BOAZ: A Mini Wheat Harvesting Machine
Growing Wheat Small Scale Means Acquiring the Right Small Scale Equipment
By Benjamin Hoffman
Choosing the right mini wheat harvesting machine for our small-scale operation took research. We settled on the BOAZ mini-combine.
Bob Mowdy and I have independently fooled around with small grains for about 10 years. Last year we began working together and sharing the frustrations. We both want to grow grains for learning how to make whole wheat bread, and for cereal and livestock, on a small scale, but unless you go back to scythes or sickles for harvesting and winds and buckets for winnowing, you are stuck. Gravely walk-behinds cut too low and gather too many weeds, and sickle bars on tractors push too many stems over. There are plans on the internet for modifying chipper-shredders for threshing and several designs for winnowing, but harvesting, other than scything (difficult for lefties), is a problem. We needed a mini wheat harvesting machine.
Bob researched a list of farm tools and equipment and ran across some Chinese mini-combines on the internet, and we investigated importing one. Currency exchange, customs, EPA regulations, dealing with people you don’t know and unknowns finally steered us to Eddie Qui, of EQ Machinery, in Medford, Massachusetts. Eddie imported a slightly larger machine that we wanted, but we bought BOAZ from him. BOAZ is a three-wheeled machine, 11-feet long, with a 13 HP gasoline engine, and weighs in at 948 pounds. We preferred diesel, but the close proximity of exhaust gases to the operator makes gasoline exhaust “safer.” Cutting width is 2.62 feet (one meter) and productivity is about 1/4 acre per hour (when everything runs properly). The machine was designed for rice and wheat, and therein lies the problem with tall grains like rye and triticale.
When cutting grain, you need to cut higher than the weeds in order to reduce the load of greenery and weed seeds going into the threshing chamber. BOAZ has two cutter-bars, both adjustable in height. The upper bar cuts the grain heads and can raise as high as 42 inches while the lower one cuts the stubble four-to-six inches above ground level. Having had problems with machine harvesting in tall weeds, we were especially pleased with the cutting aspects of BOAZ.
We had seen videos of BOAZ in wheat, barley, and rice, and it worked well. But we tried it in five- to six-foot rye. The rye had been broadcast, the stand was not dense, the weeds were well developed and rain had loaded the grain heads with water and caused the spindly stems to droop in all directions. Even when raised to the maximum elevation, the intake reel pushed many of the stems away and the cutter bar attacked stems at an angle and pushed many of them to the ground rather than cutting them. Add to that a poorly adjusted butterfly valve controlling airflow to the bag, and we ended up with 1/3 of a bag of grain and 2/3 of chaff until we got smart and adjusted the airflow.
Our rye patch was a demo for several knowledgeable observers who were machine-savvy. Though disappointed with cutting rye, we solved several problems in learning to operate the machine as well as some problems inherent in the machine’s design. Subsequently, we have harvested oats and two different varieties of wheat. The butterfly valve that separates grains from chaff needs to be fine-tuned to the size/weight of grain kernels and the chaff. If the grain is too green, the chaff may hang onto the kernel and it will be passed out with chaff.
The basic mini wheat harvesting machine design is simple and straightforward and the quality of components seems good. There is a hand clutch to engage the threshing mechanism and a hand clutch for driving the machine. When threshing, although the manufacturer recommends full throttle, we have found that 1/4 throttle works well with the larger engine. First, you engage the thresher, then the main drive, and once everything is turning, the engine speed can be lowered. Hand clutches to control each front wheel are conveniently mounted on the handlebars. Elevation of the grain head uses a hand-pumped hydraulic cylinder next to the operator’s seat and elevation of the stubble cutting bar is done with a hand control that cannot be confused with any other controls. The seat (and angle of attack) is raised and lowered with a small crank in front of the driver’s seat.
As a model train fan, I have been impressed with the quality of tiny drive trains and electric motors made in China, but less impressed with the alloys and welding in some garden tools. And BOAZ has sacrificed some niceties in order to keep the price down. Operating conditions are not attractive to a typical American worker, and low cost means minimal operator comforts. No air conditioning and stereo. Getting into the seat is a bit more difficult than getting into the saddle on a horse with his tail in the air and the three-wheel design leads to some problems in control when backing. To steer, the operator uses his feet to direct the single rear wheel and independent hand clutches (no brakes) for each front wheel. Initially, unless you have strong legs, and are prepared, if you hit a small obstacle while backing, the wheel can turn 90 degrees before you can control it.
