Winter milling can be a challenge for both the sawyer and the machine. While staying warm is important for the operator, this article will focus more on the portable sawmill side of the equation. The interaction between man and machine can get more complex and, in some cases, more dangerous when the thermometer dips below the freezing point. And naturally, the colder the temperature, the greater the challenge.
Ice is your biggest enemy, especially when it is under your feet. For example, the biggest cause of injuries to log skidder drivers is slipping on the step up to the cab. Be diligent about keeping ice off the steps of your loader or tractor. The ice on the ground is, of course, another matter. One trick I’ve learned is to keep a can of wood ash to throw under the tires for traction (the ashes, not the can!). It is amazing how well it can get you moving. Tire chains grip into ice, snow and mud when nothing else will. They are also available for nearly any size tractor or ATV tire.

On the mill, ice presents a whole different set of problems. You won’t get consistent cuts if there is ice on the tracks. Keep the mill covered, if it isn’t in a shed. Control cables have a nasty habit of freezing up. Even if they are covered, moisture can condense on the cable inside the housing. You can prevent this by occasionally spraying silicone lube into the housing. Moisture can also condense in the fuel tank, blocking the flow when it freezes. If this is an issue, adding “dry gas” (methanol) to the fuel is your best bet. To keep your blade lube in liquid form, mix in -40 degree windshield washer fluid. This is where it pays to have an automatic shut-off on a portable bandsaw mill so you don’t waste lube when you’re not cutting! You might still want to add pine-sol, simple green or other blade cleaner/lubricants to the mix.
Half-frozen logs actually present more of a challenge than logs, which are frozen solid. As the tooth of the blade travels through areas of frozen, then softer wood, it may tend to wander a bit, much as it does when cutting through a knot. Increasing the blade set from .024 to .026” and slowing down the feed rate will help give straighter cuts. You may also find the sawmill blades need changing more frequently, since ice crystals are somewhat abrasive. It may help to drive clamps in with a hammer to get it through the frozen wood for a solid grip on the log. If a log has been on the ground, it will probably have dirt frozen to it which could make short work of your blade, so try clean ahead of the saw cut if the log is dirty or do your best to remove the frozen debris before you start cutting. In extreme cold, boards will freeze back to the cant after they have been cut. It may take a heavy hammer or even wedges to break them free. Finally, keep the blade moving once you start a cut. The last thing you need is a blade frozen in the log!
Synthetic lubricants are a big plus in cold weather. Run the lowest viscosity recommended for your engine (generally 5W40) in cold weather. It may be a little more expensive, but it will make the engine easier to start. If you use a battery start on your mill, have an extra battery and a set of jumper cables to assist on the coldest days. Cold weather reduces the cranking power of the battery and it has more work to do as it churns the engine through the cold oil—it will likely need a little help. A good shot of starting fluid in the air intake may help bring the engine to life. Once it starts, give it a little extra time to warm up before you start cutting. Your mill’s engine may have optional cold weather parts or recommend a carburetor adjustment to compensate for the denser cold air.
Portable sawmills with hydraulics tend to slow down in cold weather. While you should always use approved hydraulic fluid, there may be a recommended cold weather hydraulic fluid designed to work more effectively. Automatic transmission fluid works well in cold weather for many applications, such as log splitters. As with your engine, be sure to give your hydraulics time to warm up. There are cold-weather chain saw oils designed to flow better in sub-freezing temperatures or mixing in 5{ecddf9adde44d27d9b15adaf662c1dc75823d7a27d1c0a3dca6c68c19970fb5c} diesel fuel thins out chain saw oil to keep it flowing. As always, the best practice is to use a tank of oil at about the same rate as you use a tank of fuel.
But let’s not forget the all-important operator. Don’t ignore your own comfort and safety. It is hard to work and use good judgment when your fingers are numb from the cold so ensure you have a good set of gloves and maybe even invest in disposable hand warmers for particularly chilly days. Always have a means of communication in case you need help or should an accident occur. If your cell phone or walkie-talkie has problems with the cold, keep it under your coat so that it stays warm enough to operate. A couple of hand warmers placed strategically under your coat can also help keep you warm on the outside and a thermos of a hot beverage (non-alcoholic since you are operating equipment!) can help to keep your insides warm. Alcohol, by the way is a triple threat in cold weather. Not only does it affect judgment, it also dilates your blood vessels, so you lose body heat more quickly and absorbs water thus contributing to dehydration. So save the drink until after you’re done working.
Finally, be careful in cold weather. If either you or the equipment aren’t working properly, just ask yourself, “How important is it, in the grand scheme of things, to cut that log today?”