Video: How To Change A Band Saw Blade
Using the correct blade and keeping a sharp blade in your band saw are two of the best ways to get good cutting results. Learn how to change your band saw blade and how to set your band saw guide blocks and thrust bearing.
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Video: How To Change A Band Saw Blade - Video Transcript
Speaker: Today, I’m going to walk you through the process of changing a band saw blade. It’s pretty simple, but there are three main things to consider: blade tracking, blade tension, and guide adjustment. Before we get started, make sure saw is unplugged.
A band saw has two guide assemblies. What these do is they keep the blade from twisting and flexing while you’re making a cut. There’s one guide assembly above the table, and there’s another one that’s nearly identical below the table. We need to loosen these before removing the blade.
We’ll start by removing the guide blocks. There are lots of guide block styles. This saw has ceramic blocks. Others will have metal blocks, or roller bearings like this one. This saw has knobs that loosen up, so you can pull them away. Your saw may require a wrench. If you’re unsure how to do it, just refer to your owner’s manual. Once those are pulled away from the blade, we can loosen up the whole assembly and slide that free. Now, repeat this process on the lower guide assembly.
Next, I’m going to raise the blade guard and guide assembly so I can get at throat plate to remove it. A lot of saws just have a throat plate that sets in place. This one is secured with a screw. We’re almost ready to take the blade off. One more step. Since the blade is a continuous loop, the table is slotted so that you can get the blade out. At the end of the slot, there’s either a pin or a bolt that keeps the halves of the table in alignment. We have to take that out.
Now we’re ready to remove the blade. First, I’m going to open up the access doors and the blade guard, then I’m going to release the tension. This saw has a quick release lever on the back. A lot of saws are not going to have that, so you’d just have to release the tension manually by turning wheel. With the tension released, I’m going to take the blade off of the top wheel, work it out of the guards, turn it 90 degrees and slide it out of the slot.
Before we put the new blade on, this is the perfect time to check the rubber tires on the wheels and clean off any saw dust or debris. You can use a brush, or if there’s debris on there that’s kind of stuck, you can use a metal scraper or the edge of the steel ruler. Just don’t use any solvents.
To install the new blade, we’re just going to reverse the process. Start by sliding this through the slot. I’ll guide the blade into the guards, and roughly center it on both wheels. Now, we’re going to retention the blade and adjust the tracking. An important thing to remember here is that the wider the blade, the more tension you need. We’re going from 1/2-inch blade to 1/4-inch blade, so before reengaging the tension I’ve already significantly backed off the tension using the wheel, so that when I do reengage this lever, it’s not too tight.
Now, I can turn the wheel by hand and check the tracking. Slowly turn the wheel and watch how the blade tracks. If it starts to drift off of center, use the tracking knob to move the blade back to center. Once the blade stays centered for several revolutions, you’re ready to apply final tension. Most band saws will have some form of tension scale, either inside the housing like this one around the back, and it’s based on the width of the blade. What I’ll do is turn the blade tension hand wheel until I’m close. Then the final test, I’ll flex the blade with my finger using just light pressure. I should be able to move it about 1/4 of an inch.
Now, we’ve got the tension set and our saw is tracking properly. Now we need to reset the guides. First, I’m going to lower the assembly down to within a few inches over the top of the table. Adjust the thrust bearing so that it’s about 1/32 of an inch behind the blade, and then tighten it. Then slide the guide assembly forward until it’s just behind the gullets on the blade’s teeth, and tighten it in place.
Start with one guide, and slide it so that it just touches the blade and then tighten the set screw or knob. Do the same with the other guide, making sure that the guides don’t pinch or deflect the blade. Repeat the procedure on the lower guide assembly. Finally, I’m going to reinstall the throat plate and then the table alignment bolt, and I’m ready to cut. Remember, the most important thing is to keep a sharp blade in your saw. When you’re changing the blade, remember tracking, tension, and guide block set up, and you’ll have great results.