Band Saw Tires Snapping

[Craig Colvin]

I have an 18" Jet Band Saw and the top tire keeps breaking in two. I've had 3 tires break in the past 2 weeks. Prior to that it had gone 2 years without a problem with the tire. I can't figure out why they keep breaking.

Here's the things I've tried
- Changed the blade
- Decreased the blade tension
- Increased the blade tension
- Checked the wheel for burrs or sharp edges
- Checked and rechecked the tracking, and bearing positions
- Cleaned the bearings and replaced a couple of frozen ones

Any ideas of what to try next? I'm out of ideas.

[Sam Yerardi]

Some things I would check:

Make sure a string line draped over the face of the top wheel is plumb and flush with the face of the bottom wheel. Make sure both wheels are not out of angular position with each other. There will be some granted for wheel tracking but it shouldn't be major.

Check the inside of the blade to make sure it is smooth and not cutting the tire.

Unplug the saw. With a blade installed with one of the tires (temporarily) in place under less than or equal to normal pressure, slowly rotate the tires throughout the circumference of the enitre blade. As you do this, pick the back of the blade as you would a guitar string. The pitch should not vary much at all as the wheel rotate. If it does that is telling you that something is out of round. If the original tire was not a problme but subsequent ones are, I would start to think that maybe the original tire might have compensated for the wheel being out of round, but new tires won't because they're not in the right place rotationally on the wheel. Just a wild guess but it is worth looking at.

Make sure there is no dust, etc., under any of the tension spring adjustments. if here is, it might cause you to over-tighten while indicating proper tension but it's way too tight. You blade may be strong enough to withstand that but the tire may not be able to.

If the tire is creeping (for whatever reason) while it is installed and turning, you may have to use rubber glue to hold it in place. I have had to do that before just for a tire coming off. if it is creeping it would easily pulll itself right into the blade allowing it to sever it.