The top-handled chain saw is one of the greatest developments in arboriculture. This article is to offer some history of the chain saw and focus primarily on the reason behind the modern arborist chain saw, also known as the top-handle chain saw.

The modern chain saw has been in mainstream use since the 1970s. The first saws were developed as far back as the 1940s, however the earlier designs were heavy, the cutter chain was fashioned after a crosscut saw and the kerf filled routinely as it was plugged with chips. This combined with a float carburetor meant the engine could not be turned on its side to make an angled cut like we do today. These chain saw designs, while intriguing, presented little practical value.

During the 1950s and into the 1960s the modern chain saw chain, driver and cutter design were developed. During this time, work was also underway in developing the non-float carburetor. These two innovations when applied to the chain saw made the use of the chain saw easy and efficient, encouraging an increase in usage and sales. From the 1970s until today, modern chain saw use has become extensive and with this increase quickly came new and innovative designs such as the top-handled chain saw.

The reason the throttle handle was moved from the rear of the saw to the top of the saw was for manoeuvrability in tight spaces. When working aloft, arborists often find themselves in confined spaces such as suspended from a rope, work positioned on spurs and lanyard or standing in an aerial lift bucket. Moving the handle from the traditional rear position to the top of the saw allows the operator to work ergonomically and make efficient and precise cuts as required during pruning or removal.

Often a design meant for one purpose is adapted and used in ways in which they were not intended. For example, many assume that the top-handle saw was meant to be operated one-handed, when in fact this was not the reason for the innovation. This is like thinking a dime was made to be a temporary screwdriver. Many arborists have learned bad habits of using the top-handle chain saw one handed. This is a dangerous way to work and many have learned the hard way to stop doing this dangerous practice only after being severely cut on the hand, forearm or wrist.

Top-handled saws are engineered to help arborists work in tight spaces and operated as all chain saws should be, with two hands on the saw when in use. The left hand holds onto the saw body handle or forward handle and the right hand operates the rear or throttle handle. It is worth mentioning that operating any chain saw “left-handed” puts the operator at risk due to how much closer the bar of the saw is to the cutter when cutting and should be avoided.

The latest innovation is the battery saw. Due to its popularity, a top-handled or arborist chain saw has been on the forefront of the battery saw revolution. The top-handled battery chain saw has become very accepted and popular. The main caution with this new design is the absence of noise, which is also one reason it is liked. However, it is increasingly important to identify the drop zone on work sites when battery saws are employed aloft. Ground workers used to hear the roar of a gas engine and equate this with falling debris. It is very important to maintain regular verbal and visual contact between workers aloft and those on the ground.

The primary and first recommendation for operation is to use two handson the saw, with the correct hands on the correct handles. The exception to this is during start-up.

STIHL top-handled models have safety features to protect the operator. It is virtually impossible to cut your hand arm or wrist if both hands are on the saw. The safety and operational features of all STIHL top-handled models are:
• Inertia chain brake. This can and should be manually applied whenever the saw is not in use. It also acts as an emergency stop in the event of kickback and in this application, works independently of physical contact due to inertia, much like a seatbelt grabs during a collision due to the sudden jolt.
• The chain catcher pin. This is located on the bottom of the saw and in the event the chain derails or comes off the bar, this catcher pin will grab the chain preventing it from flinging around and cutting the operator.
• Throttle interlock. This feature is on the throttle handle and is to ensure that the operator hand is firmly on the handle before running the saw.
• Viewing ‘windows’ or openings. These are engineered into the brake handle to allow the operator to view cuts being made while in a suspended/aerial confined type work location or position.

A final note; due to the specialized nature of the design and unique purpose of the top-handled chain saws for work aloft, the STIHL operator’s manual advises against the use of the top-handled chain saw for cutting on the ground for work such as limbing and bucking.

Dwayne Neustaeter Sr.
President and Founder
Arboriculture Canada
www.arborcanada.com