A Guide to Band Saw Tune-Up.
Tuning the band saw is a necessary evil if perfection of cut, smoothness of materials, and pride in workmanship are the desired end-result of any work effort.
The band saw machine is an important tool for woodworkers. Few things are more satisfying than re-sawing thin sheets of veneer out of a large piece of wood. The band saw is essential for cutting such curves and for re-sawing veneers. In order for these results to be achieved, the band saw in use must be tuned correctly or the re-sawing will become difficult.
There are four primary steps to help you optimize the band saw blade’s capability. This is necessary and should be done with every new blade.
- Check the blade tension
- Properly align the blade
- Check the blade for square
- Set the guides
When installing a band saw blade, one of the very first things to do is measure the tension of the blade while it is on the band wheels. It is better to check it manually. Depending exclusively on the gauges may not give as accurate a read.
To manually check the tension, tighten the blade, flick it with a finger, or pluck it. The blade will produce a tone that should sound clear rather than wobbly. By wobbly: like the sound you hear just by shaking the blade.
Many experienced operators recommend a slight over-tension of the blade in order to achieve a better cut. This can be problematic, however. A blade can take a little more tension than the gauges recommend, but it is not always a good idea. Over-tension might cause the saw’s bearings to fail. If the band saw is not going to be used for a long period, that over-tension of the blade on the saw can cause flat spots on the tires. New tires will be necessary in order to fix the acquired vibration problem. Replacing a tire, especially rubber tires, can be difficult and messy.
When properly aligning a blade, the blade should then run in the middle of the wheels. The idler wheel should be balanced with the drive wheel. Spin the wheels by hand, and then adjust the tracking control until the blade is running in the center of the idler wheel. If it is already centered, lock the control in that position. Cover the wheel and turn the machine on at 50%. Check the blade to determine if it is in the correct alignment.
Always make sure to have it in proper alignment before going up to full speed.
Check the blade for square
One of the oldest tricks in woodworking is a simple method for determining when any assembly or item is square. It is based on the Pythagorean Theorem, which states “The sum of the squares of two sides of a right triangle is equal to the third side, or the hypotenuse.”
Level the table, square the table to the blade, and then lock it in place.
Set the guides
Most band saw machines have two similar sets of guides. One set above the table and the other set below the top guides. Your machine may also have a guide bearing and two block guides, or a guide bearing and two side bearings.
Back bearings resist the force when you push the board through the blade while block guides prevent the blade from twisting out of position
If there are problems with the way the blade is cutting after this tune-up, the saw may require a more involved adjustment. There may be a problem with wheel alignment, wheel balance, or an adjustment of the drive train.
The owner’s manual will be better able to assist with such problems.
Make sure to carefully read the Operator’s Manual. There are many fine adjustments necessary in order for the band saw to cut properly. Failure to follow the instructions will decrease the machine’s performance and will likely cause blade breakage.
Following these guidelines for tune-up of a band saw machine will help to achieve the optimum capability of the band saw and saw blades.