Monthly Archives: November 2014
Vickers Hardness Scale
The Rockwell hardness test measures materials hardness based on the net increase in depth of impression as a load is applied. Hardness numbers have no units, and the higher the number in each of the scales, the harder the material. In the Rockwell method of hardness testing, the depth of penetration of an indenter under certain arbitrary test conditions is determined. Hardness is defined as resistance to local penetration, scratching, machining, wear or abrasion, and yielding. The multiplicity of definitions, and corresponding multiplicity of hardness measuring instruments, together with the lack of a fundamental definition indicate that hardness may not be …
Sharpening Saw Blades
Sharpening bandsaw blades is a widely known and acceptable practice in both metal and wood cutting industries. It is applied, however, and almost exclusively, to the woodworking set. A primary problem encountered in the woodworking shop is dull saw blades. Objects encountered while cutting wood include nails, bullets, and other similar materials, all of which will help to dull a saw blade. These extractions from green wood cause damage on the edges of sharp teeth. Dull blade teeth aren’t useful and shouldn’t be utilized. Buying a new saw blade is an option, and so is sharpening the dull blade. There are two ways to …
Bandsaw Newbie-Refresher Course
A preventive safety course for bandsaw operators new to the machines as well as for those quite familiar with them. All bandsaw operators should possess adequate knowledge of mechanics, materials, and most important — safety — prior to any cutting procedure. Lack of experience combined with lack of knowledge will jeopardize not only the materials but the machine and worse, the machine operator. Every bandsaw machine offers various operating features, and before using any particular machine, it is important to be familiar and possess a minimum of confidence prior to operating. Aside from possessing thirty+ years of experience in a variety of shops and …
Feed and Speed Rate Factors
Running saw blades at the correct feed and speed rates is important if the goal is to achieve desirable output. There is an optimum balance between blade speed and feed rate for every saw blade and every material to be cut. Proper adjustment of feed and speed rates will help to maximized blade life and assure a satisfactory cut. Feed rate is determined by the bandsaw, material size and shape, guide spacing, cutting fluid, and tooth size and shape. The greater the blade speed, the greater the feed rate — up to the limits imposed by the above-mentioned production factors. Blade Speed Bandsaw …
Tube Cutting
Cutting tube is more difficult than sawing solid bars. The bandsaw blade is performing two types of cut, sawing solid as it enters the material then entering the hollow tube. The blade is now cutting two thin solids with a space in between — an interrupted cut. To achieve the best result in cutting tube, blade variables and bandsaw settings have to be carefully selected. Tooth pitch (TPI) is an important variable as well. The number of teeth engaged with the material determines both blade performance and durability. A few teeth in contact with the material can lead to stripped teeth, bending, or premature …
Double-Weld Bandsaw Blades
Depending on the needs of our customers, Sawblade.com offers welded-to-length bandsaw blades. This process involves cutting the blade to length, welding it, and then annealing the blade. There are rare instances when a bandsaw blade will have two welds instead of just one. If an order for 16’ of bandsaw blade arrives, and the weld shop only has 10’ of band in stock, the manager may feel confident about permitting an employee to take the 10’ band and weld 6’ more provided it is from the same stock. The weld shop may weigh the potential for problems versus waste and loss. The customer has the right to refuse the …
Making Bandsaw Blades
A bandsaw blade consists of a continuous band of metal with teeth along one edge and used to cut a variety of materials. The band usually rides on two wheels that rotate along the same plane. Some bandsaws may have three or four wheels, depending on the model. The required length of band is cut from a coil and then welded together at both ends. Most weld centers follow the same procedure in creating bandsaw blades. Oil or grease is applied to metals, preventing surface rust. Before the blades are welded, they need to be cleaned using a degreaser agent. …