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Whipper shipped/ Lawn Trimmer No one person or corporation is attributed with creating the lawn trimmer however the original lawn trimmers where developed from 1968 to 1970. Prior to 1970, there were no line trimmers, as we know them today. Can you imagine edging sidewalks, driveways, parking lots and shrub beds with hand-held trimmers? Can you imagine how sore your back, arms and legs would be after a long day of pushing a manual edger along seemingly endless sidewalks and driveways? Can you imagine trimming any turf at all without a powered trimmer? Many of us take the advantages the line trimmer gives us for granted.
Line trimmers are one of the most important pieces of equipment in the wide array of landscaping tools. They put an edge on sidewalks, shrub and flowerbeds and parking lots. The time we save by using these tools is something people may take for granted these days. Since the early 1970 s (when the first powered line trimmers appeared), the machines have improved with stronger line, more attachments and better engines. This is all in the aid of giving more time and quicker action in the increasingly hectic lifestyles of today.
The basic trimmer works by the engine driving a multi-bearing supported hardened steel shaft housed in an aluminium tube through a centrifugal clutch this shaft is connected to a head that holds a nylon line that spun at high revolutions per minute (RPM). This nylon line then cuts the grass by hitting the blades of grass at high speed, this cause the grass to be severed at the point of impact. Thus trimming the grass. The first models were petrol powered, as electrical lawn mowing devices had gone out of fashion due to the danger of electrocution after accidentally cutting the power cord.
The original petrol powered trimmers where two stroke engines around 28 to 32 cubic centimetres in capacity powered by a mixture of super petrol and oil, today they are much the same with the exception of being powered by unleaded petrol and oil, but becoming more popular is the electric trimmer. A leader in engine technology Honda has taken the latest accomplishment, with Mini 4 -Stroke engines. Powered by the only 360 ' inclinable (can be turned on any angle and still run properly) 4 -stroke engine available today, the new Honda trimmers deliver smooth, dependable power and unsurpassed fuel efficiency. They require no special gas / oil mixtures so there's no chance for improperly mixed fuels.
And they " re remarkably quiet, virtually smokeless and environmentally friendly. The New 4 -Stroke Honda engine The two-stroke engine cycle produces lager amounts of smoke and noise than four stroke cycles, this is due the fact that there is less time for the fuel / oil mixture to combust completely and the fact that two strokes run at higher engine RPM (revolutions per minute) about 7000 RPM compared with around 4000 RPM of four strokes. This increased Rpm causes greater vibration of the engines cooling fins and in turn more noise. The increased RPM means that more air and fuel is going into the inlet port via the carburettor of the engine which means more induction noise, silencers are used but noise is still high, with all his extra air and fuel going in to the engine extra exhaust gases must come out meaning greater exhaust noise, mufflers do help but a high decibel reading still is present. A typical 2 -stroke trimmer
Airflow carries the atomized gasoline to the engines cylinder, where the aerosol is ignited. Those trimmers powered by Super petrol and oil mixtures have a quantity of lead in the petrol, once combusted this lead is expelled by the exhaust unit of the engine and falls to the ground in around 12 feet. This lead (allegedly) causes harm to humans and the environment however no evidence of lead poisoning due to engines has been produced. Many people campaigned to have this lead removed from the fuel, they succeeded and unleaded petrol was soon produced. However unleaded petrol has no lead, which acts as a lubricant so more oil would have to be used, this means more smoke will be produced as the oil burns less efficiently. Also unleaded petrol contains high quantities of Benzene, Xylene, heptane (add more) these are known carcinogens and as carcinogens cause cancer.
It has been medically proven that these chemicals are carcinogenic and there is growing support to the theory that the increased amount of cancer sufferers is closely related to the increase in use of unleaded petrol. Heads and line feeds in order of invention Four types of spin-trimmer heads are available and they are classified based on how they dispense line: Fixed-line heads do not hold additional line. You must use pre-cut lengths of line for replacements. This is how the original trimmer head worked. Manual heads require you to stop the machine (turn it completely off) and manually pull or unwind the line that is wound inside the head.
Was soon developed to save some time so that the work could be done more quickly. Semi-automatic heads require you to tap the spindle head on the ground (preferably not on concrete) during operation when the throttle is engaged. The tapping and open throttle causes the line to advance and feed out the guide holes in the spindle head. This is due to the creation of more sophisticated components that can withstand the high rotational forces. Automatic heads feed the line automatically during operation when the throttle reaches a certain speed.
The most recent advancement but is yet to become wide spread. Statistically speaking, tap-and-go (Semi Automatic) heads are the most popular variety. Most users view them as more convenient because you can control line length without stopping the machine. However, manual heads remain popular as well. String types String diameter varies greatly and comes in round-cut and edged varieties. Much debate occurs over which type and diameter trims grass the best.
Unfortunately, there is no definitive answer to this debate. Diameter plays an important role in how long most string tends to last. Typically, the thicker the diameter, the longer the string will last. Diameters range from 0. 066 mm to 2. 60 mm. You must refer to the owner's manual to know what size of string will fit inside the trimmer's head. Manufacturers market many different types of string.
Some say that their string material is more durable, due to stronger and higher quality nylon others propose the shape (smooth or edged) enables the string to trim turf more efficiently. It should be recognised that some edged strings do not feed well in automatic-feed heads. Other types of string may "float" erratically while spinning, resulting in an uneven cut. Some string may cut extremely well, but also wear more quickly. High-quality string-specifically an anti-weld or anti-fuse line. Because the string pulls when it hits vegetation, heat builds up inside the head and less-expensive string may fuse together and clog the unit.
If you must use a softer string, spray it with a silicone spray after you " ve re-loaded the spool. This, although not a complete solution to the fusing problem, helps reduce string fusion. Popular nylon line lawn trimmers are now the fifth leading cause of penetrating eye injuries. Operating at speeds up to 7000 revolutions per minute, the trimmers may spin off tiny fragments of the nylon line, which can enter the eye along with dirt and grass debris, causing corneal lacerations and fungal infect...
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