We identified several potential problems and safety hazards with BOAZ. First, there are three speeds forward and one reverse. Use third gear only on a paved road, after you are experienced with second, and wear a safety helmet. To control the throttle, the operator must bend down and reach the side of the engine for the fuel control lever, an awkward, potentially unsafe situation. This can be easily remedied. When speed must be cut in an emergency, the operator must shut off the ignition or throw in the hand clutch—neither is good for the engine. Another minor problem is the close proximity of the exhaust to the operator’s left knee, partially solved by a seven-inch exhaust extension.
Normally, I buy farm machinery in the crate and assemble it myself or with Bob’s help. Eddie Qui insisted that his personnel were the only ones qualified to do so, and lacking a good English operator’s manual, this was somewhat true. However, after about four hours of use, we removed all of the guards and covers from the machine, cleaned it thoroughly and lubricated it. Many of the zerk (grease) fittings were loose, some were missing and two that should have been 90 degrees were straight and could not be serviced. Several bolts were loose, one was missing, and one had no nut. While it would be nice to have zerk fittings (eight) for the pickup reel, oiling every four hours with summer-weight bar and chain oil (which has a “sticker”) should suffice.
If you buy a BOAZ mini wheat harvesting machine, there are three absolute musts before you operate it. First, do not accept delivery without an operator’s manual written in understandable English. Second, read the owner’s manual and become thoroughly familiar with the machine. Third, remove all guards and covers, check every zerk fitting, look for missing zerks/bolts/nuts, grease all zerks, and oil all friction points that do not have zerks; also do this after every four hours of use. Keep a supply of straight, angled and 90-degree, 6 mm zerks on hand. Some models were shipped with an idler pulley drilled for a zerk fitting but with insufficient clearance for it. Though there are grease gun fittings that can service this pulley, have a local machine shop make a three-inch pulley to replace the two-inch pulley on the machine.
In addition to operating as a self-propelled combine, BOAZ can do stationary threshing of small grains, dry beans, and corn. For safety in stationary threshing, the intake reel and both cutter bars should be disconnected, a fairly simple task.
We did a cost estimate on BOAZ based on several assumptions:
• The machine will last 20 years, averaging eight hours/day for six days on winter grains, six days on spring grains and four days as a stationary thresher (dry beans and corn), a total of 16 days or 2,560 hours over 20 years. At its rated productivity of 1/4 acre/hour, or about 10 bushels/hour, it should produce 25,600 bushels. At a purchase price of $5,000 (ignoring interest and insurance), depreciation ($1.95) and taxes ($0.41) over 2,560 hours are $2.36 per hour.
• Operating costs—fuel ($3.50/gallon), lube (30% of fuel) and maintenance (60% of depreciation) would average about $4.39 per hour.
• Total costs are $6.76 per hour.
• At its production rate of 1/4 acre/hour, cost per acre is $27. Divide that by the yield (bushels) per acre to get cost per bushel.
• Note: these costs ignore labor and movement from field to field.
So why did Bob and I stick our necks out on BOAZ?
• We both want to raise grain and have played around with a variety of tools for 10 years, without success.
• We have several small fields, ranging in size from 0.25 to four acres, some so small you can’t turn a regular combine (if you could attract one).
• We don’t like GMO grains and those grown with chemicals.
• We hope to meet our own needs for baking, cereals and feeding backyard chickens and other livestock.
• The economic condition of this nation is such that a useful machine is worth more than money in the bank.
Though our initial use of BOAZ has not been totally satisfying, we are optimistic. We need good stands of grain about 36-48 inches high, low weeds, patience, and experience. But harvesting grain is just the tip of the iceberg. Because of the high rainfall and humidity in our area at harvest time, we must harvest grain early, with a high moisture content, but have built two simple dryers. Now we need to build a grain winnowing/cleaning device.
What mini wheat harvesting machines have you tried for small scale grain production?
To see BOAZ in action, check out www.eqmachinery.com for videos of the machine. BOAZ—A Chinese Mini-Combine.
Originally published in the November/December 2014 issue of Countryside & Small Stock Journal.