Bandsaw Guides and Saw Blade Replacement: blade guide information and the safe replacement of bandsaw blades.
First, a Blade Guide is a small, molded piece of porcelain (generally) which allows a bandsaw blade to track along a consistent path and functions to keep the blade flat on a steady track as it moves with the saw mechanisms.
The guide functions with an adjuster knob, raising the guide up and down to accommodate different material thickness.
Roller Guides are used on small machines, or when blade speeds run over 600 SFPM. They are flat discs, almost like washers, and must retain blade tightness in order to control the band.
Disk Guides are most often used on general purpose, vertical bandsaw machines.
Flat Carbide Sled-type Guides are good for speeds up to about 600 SFPM. Sled guides are better than roller disk types when using high cutting pressure. They spread the cutting force over a larger area, eliminating mushrooming on the back of the blade.
For cutting materials using a bandsaw, this information should help to guide the way.
Second, in order to safely replace a bandsaw blade, effort and patience are required, but by following the correct procedures, that effort can be worthwhile and made simpler as it becomes second-nature to the bandsaw operator’s routine.
Always wear goggles, and be sure to allow for enough time to complete the task — at such a time when there is a minimum of distraction.
Unplug the machine before removing the blade from the bandsaw.
Remove the blade insert and the Pin from the table. To release the blade, loosen the blade guides. To offer ease-of-movement while removing and installing a new blade, loosen the upper ball bearing guide and the upper blocks. The right and left block guides must be loosened along with the rear and front guides.
The use of an adjustment knob will help to make this procedure easier.
Next, release the tension on the blade by using the tension knob (which is commonly found at the top of the band saw). You should be able to pull the blade off from the top wheels. After the blade is removed, make sure to recoil and tie the blade to avoid any damage.
Steps for beginning bandsaw blade replacement
- Make sure uncoiling a new blade is a familiar procedure
- Hold the blade firmly in both hands, with the teeth facing away from the body
- The lower part of the blade should be placed forward of the operator and be pressing against a fixed object – a foot is acceptable if possessing experience at uncoiling a blade
- The blade should then be pushed forward while turning the hands inward (this will cause the band to overlap immediately in front of the hands)
- At this point, the blade can be held in one hand, allowing the free hand to lift the lower part of the blade into the coil of the rest of the blade (the flexible nature of the blade will cause it to form a coil)
Opening the new bandsaw blade can be dangerous if not paying attention and not respecting that a saw blade is a sharp implement.
The next series of steps to take include:
- Wear gloves
- Take the blade in one hand and remove the twist ties with the other hand
- With the band hanging vertically, rotate the blade in both hands, separating the three loops to find the loose middle loop
- Using the hand holding only one loop, grasp the loose middle loop
- Keep hold of these two loops and while also holding the blade away from the body, remove your free hand
- Separate the band by taking one loop in each hand and allow the band to spring open under controlled pressure
Installing the new blade
- Slide the blade back through the slots of the table and place the blade on top of the upper wheel.
- Hold the blade until the tension of the blade can hold itself on the wheel.
- Using the tension knob, apply tension to the new blade.
- Apply tension according to the blade width.
- You can also try plucking the blade to determine if it is the proper tension of your blade.
Track your blade
Once you’ve applied proper tension, your blade needs to be tracked or centered. Using the tracking knob on the side of the band saw, push the blade on the center of the band wheels. Turn the tracking knob with one hand while using the other to turn the wheel, in order to properly track.
Returning the guides
Return the blade guides, the roller, and the block guides. The bearing should have a little space for your blade. You can use a one dollar bill or any paper with the same thickness to insure that the spacing is correct.
Test your blade
The band saw is almost ready for use. The last step is to test if the blade is properly inserted.
- Plug your saw back in and turn on the machine
- Observe the blade
- If the blade vibrates or falls off the center, check tension and tracking again
- Repeat procedure until the blade runs smoothly
These are the basic steps I’ve followed while replacing my band saw blade. If you know of other methods to replace a band saw blade, post your methods on our blog. We’d love to hear from you.