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!
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 - 32x1,14 mm, 38x1,14 mm, 38x1,4 mm
- SilverTIP Bandsaw Blades - 32x1,07 mm, 38x1,14 mm, 38x1,4 mm, 45x1,4 mm, 50x1,4 mm
- Bi-METAL Bandsaw Blades - 32x1,07 mm, 38x1,4 mm
Wood-Mizer 4 and 9 degree blade profiles are also good options for wintry conditions on lower horsepower bandmills that use 32 mm wide bands.
TIP 2: Narrow the blade width
Narrow blades can have less resistance and clean out frozen sawdust more productively. Try a 32 mm wide blade over a 38 mm wide blade in the winter. This can be important with especially lower 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 and adjusting the setting of teeth.
TIP 4: 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. Refer to the user’s manual to make the necessary adjustments.
TIP 5: 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 6: 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 7: 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).
TIP 8: Monitor drive belt tension
Do not over or under tension the engine drive belts. Keep them snug and not loose.
TIP 9: Change hydraulic fluid
If your cold weather sawing keeps you in a temperature range that stays below -15°C, 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 -15°C and above, we recommend changing back to all-weather fluid. Make sure all hydraulic cylinders are in the closed position when changing fluid. If you use Mobil DTE 10 hydraulic fluid, you don’t need to exchange it, because it works well in every weather.
Winter Sawing Frequently Asked Questions
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 two or three times to sharpen the tooth.
Q: Do I need to set the blade each time I resharpen?
A: Yes, we recommend checking the tooth setting after each resharp operation. During sawmilling of frozen wood, it recommended also to decrease the setting, on average by two units on the setter scale.
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!