A catalyst for this seems to be Jim Cummings article “Home Shop Bandsaw” in Fine Woodworking #63. From the hundreds of bandsaw owners I’ve talked with since the article appeared, it seems there are lingering questions on how to adjust a bandsaw blade, the blade choice and operation. “To find the correct tension, you can start with the tension scale on your saw, but you will probably need to fine tune the adjustment. With the saw unplugged, increase the tension on the blade until pushing on the side of the blade with your finger using a moderate amount of force deflects the blade about a 1/4” from its normal position. An interesting experiment is to set the side guys too far from the blade and notice how increased feed pressure and turning make the blade wander.
Even a low-end bandsaw blade tension meter can cost $300. If you use your bandsaw a lot or are doing delicate work, having the proper tension on the blade can be critical and the only way to accomplish this is with a bandsaw blade tension meter. With the bandsaw blade properly installed, and tensioned, and the blade guides properly set, the next issue is to make sure that the bandsaw table is square and level. We suggest that you go through the setup steps in this how to set up a bandsaw properly: the ultimate g guide before starting a new project and each time you change your bandsaw blade.
Whether you’re a beginner or could just use a refresher, we’re going to walk you through the process for a perfect bandsaw blade adjustment setup every time, no matter what blade you install. Lower the upper blade guide, open the wheel housing(s) and blade guard and carefully remove the blade. So it should be no real shocker that you’ll encounter conflicting schools of thought regarding blade placement on the wheels and how it affects blade “Drift”.
Install the blade and apply just enough tension to keep the blade securely on the wheels. Instead, tension the blade until your finger is only able to deflect the blade by about 1/4″. This test should be done at the back of the saw where nothing can get in the way of the blade. Adjust the thrust bearings carefully so that they do NOT rotate while the blade moves, but they DO begin to rotate as soon as light pressure is applied to the blade.
Most basic adjustments, including setting the blade guide blocks and thrust bearings and adjusting the tension and tracking of the blade, need to be done each time you change the band saw’s blade. Following this schedule of maintenance and tune-ups helps prevent the saw from developing vibrations and blade wander and keeps your band saw cutting straight and true. If your saw blade wanders during cutting and/or you need to turn the tracking control and tilt the upper wheel excessively in order to track the blade, you should check to see if your saw’s wheels are improperly aligned.
Once the blade has found its natural position, adjust the blade guides so there is no preload on the blade until you start cutting. Plus, I did a quick check- putting the lower blade guide back in place, the blade has to move forward, and by quite a bit. Your other questions have been answered well, it is best if the blade just touches the thrust bearing when fully tensioned and running, this will prevent the blade from jumping back when you start the cut, the side guides should have a small clearance and should be adjusted to the blade after they have all been retracted.
adjusting bandsaw blade guides Related Question:
How far should the blade guides be from the blade of the bandsaw?
Set the front of the blade guide about one-sixteenth of an inch from the deepest part of the blade gullets (the spaces between the teeth on the blade). The blade guides must ride behind the teeth on the bandsaw blade.
How high should the guide be on a band saw?
Make sure the wheels and blade are in good condition. Make sure the blade is positioned properly on the track. Adjust blade guard height to about 3 mm or 1/8 inch to 6mm or 1/4 inch above the top of the material being cut. Wider gaps will place tension on the blade and increase the risk of breaking.
When using a horizontal band saw you should adjust the blade guide as close to the work as possible?
The upper guide and guard should be set as close to the work as possible, at least within 1/4 inch. If the band breaks, immediately shut off the power and stand clear until the machine has stopped. Examine blade before installing to see if it is cracked, do not install a cracked blade.
Why does my bandsaw blade wobble?
The blade on a saw left idle for long periods of time can leave an impression in the rubber tire which might cause erratic tracking. Purchase and install aftermarket replacement tires. (Search for “bandsaw tire” at woodcraft.com.) If you still see a back-and-forth motion, the culprit is probably the wheel itself.
How close do you set the side guides on the band saw?
The front of the side guides should be located about 1/16″ back from the deepest part of the blade gullets. You don’t want the side guides to contact the cutting teeth of the blade since the teeth flare out at a slight angle. This adjustment is made to both the top and bottom guides.
How can you tell if you are using too much pressure or twisting the blade excessively?
you feed the material too hard or twist the material too much, you will hear the saw slow down. This is a cue to ease back the pressure. Too much pressure or twisting can break the blade.
Why does my bandsaw cut to the right?
When the band saw cuts crooked, a dull blade, improper feeding, loose blade tension or not using a work piece guide could be the cause. Use the rip fence or miter gauge to guide the work piece uniformly through the cutting blade to make straight cuts.
Why do bandsaws wander?
Tim Inman: Because band saw blades ride on crowned wheels, they always have a little “camber” angle relative to the vertical axis of the wheel. This causes the blade to tip a little and makes the cut “pull” to the side.
Why does bandsaw not cut straight?
Bandsaw Wheels Aligned Incorrectly or Worn High-speed machines generally have a crown or rounded surface on the blade support wheels, the same way a bicycle tire has a round cross-section. The blade should run at or near the center of the crown and not excessively close to the front or rear edge of the wheel.