General Filing Operations.

(9) Annealing the Welded Band. Directly above the grinding wheel is the

annealing pushbutton.

When the band is heated up in the welding and

grinding process, the steel at the point of the weld air-hardens and is

brittle. Therefore, it is necessary to anneal the weld by reheating it and

allowing it to cool slowly.

This returns the band to an approximation of

its original temper. Use these steps to anneal the weld:

(a) Clean the welder jaws.

(b) Press the spring clip behind the weld lever, and move the lever up

all the way.

(c) Clamp the band just back of the teeth.

(d) Set the ANNEAL HEAT selector switch (refer to figure 24 on page 32)

at either the 1/16 inch to 1/2 inch or the 5/8 inch to 3/4 inch position,

according to the width of the blade being annealed.

(e) The next step in the annealing process depends on the type of blade

being annealed. It is very important that this step be performed carefully:

1 Carbon Blades. If a carbon blade is being annealed, press and jog

the anneal switch pushbutton until the weld is a dull cherry to cherry red

in color.

Then allow the blade to cool slowly by decreasing the jogging

2 Dart Blades.

For a Dart blade, heat the blade slowly until the weld

becomes a deep blue

color. Continue to heat by jogging the anneal switch

pushbutton until the

width of the blue color is one-half the length of the

band exposed between

the jaws. Do not overheat or the temper of the band

adjacent to the weld

will be damaged. Cool quickly by releasing the button.

e. General Filing Operations. Filing operations are performed on the

bandsaw machine using a band file and the band file attachment.

As with

sawing operations, the quality of filing and the economical wear of the band

file depend upon proper selection of files and filing speeds for different

materials and conditions.

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