When cutting metals, there is a lot to be taken into account. The type of blade you are using, speed of cut, configuration & adjustments to your saw should all be looked at thoroughly.
Selecting the proper blade to cut the type of material you are sawing is the first consideration. Aluminum is quite different from mild steel and mild steel is quite different from tool steel etc. For most applications, carbon steel blades are adequate but for the specialty steels, you may have to go for a more sophisticated blade such as a high-speed steel for example.
The recommended cutting speed also varies greatly for the materials that may be cut with this type of machine. For example, some die steels may require a speed of 50-60 FPM, while aluminum can be cut at 10 times that speed. If you select the proper speed it will result in better cuts and a longer blade life.
The configuration of the material and the size of cross section determines the pitch of the blade. If the material is think then a finer pitch is required. If the pitch is too coarse then the material can enter the gullet of the blade tooth and the break the tooth. If the pitch is too fine the gullet will fill up with cuttings before it goes through all the material and will stop the blade from feeding.
Remember to have at least three teeth in contact with the work at all times. The rate of feed is determined by the amount of material that can be carried by the gullets of the saw blade.
For maximum blade life avoid excessive feeds and always enter work slowly at the start of each cut. Keep the saw clean and adjust guides whenever necessary and should get good life from your blades.
Metal cutting band saws usually have the facility to be adjusted to the original settings and will require adjustments occasionally, depending on the frequency of use.
Try the adjustments in the following order.
Remove the blade and clean the drive and idler wheels of all oils and foreign materials. Saws that are capable of using water soluble oils will leave residue on the driving surface of the wheels when the water evaporates, causing the blade to slip off when the saw is under load.
Using the blade as a gauge, check the guide bearings to ensure that they move freely and are not tight on the blade. The blade should be able to slide between the bearings without the bearings rotating when you hold the bearings with your fingers. The bearings are mounted on eccentric shafts and can be adjusted quite readily.
Mount the blade on the machine and check the blade tracking. If the tracking needs adjusting there are usually set screws near the idler wheel axle to change the altitude of the axle, which will use the blade to track either further on the wheel or move off the wheel.
When the blade is tracking properly, adjust the bearing guides to twist the blade into a vertical position. When you do a test cut, you may have to readjust the guides to give a 90° to the blade. When both the vertical and horizontal settings are 90° you should get accurate square cuts. You should select the proper blade and speed setting for the material you are going to cut.
Remember that each time you use your machine the conditions may require some change in the machine. Perhaps a different speed or a different blade. If you make these changes and maintain your machine, you can expect your band saw to operate to its fullest potential.
