Although some might consider the chainsaw not to be a true DIY power tool in the strict sense, it is, however, one of the powered tools that DIYers often have in their ‘toolbox’. Traditionally chainsaws have been petrol engine-powered machines that were expensive, making them an often unjustifiable purchase for most DIYers. However, in today’s world of advancing electrical technology, even the humble chainsaw has gone electric, with reasonably-priced mains electricity-powered and battery-powered machines now readily available to the ordinary consumer. In this review of the modern chainsaw, we first look at what a chainsaw is used for and how it does its job, before examining what characteristics to look out for when purchasing one. Then at the end of the page, we compare the technical characteristics of actual chainsaws sold in the UK with a view to identifying the best chainsaw for DIYers to buy.
The Use and Functioning of a Chainsaw
Chainsaws can be used for quickly slicing through larger wooden structures such as logs and garden branches. Functionally, they are not unlike reciprocating saws, although chainsaws tend to be used for cutting wood of greater girth, and they are not used to cut other types of materials such as metals and plastic as do reciprocating saws. Structurally, the chainsaw consists of a powered motor that drives a cutting chain at speed around a guide bar. The metal chain that travels along the guide bar is bladed and when the chain makes contact with the workpiece material the cutting teeth are dragged through the wood to make the cut.
The Petrol-Powered Chainsaw
Probably the most familiar chainsaw type is the petrol-powered chainsaw which is mostly favoured by tree-felling professionals for its power and speed of cutting, as well as for its ability to cut a large amount of wood on a single tank of gas. It also has the advantage of being untethered unlike mains electricity-powered equivalent machines that need to be plugged in. However, for the DIYer, there are a number of things to take into account, many of which are disadvantages, when considering buying a petrol-powered chainsaw. To begin with, petrol engine-powered chainsaws are noisy and require far more maintenance and servicing than electrically-powered machines. They also require a specialised blend of petrol and oil as their fuel supply which is inconvenient to put together and produces unpleasant fumes when used. The chainsaw fuel also needs to be drained between use if the machine is not used frequently to prevent damage to the carburettor, and if the fuel happens to run out during operation, the chainsaw has to be left to cool down before refuelling in the interests of safety. The weight of the engine in a petrol-powered chainsaw also tends to make the machine much heavier than electric chainsaws, and the need to carry a reservoir of liquid fuel only adds to the weight. Finally since one is buying what is essentially a small vehicle engine, the price point of many-a-petrol-powered chainsaw is higher than it is for electrical equivalents, making them less appealing to the DIYer especially if they are only used occasionally.
The Electric Chainsaw
Given the many disadvantages of the petrol-powered chainsaw, it is perhaps not surprising that amongst DIYers the saw that is more prevalent is the electric chainsaw. The electric chainsaw is generally much quieter and lighter than their petrol-powered equivalents making it easier for just about anybody to handle. The electric chainsaw may lack the power of the petrol chainsaw, but unless one is cutting down large trees regularly, the average DIYer will not need so much power. Electric chainsaws can also be used without worry of generating too much noise which might be important if the chainsaw needs to be used indoors, or in locations at risk of disturbing anyone close by such as the neighbours, and they also do not emit any fumes like petrol-dependent ones. Finally, electric chainsaws are often fitted with safety chains which means that if the chain sticks in the material being cut for any reason, there is less of a chance of a kickback occurring where the chainsaw jumps back at the operator risking injury. The relative lower power of the electrically-powered machines also makes any kickback that does occur less violent.
What to look for when Buying an Electric Chainsaw
Corded vs cordless
As with other power tools, deciding on the type of electrical power system one wants in their chainsaw is one of the first questions to ask when looking to buy one. The decision is one that is based on a number of factors including personal preference, where the machine will be predominantly used, and access to mains power or a universal power tool battery system amongst other criteria.
Cordless battery-powered chainsaws are the least powerful of all the chainsaw types but are probably the most convenient to use as they are relatively lightweight and lack any sort of restricting power cord. This means they are particularly useful in certain situations like when precariously perched up a ladder cutting branches from a tree where they are less tiring use and easier to manoeuvre amongst the branches. On the more negative side, cordless chainsaws tend to be more expensive than their corded brethren and their operation is time-limited by battery capacity.
Corded chainsaws, on the other hand, are more powerful (although not to the level of petrol-based machines) and so are able to handle larger more difficult cutting jobs than cordless ones. They are also generally cheaper than cordless machines and so represent good value for money. On the negative side, however, they tend to be limited in the location in which they can be used due to the need for access to the mains electricity, and the trailing power cord can often get in the way when working.
For corded chainsaws which are measured in Watts (W), the higher the power rating of the machine, the faster it will cut. Therefore, a 2000W machine will cut faster than an 1800W one. For battery-powered machines, the power rating is measured by voltage (V) of the battery which is usually 18V. However, some machines can use 2 batteries at the same time doubling the voltage and allowing these higher voltage battery-powered chainsaw to cut faster and more aggressively than lower voltage ones.
The speed at which the metal chain rotates around the guide bar determines the speed at which chainsaw makes its way through the wood being cut. So a slower chain speed will mean a slower rate of cut whereas a higher chain speed will cut through material more quickly.
Guide Bar Length
The guide bar guides the metal cutting chain of the chainsaw as it rotates. It also determines the chain length and the size of log or other wooded structure that can be cut, so for example if one is only cutting small logs, then a 30cm guide bar should be sufficient. It is also important to remember that the longer the guide bar, the more powerful the machine has to be in order to drive the chain over a greater length of cut.
Tool-less Chain Tensioner
One of the regular maintenance tasks that needs doing when using a chainsaw is to ensure that the tension in the chain is correctly set. This is achieved by adjusting a chain tensioner which is usually in the form of an adjustable screw or a tool-less system on the chainsaw where the tension can be set by the turning of some sort of knob. Obviously for convenience, the tool-less system is the better of the two.
Electric chainsaws are lighter than their petrol counterparts as they have simpler internal working components and don’t have to carry a reservoir of liquid fuel. This makes electric chainsaws much easier to handle and allows their use for extended periods of time without tiring out the operator. Mains-powered chainsaws tend to be slightly heavier than the battery-powered machine mainly due to their greater power output, larger guide bars and longer chains.
Petrol chainsaws are very noisy due to the sound of the internal combustion engine, not unlike those found on road and other petrol-driven vehicles, and can make their use indoors or in residential areas prohibitive. Electric chainsaws, on the other hand, are much quieter and are one of the reasons why they are preferred by DIYers. Corded electric machines tend to be slightly noisier than battery-powered chainsaws mainly due to their greater power output.
Automatic Oil Lubrication
The chain on a chainsaw needs oil to ensure that it always runs smoothly. Application of this oil can be done either manually, or through an automatic oil application system where the oil is stored in an onboard reservoir and automatically dispensed to the chain as it turns. Obviously the automatic oiling system is preferred over having to manually do it oneself, and if the oil tank is transparent helping to better keep track of the oil level, even better!