How to Replace the Lower Wheel on a Jet Band Saw
Finish Nailer Repair - Replacing the Driver Guide (Ridgid Part # 79004001022)
The lower wheel drives the band saw's blade. The wheel is made of cast aluminum, and is machined to attach to the driveshaft and to accept the tire. The wheel is factory-balanced to ensure smooth operation. The wheel is mostly trouble-free (rarely requiring maintenance). However, the lower wheel can become damaged if the bolt that secures it to the drive shaft becomes loose. This can allow "play" in the wheel (leading to vibration, wear, and failure).
Because the wheel is cast metal, it can also become warped. Symptoms of a warped wheel are difficulty tracking or centering the blade on the wheel. If this occurs, the lower wheel should be replaced.
Let's get started.
REMOVING THE LOWER WHEEL
1. Remove the blade.
Remove the table alignment pin.
Remove the table insert.
Loosen the blade tension.
Open the wheel covers (doors).
Remove the blade from the upper and lower wheel assemblies.
Slide the blade through the slot on the table and away from the saw.
2. Remove the lower wheel.
Remove the bolt securing the lower wheel to the drive shaft. (The bolt is REVERSE-THREADED, which requires CLOCKWISE rotation for removal.)
Pull the wheel away from the shaft.
INSPECTING THE TIRE
3. Inspect the tire on the old wheel.
If the tire is in good condition, you may want to transfer it to the new wheel. If the tire is hardened, damaged, or cracked, you will want to replace it.
To remove the tire: Use a pair of flat-blade screwdrivers to carefully pry the tire away from of the old wheel.
To install the tire on the new wheel: Align the bottom half of the tire with the bottom half of the new wheel and carefully begin stretching the tire into the groove surrounding the wheel.
Continue stretching the tire onto the upper portion of the wheel, using the screwdrivers for leverage. (Be careful not to damage or cut the tire).
Verify that the tire is smoothly seated (in the groove) around the entire wheel.
INSTALLING THE NEW LOWER WHEEL
4. Install the lower wheel.
Align the key on the drive shaft with the keyway in the new wheel.
Slide the new lower wheel onto the shaft. (The side of the wheel with the recessed hub should face outward.)
Secure the lower wheel with the bolt. (Again, this bolt is REVERSE-THREADED, which requires COUNTERCLOCKWISE rotation for installation.)
REASSEMBLING THE UNIT
5. Reinstall the blade.
Guide the blade through the slot in the table, and through the blade guides.
Fit the blade over the (wheel) tires.
Tension the blade.
Verify that the blade is properly aligned by rotating the wheels.
Close the upper and lower blade covers (doors).
Install the table insert.
Install the table alignment pin.
