The heart of a blacksmith shop
Editor's note: The following is Part 1 of a two-part article on the 15 HP Reid Type A that iron sculptor and blacksmith Joel Sanderson uses to run the line shaft in his blacksmith shop. In Part 2, Joel discusses how he tuned his Reid for line shaft duty.
I make my living in my shop. I am a sculptor and a blacksmith. For years my blacksmith shop has been powered by a 6 HP Fairbanks-Morse Z. Due to a recent addition to the shop, this engine no longer has the power to run multiple machines or the largest machine in the shop: a mechanical power hammer. This led to a search for more horsepower.
I figured that twice the power plus a little bit would cover most anything I would want to do in the future, and allow the engine to drive my current operations without laboring heavily (which I tend to do to the Z).
In a larger engine I needed pretty much the same qualities I had in my smaller engine: common enough not to be too valuable, and to have parts available and easy starting. Initially, I intended to buy a 15 HP Z but soon learned they are not nearly as common as their smaller sisters. In Gas Engine Magazine and elsewhere I began to notice that the two most common engines of the 15 HP size were Reids and Bessemers. It also appealed to me to have an engine that would run on household fuel and not on gasoline.
Through many phone calls I found a consensus that Bessemers may be somewhat more cantankerous to start than Reids. Also, they require considerably more floor space due to their configuration. I would have chosen a 4-cycle engine were it not for their scarcity and cost. Besides, an oil well engine is built for and intended to run long periods without constant attendance: mind free, hands free horsepower - just what I was looking for.
Although the Reid manual does mention the use of their engine in "carbon black factories" no one I spoke with had ever heard of a Reid Type A powering a line shaft. The common reasons given were unsteady running and gas leaks. By studying the Reid manual I saw no reason to be afraid of either issue. This would give me a common engine with a reasonably small footprint and one with a reputation for easy starting. Through what I am about to describe, I now have a non-leaking Reid Type A with a speed variation of 5 RPM while driving my shop, and it starts on the first pull.
Making the Reid work
The engine I acquired is a 15 HP Reid Type A, serial no. 578. It is a right-hand engine with a long crank and has hot tube ignition. I do not have it set up for any kind of mechanical start because it takes off so easily just by pulling the flywheels.
The first issue I had to resolve for this engine's indoor use was to contain any gas leaks. Reids have a reputation for being rather leaky, but I think this is largely due to their application and not to any real flaws in engine design. There are three areas on a Reid that are most prone to leaking gas: the bushings around the mixer's stem, the lower gasket on the main valve and around the main valve stem. The intake also tends to belch gas, but with a long pipe to the outside of the building (as described in the manual) and a functioning intake valve spring, this is not a problem. The relief valve must also be plumbed outside.
To allow a tighter gas fit on the mixer bushings, it seemed to me the mixer stems should slide in and out without any lateral deflection causing binding. I accomplished this by adding a simple little crosshead on each stem before joining them to the governor arm. This not only permitted a tighter fit, but also gives the governor freer movement resulting in smoother running.
On a Reid, the gas and air mixture is forced into the main cylinder under pressure by the charging cylinder, rather than being drawn in under vacuum, as on most 4-cycle engines. This means that the pressure necessary to open the main valve could leak by the valve stem and exit the engine. To prevent this problem, the Reid Mfg. Co. provided their engines with a valve cap, which seals the valve from the room. For additional security I fitted a rubber gasket beneath this cap. New caps are available from John Burns of Oilfield Engine Supplies.
The same pressure needed to open the valve is exerted to the gaskets around the main valve body. Typically these are made of 1/8-inch square copper, top and bottom. These two seals are expected to be crushed simultaneously for a gas-tight fit when the valve body is drawn home. The top copper gasket seals the hot cylinder from the charging cylinder and must withstand the considerable compression and heat of combustion. The bottom gasket seals the cold compression from the charging cylinder, preventing it from exiting the engine. The common test to see if the top gasket is sealing is to make compression with the main cylinder and see if the charging piston is forced out of its cylinder (with its rod disconnected). Unfortunately, there is no such test for the lower seal. If it's really bad, the charging cylinder will not make compression enough to open the main valve into the main cylinder, but a smaller leak could remain undetected.
Since the bottom gasket has to withstand only cold compression from the charging cylinder, I could see no reason to use copper on the lower seat; in fact, I believe it would be a danger to do so. With imperfect machining, wear, pitting, etc., it cannot be assured that the seats would contact simultaneously. To resolve this I continued with the upper gasket in copper but used an O-ring at the bottom seal 0.01-inch thicker than the upper copper ring. This ensures that if the upper gasket is sealing (by way of the piston test) the bottom one must be crushed as well. Soapy water in a squirt bottle is the final test.
Viton O-rings rated to 400 degrees Fahrenheit (Dash no. 249 for the 15 HP Reid) are available from McMaster-Carr, and 1/8-square copper gasket material is available from John Burns of Oilfield Engine Supplies.
