How To Change a Sawmill Bandsaw Blade

Replacing a used or blunt blade on your Wood-Mizer sawmill is a necessary part of the sawmill’s daily maintenance schedule, even more so if the sawmill runs each day.  
Wood-Mizer recommends that the blade is changed every 1.5 hours (1h:30min) to maintain optimal cutting performance.

However, this blade change time is not set in stone and can vary or change due to a number of reasons: 

Condition of the log:

• If the log is dirty (caked with mud, wedged-in-bark stones) and not debarked (bark still attached) 
• Cutting dirty (caked with mud, wedged-in-bark) or logs with bark will require more frequent change when compared with cutting clean logs (dirt removed and debarked).
• Industry practice is to debark logs or if debarking is not done to at least remove as much dirt as possible to reduce the wear on blades.

Timber type and structure:

• Hardwood tends to be denser and harder than softwoods although there are exceptions. Cutting harder and denser timber can impact on how frequently the blade is changed.
• Some timber species have sand (silica) deposits that are part of the timber’s internal structure. Cutting timber with a high silica content can blunt or wear the blade down faster.  

Blade quality:

• Higher quality blades generally last longer, but even those need replacement with the recommended blade change interval a good time to inspect the blade for wear.

Signs of a worn blade:

• A handy list of what to check for in general to determine the wear of a blade includes
• Noticeable decrease in cutting speed.
• Increased vibration.
• Uneven or wavy cuts.
• Excessive heating.

How to change a blade

Changing sawmill blades is safest when done by one person. 

Remember to always disengage the blade and shut off the sawmill engine before changing the blade. In addition, wear gloves and eye protection while keeping others at a safe distance when handling sawmill blades.

Step 1:
Turn the blade tension handle until the wheel is pulled in and the blade is loose in the blade housing

Step 2:
Open both blade housing covers.

Step 3:
Lift the blade out of the blade housing.

Step 4:
Install the new blade while making sure the teeth are pointing in the correct direction. The teeth should be pointing towards the sawdust discharge chute of the sawmill.

Step 5:
Position blade on the wheels so the gullet is 3mm out from the edge of the blade wheel.

Step 6:
Close the blade housing covers.

Step 7:
Use the tension handle to tension the sawmill blade correctly.