5. Sawing

• Basically a saw drags a number of cutting teeth through work to cut a thin slot. When done, two major piece can be separated.

• The basic saw blade look like,

 

• Saw types,

Circular saws: use round blades rotated at high speeds.

Band saw: a band is in one continuous loop-, like a ribbon.

Hack saw: a small blade much like a steel ruler. This is moved back and forth (it reciprocates) to provide the cutting action.

• Saw operations include,

Cutoff: one smaller piece of stock is cut from a larger one.

Contouring: a band saw is used to cut a non-straight path in an object, often this step precedes other machining operations, such as drilling.

Stack Cutting: multiple pieces are cut at the same time.

Shaping: Chunks are cut out of a larger piece.

Angular Cuts: such as cutting a side hole in a pipe.

Internal Cuts: the entire hole is enclosed in the material.

Ripping: Long cuts to separate parts into halves.

5.1 Problems

Problem 5.1 A 1/2” thick steel plate is being cut on a band saw. The saw blade has 10 teeth/in. and with a feed rate of 0.002”/tooth and is traveling at 200 fpm. How many inches per minute may be cut?

Problem 5.2 When sawing, how many teeth of the blade are cutting at any time?