This engine cannot be allowed to make a great deal of noise. Although the nearest neighbor is a quarter mile away, I still need the engine to be as quiet as possible. I like to be able to hear my shop's machinery in operation.
For my exhaust system I ran the Reid's 3-inch line down under the floor into an 8-inch pipe. This leads to a buried 900-gallon tank out of which I continued underground for another 24 feet. From here I came out of the ground with a 3-inch pipe standing about 7 feet tall. The effect is amazing: the engine can hardly be heard. In fact, the mechanical clanking from the engine room 40 feet away is louder than the exhaust when standing next to the outlet. The velocity of the gas is slowed so much by the system (mostly the tank) that the fumes just drift away with very little pulse. Inside the shop, (which is a separate building from the engine house) the engine is barely heard.
Another quality I have to have from this engine is constant speed. I think it is very important that this engine powering this facility operate with a governor. (Many Reids run without one.) The 90 feet of line shaft in my shop probably draws 3 HP just to spin. When I use my power hammer, I am immediately pulling another 8 HP. Any other machine running at the time might draw an additional three or four more.
For my RPM not to drop below the rated speeds of the various machines, nearly constant speed from the engine is necessary. This engine loses only 5 RPM from shop at idle to the hammer in full operation. This is approximately a 3 percent drop. While operating my 19-inch lathe, milling machine or 62-inch metal planer, the speed variation is negligible, and the Reid drives the shop without perceptible fluctuation. This is with the Reid running at an idle speed of 165 RPM.
Because my shop does not have natural gas, I am using propane. The pressure I am running to achieve these results is 7-1/3 inches of water (which is about .264 psi). This pressure allows the governor to operate without flooding the engine. I am metering the gas with a standard gas (ball) cock to which I have affixed a threaded and calibrated stop. This assures that when I turn the gas on it always opens to the same setting, and I can dial it precisely with the threads on the stop.
My hot tube burner is running on 2 psi. I have a ball shut-off valve to turn the gas on and off, and I have a needle valve to precisely regulate the flow. This allows me to turn the burner on and off without changing the setting of the flame.
Inserted into the last section of pipe before the chimney I have a restriction acting as a flame check. This restriction causes the gas to begin burning at the base of the chimney and not in the pipe, creating a much softer, gentler flame than is possible with an open pipe. This flame begins at the openings in the bottom of the chimney and extends above the top of the chimney. This heats the hot tube and the chimney very evenly, extending life to both and producing more even impulses.
I have a counter on my line shaft that tells me exactly the number of revolutions it turns. This lets me figure the hours I have run in order to be sure to service the shop at appropriate intervals. It also lets me figure with some degree of accuracy the amount of fuel I am burning to power the shop. Each day when I start, I write down the counter's number and the percent in the propane tank. This way I know my daily readings at the tank are consistent with its average decrease in volume. Because of the necessary time to heat the hot tube, there is about a 10-minute period of burning fuel with no work being done. Once the engine is started it takes another 25 minutes for the engine to come up to temperature and run efficiently. Short, half-hour runs are not terribly efficient, but if the start up time is averaged over a few hours run, the results are more reasonable.
My first check was a 2.64-hour run during which I burned 1 percent of my 500-gallon tank, or 5 gallons of propane. This is 1.895 gallons per hour or $2.84 an hour at the $1.50 a gallon price I am paying for fuel. The second check was a 3.90-hour run during which time I burned about 7-1/2 gallons of fuel, or 1.93 gallons an hour. This comes to $2.90 an hour. These two days averaged $2.87 per hour. Later checks have confirmed these figures. This test was done with light work (lathe and mill), which has ordinarily been done with the Z. When the Reid is made to labor, its water temperature jumps 5 degrees and its appetite goes up to 5 gallons an hour.
My 6 HP Z consumes about 1-1/4 gallons of gasoline an hour to drive my shop. At the recent $2.30 a gallon, this cost me $3.63 an hour to run. Unless the price of gasoline is below $2.30 a gallon, it is cheaper to drive with the 15 HP Reid than with the 6 HP Z.
Reid producing 15 HP: $.50 per horsepower hour of $7.50 an hour at $1.50 per gallon.
Reid producing 6 HP: $.48 per horsepower or $2.87 an hour at $1.50 a gallon.
6 HP Z: $.61 per horsepower hour or $3.63 an hour at $2.90 per gallon.
Of course, to be very accurate with these figures it would be necessary to work each engine on a dynamometer in order to know more precisely the horsepower being generated.
My thanks to all the people who have helped in this undertaking: Special thanks to John Burns for his time on the phone and in person advising me in this.
Contact engine enthusiast Joel Sanderson at: 425 Maple Road, Quincy, MI 49082; (517) 639-4614 or visit his website.