needed.
There is a lot more history and detail about this old truck in an article written by Pat Ertel that appeared in "This Old Truck Magazine" (which is now called "Vintage Truck Magazine") back in November, 2001. You might try to find that article on their website for those of you who might be interested.
It sure was a pleasure to meet Todd, a grandson to Lamoin (who passed away in 1976) and to watch this old truck in action. This family exhibits the truck at many shows around the Midwest and if you ever get to see it operating, it will most likely amaze you..... as it did me.
Enjoy!