They have more names than you can imagine: Dog teeth, bucking spikes, bumper spikes, felling dogs, dawgs, you name it. Whatever you prefer to call them, they are the series of spikes that can be found on a chainsaw at the back of the bar. For some, these dogs are a nuisance and removed immediately. For others, they are a helpful tool to aid in woods work, but are these chainsaw dog teeth truly necessary? While they are an optional feature on a chainsaw, felling dogs provide a great deal of stability and leverage for the sawyer by providing an anchor point for the saw. This can be particularly advantageous when working with larger diameter logs or when cutting continuously for long periods, such as when cutting firewood. However, they do have a few disadvantages. Let’s dig in to felling dogs to understand their purpose and limitations so you can decide whether or not they’ll work for you.
What Felling Dogs Are Used For
We may take it for granted, but chainsaws are extremely powerful machines with a tremendous energy output. Especially when they are larger, controlling this energy can be a bit difficult. As the saw’s engine spool’s faster, the momentum causes the bar to rise, and if the tip of the chainsaw hits something, it can cause kickback. This is where felling dogs come in.
Felling dogs give the sawyer the ability to anchor the chainsaw into the tree or log itself, thus allowing for a tremendous amount of control and precision in a cut. Using the felling dogs as an anchored fulcrum, the chainsaw can be levered so the sawyer can cut more aggressively without having to put much pressure on the saw itself. Because of the extra control, felling dogs also add an element of safety for the operator, as it reduces the chance of kickback any uncontrolled outcomes. Of course, even with dogs, operators require much more safety gear.
When Do Felling Dogs Really Come in Handy?
There are two situations when felling dogs on a chainsaw are particularly advantageous:
- Felling and bucking large diameter logs.
- Continuous cutting activities, such as bucking firewood.
The advantage felling dogs have for larger diameter logs is clear. As logs get larger in diameter, the pressure the sawyer puts on the saw is distributed across greater area, thus reducing the pressure per square inch. Combined with the natural rise of a chainsaw in motion, this can greatly slow down cuts and exhaust the operator as more pressure is needed to get the saw to cut. By anchoring the saw with felling dogs and using it as a fulcrum to lever the saw, the operator can more consistently and easily apply pressure, allowing the saw to do most of the work.
Likewise, the same principle can be used to greatly reduce the total workload and fatigue from operations that require cutting on a more or less continuous basis, such as cutting firewood. fatigue is cumulative. Even if the size of logs is small, cutting a thousand times will take its toll, and so it is important to make every cut as easy as possible. by using the bottom of the felling dogs to bear into the log and lever the bar through the cut, the sawyer can cut through a whole cord of wood like butter. It makes cutting firewood and bucking logs an easy task, which is why some people call these teeth “bucking spikes.”
What Are the Disadvantages?
There are two main disadvantages of felling dogs:
- Reduced usable bar length.
- Additional space for small sticks and brush to get caught.
Equipping your chainsaw with felling dogs does slightly reduce the length of the bar that can be used for cutting, but this can be mitigated by using the proper size teeth, which we will discuss later. This is mostly a minor inconvenience compared to the benefits of the dogs, however.
The largest disadvantage from felling dogs comes from the fact that it provides an area that small, loose sticks and brush can get caught in as the chain pulls the material toward the dogs. This is a major consideration if you do a lot of yardwork with saws, which is why many smaller homeowner chainsaws come stock without felling dogs. It may also be a consideration if you work with a lot of smaller material, such as cutting up slab wood for firewood.
Consider these disadvantages when determining whether or not you wish to use them.
What Size Teeth Should I Use?
There are generally two types of felling dogs that can be used: those with small teeth, and those with larger, more aggressive teeth. Which type one should use largely depends on what one plans to cut.
The larger teeth are mostly used for larger trees with thicker, softer bark, such as cedars and pines. The long teeth allow the saw to sink into the bark and and make the cut without slipping. By sticking out further, they can also give the sawyer slightly more leverage over the cut, which can help with larger logs.
Smaller teeth, on the other hand, are more suitable for smaller trees and trees with thinner, tougher bark. If the bark on the tree is thin and/or difficult to penetrate, larger dogs will simply yield no benefit, so it it better to have shorter teeth to keep more of the bar exposed and usable. Spruce, as you can see in the image below, has extremely thin bark. Regardless of how long the teeth are, felling dogs will be unable to grip into this spruce more than a quarter of an inch.
When deciding what size felling dogs to use, one should also consider bar length. As mentioned previously, felling dogs come at the disadvantage of losing some of the bar length. Longer teeth will cover more of the bar. For this reason, if you are going to use larger teeth, it is best to have a chainsaw bar that is 20″ or longer, otherwise too much of the bar is covered. Shorter bars are better suited for shorter teeth.
Should I Use Single or Dual Felling Dogs?
Dual felling dogs on a chainsaw (one on each side of the bar) will undoubtedly enhance the grip and control provided to the sawyer. However, not all chainsaws are designed to be equipped with two dogs. If the manufacturer did not intend the model of chainsaw to be fitted with two dogs, it will be unable to be fitted with them without heavy modification. It is best to check your chainsaw’s user manual to see what can work with your model.
Whether or Not to Equip Felling Dogs Is up to You
Felling dogs come with great advantages when felling trees or bucking logs, but they are ultimately an optional piece of equipment. Whether or not you use them depends on you and your situation, so hopefully this article helped you understand their advantages and disadvantages and hopefully clarified the decision for you. Personally, I love them, and all practicality aside, I think they look really cool!