How to Saw in Cold Weather
By Wood-Mizer, Europe
Whether we like it or not, winter weather is inevitable, but that doesn't mean you have to put the "freeze" on sawing. As colder temperatures arrive and logs begin to freeze, here are helpful tips, reminders, and answers to common questions, to compete with the sawing challenges faced by sawyers this time of year. With the proper sawmill and blade maintenance topics covered below, you can keep sawing like a pro all winter long!
Winter Sawing: 10 Tips for Sawing Frozen Logs
TIP 1: Lower the blade hook angle
Sawing frozen and partially frozen logs or cants can be treated like sawing hardwoods. The best option for frozen wood is the Wood-Mizer Turbo 7 bandsaw blade. This profile utilizes a taller tooth with deeper gullets that are capable of pushing the sawdust out of the cut, resulting in less sawdust on your lumber. The Turbo 7 blade is available in:
- DoubleHard Bandsaw Blades - 1.25” x .045, 1.5” x .045, and 1.5” x .055
- SilverTip Bandsaw Blades - 1.25” x .042, 1.5” x .045, 1.5” x .055, 1.75” x .055 and 2” x .055
- Bi-Metal Bandsaw Blades- 1.25” x .042 and 1.5” x .055
Wood-Mizer 4 and 9 degree blade profiles are also good options for wintry conditions on lower horsepower bandmills that use 1.25” wide bands.
TIP 2: Narrow the blade width
Narrow blades can have less resistance and clean out frozen sawdust more productively. Try a 1 1/4" blade over a 1 1/2" blade in the winter. This can be important with especially higher horsepower engines.
TIP 3: Pay special attention to partially frozen logs
In the early periods of cold weather, more attention may be required when sawing the outer “jacket” boards because logs freeze from the outside in toward the heart. As logs lay through frozen temperatures and long nights, the entire log will be frozen. In the spring as weather begins to warm, logs will also thaw from the outside in. The most difficult time to saw logs is when they are partially frozen because the blade cuts in and out of the frozen material. Sawing partially frozen logs can be done successfully, but will generally require a little slower feed speed in order to monitor each cut.
TIP 4: Keep feed rates up and consistent
Keeping your feed rates up, even while sawing frozen logs, helps clear chips and sawdust out of the cut and keeps them from refreezing on the lumber. Freezing rain, ice, and snow build-up will slow down your machine's warming up process and can affect the life of your mill. For the best results, keep your feed rates consistent and monitor your lumber for quality as it comes off the mill.
TIP 5: Monitor blade guides
Check blade guides frequently and if loose, tighten the guides or replace. Also keep the blade from riding hard against the blade guide flange. It is very important that blade guides are level and not tilted up or down. Use the blade level gauge to check this.
TIP 6: Switch drive and idle side blade guide belts
Periodically swap the drive and idle side blade guide belts and replace as they flatten and wear. This also keeps the blade from riding up against the flange.
TIP 7: Check the blade guide arm
The sliding blade guide arm should be tight and provide the same amount of flange clearance while it’s all the way in or opened. This provides blade stability in the cut.
TIP 8: Use proper blade tension
Sufficient blade tension is essential in sawing frozen wood. Tend to use higher tension if possible and use a blade strain gauge which provides actual tension in blades per square inch (psi).
LT15/LT28/LT35 Sawmills Blade Tension
LT70 Sawmills Blade Tension
TIP 9: Monitor drive belt tension
Do not over or under tension the engine drive belts. Keep them snug and not loose.
LT15/LT28/LT35 Sawmills Manufactured in 2016 or Later Drive Belt Tension
LT15/LT28/LT35 Sawmills Manufactured Before 2016 Drive Belt Tension
LT40/LT50 Sawmills Drive Belt Tension
TIP 10: Change hydraulic fluid
If your cold weather sawing keeps you in a temperature range that stays below 60º F, we recommend running Mobil Aero HFA hydraulic fluid. This will give you faster hydraulics and be less demanding on the electrical system of your mill when sawing during colder temperatures. When temperatures begin to reach 60º F and above, we recommend changing back to all-weather fluid. Make sure all hydraulic cylinders are in the closed position when changing fluid and note that Wood-Mizer standard hydraulic sawmills take one gallon of fluid while Wood-Mizer super hydraulic sawmills require two gallons.
Winter Sawing FAQ
Q: How long should I run the blades during winter sawing?
A: Frozen logs can be treated like extreme hardwoods and may require changing every 1-2 hours of sawing or as frequently as 6-8 logs depending on size and species. It’s better to change bands frequently rather than running them until the tooth tips are rounded. Be sure to use your debarker or remove mud, rocks, etc. from the log bark before sawing. Keeping the logs off the ground when storing and transporting can also assist in keeping logs clean to extend your blade life.
Q: Do I still need to use lubrication on the blade in winter sawing?
A: Yes! Frozen chips or sawdust will heat up during sawing and then refreeze to the lumber or blade. It is always beneficial to keep the blade clean and eliminate any pitch build up on the band that can negatively affect performance, sharp life, and overall flex life. Common additives can include water, our LubeMizer® additive, Pine-Sol, and vegetable oils. Liquids such as windshield solvent or antifreeze can be added to water to keep from freezing. Remember, never add flammable or environmentally unfriendly fuels or liquids.
Q: Do I change anything when sharpening blades?
A: Not really! The most important thing is to bring a fresh, sharp point to the tip of the tooth on both the face and back side. Don’t hesitate to go around the blade a couple times to sharpen the tooth. Use a magnifying glass to evaluate the outside corner of the tooth tip that does the sawing.
Q: Do I need to set the blade each time I resharpen?
A: Most Wood-Mizer tooth profiles offer a sufficient amount of tooth set which allows the bands to cut longer. Lower tooth set can saw with better accuracy and performance in frozen wood. So rather than using set at .025 - .027 it is possible to use .022 - .024 on .045 thick bands and .017 - .019 on .042 thick bands. It is very important that set is even on both sides of the blade. Sawing in frozen wood is also a good time to take advantage of the Wood-Mizer ReSharp® blade sharpening service available at convenient locations throughout the United States.
Winter sawing can be the most demanding for your sawmill. As always, keep your mill well-maintained, aligned properly and covered when not in use. Wood-Mizer sawmill blades are more prepared now than ever for these colder days ahead and now you are too. Follow these cold weather tips and you'll be sawing frozen wood with ease throughout the winter season!