Portable Bandsaw Timbermill & Sawmill Blade Tracking

• Old Talgai PTY LTD

BLADE TRACKING

In this post we will speak about portable sawmill blade tracking and its importance on obtaining the best cut your portable sawmill can achieve.

Blade tracking is the fine-tuning of the band wheel angles to “hold” the blade during cutting. This “hold” position maintains the blade’s location during most sawing conditions, with the guide bearings and blocks acting as occasional supports. A properly tracked sawmill will hold the

band portion of the blade centered on the belts without any guides in contact with the blade.

This image shows the “ideal position” with the blade band centered on the belts & band wheels.

Precise measurements are not required to center the blade band with the belts & band wheels. Visually confirming the front and back of the blade overhang a similar amount is adequate.

What Happens when Tracking is “Off?”

‣ Excessive blade guide bearing wear

‣ Wavy cuts caused by uneven tension within the blade

‣ Overheating blades / blade breakage

‣ Excessive belt wear

‣ Blade will not stay on the belts

Important Points:

‣ Tracking testing can only be made with a blade installed.

‣ Tracking testing is done under full blade tension. A fully tensioned blade is when the

tension handle is snugged to the thrust bearing and then rotated a further 2-½ to 3 full turns.

‣ Tracking adjustments are made at three (3) turns off full blade tension.

‣ The blade should run in the same location on both the follower and drive-side belts.

‣ Guide assemblies should always be pushed all the way back, clear of the back of the

blade. Nothing should ever be in contact with the blade when testing or making tracking adjustments.

‣ The following test and adjustments should only be attempted with drive and follower belts

that are in good repair and keeping the blade up off the cast iron band wheels.

‣ Tuning the blade tracking is a process of testing and adjusting—re-testing and adjusting—

re-testing and adjusting. The number of cycles is determined by how far off the tracking was at the start of the process.

‣ Please see the following pages for testing and adjustment procedures.

TEST PROCEDURE

1. Always wear safety gloves and eyewear. Never attempt to adjust the blade tracking with

the engine running. Remove the spark plug cap as a safety precaution.

2. Loosen the blade guide assemblies, push them back as far as possible, and secure.

This will ensure the guide blocks and bearings will not touch the blade during the test.

3. Install a blade if one is not already installed.

4. Fully tension the blade by snugging the tension handle to the thrust bearing and rotate it

a further 2-½ to 3 full turns.

5. Start rotating the band wheels by hand in the direction of cut observing how the blade

moves forward or rearward on the belts to find its “hold” position.

**If the blade looks as if it is going to come off during hand rotations—STOP—and

proceed to the Follower-Side or Drive-Side Adjustment as required.**

Important Points Before Making Adjustments:

‣ Start adjusting the side that is furthest out of spec first.

‣ Since adjustments made to one side can affect the other side, always adjust one side

first, rerun this test procedure, then adjust the other side if needed.

‣ Because ¼ turn adjustment increments are recommended, it is common to run this test a few times between multiple adjustments before correct tracking is achieved.

FOLLOWER-SIDE ADJUSTMENT

1. Back off the blade from full tension by three (3) full turns of the tension handle.

**Ensure blade guides are still pushed back

and clear of the blade.**

2. Adjust the blade position:

3. Repeat the Test Procedure to see if further adjustment is needed.

4. Repeat the follower-side adjustment steps and test procedure as many times as necessary until the blade is tracking properly.

DRIVE-SIDE ADJUSTMENT

1. Back off the blade from full tension by three (3) full turns of the tension handle.

**Ensure blade guides are still pushed back

and clear of the blade.**

2. Loosen the jam nut Ⓐ on the upper bolt.

3. Loosen the upper bolt Ⓑ ½ turn.

4. Adjust the blade position:

5. Re-tighten the upper bolt Ⓑ followed by the upper jam nut Ⓐ.

6. Repeat the Test Procedure to see if further adjustment is needed.

7. Repeat the drive-side adjustment steps and test procedure as many times as necessary

until the blade is tracking properly.

TRACKING RUN-IN

Once the band wheel angles have been tuned and the blade’s “hold” position is correct as per

the test procedure:

1. Fully tension the blade by snugging the tension handle to the thrust bearing and rotate it

a further 2-½ to 3 full turns.

2. Disable lubrication by closing the valve on the tank.

3. Close and latch the band wheel housing doors.

4. Start the engine.

5. Take the engine slowly up to half throttle for fifteen (15) seconds, then full throttle for an

additional fifteen (15) seconds, and then turn the engine off and wait for the blade to stop

spinning.

6. Open the band wheel housing doors and confirm the tracking settings have held.

7. Bring the guides forward into place and set as per the following the blade guide adjustment procedure.

To summarize blade tracking is the precise adjustment of band wheel angles to maintain the proper position of the portable sawmill blade during cutting. A well-tracked sawmill holds the blade centered on the belts without any guides touching it. Incorrect tracking can lead to issues like blade wear, wavy cuts, overheating, and belt damage. Adjustments are made under no blade tension, and a testing procedure is followed to ensure accurate tracking. By carefully adjusting the follower and drive-side, the blade can be aligned correctly. Once the tracking is set, a run-in process is performed to confirm the adjustments. Proper blade tracking is crucial for optimal sawmill performance and longevity.