Johnson Hardware V-24, VH-24, E-16, V-40, VH-40, V-16, Johnson Vertical Band Saws 29/03

4/29/03

Note: Occasionally the drive wheel may have to be jogged by hand to engage the transmission lever.

The variable speed is achieved through the use of a variable regulator. (Figure 3) This is turned clockwise or counter clockwise to obtain an increase or decrease in blade speed, in either range. Adjust until desired speed is reached as read on the blade speed gauge. (Figure 4)

WARNING: DO NOT ADJUST THE VARIABLE SPEED

CONTROL (FIGURE 3) SPEED UNLESS THE MACHINE IS IN

OPERATION! FAILURE TO DO SO WILL CAUSE SEALS TO

FAIL, AND RENDER THE UNIT INOPERABLE.

SAW BLADE SELECTION

There are numerous types of saw blades available depending upon the application. Tooth pitch, form, tooth set, and blade composite make up all contribute to the desired cut. Blade speeds and feed are also a factors. The complexity of the subject cannot be properly detailed in this manual, and it is suggested that you contact your local blade supplier for more detailed information and recommendations for the application.

Below is a chart that can be used as a guide line for blade selection and a percentage chart for determining the speeds and feeds for material after determining the Rockwell hardness.

The chart below shows material shape and sizes of square solid, round solid, and tubing, channel, and angle. The size range from 0” - 12” is diameter; the column under the shapes gives recommendation of a vari-tooth blade. Example: 4” round solid, will require a 3/4 pitch blade.

Note: For structurals and tubing, determine the average width of cut.

Blades must be broke in properly, for longest life and best cut finish. Break in cutting should be done at 1/3-1/2 normal cutting rate, for the 50-100 square inches.

NOTE: Below are the three most commonly used types of blades. The Bi-Metal blade is the most durable, for standard types of cutting applications. The teeth are made of high speed steel and welded to a backing material. The cutting edge contains 8% cobolt with a Rc of 64 to 68. (These blades are more difficult to weld than standard carbon.) The carbon blade is the least expensive with reduced blade life. The back of the blade is made of hardened material with a Rc of 31 to 37 and tooth hardness of 64 to 66. The carbide tipped blade has carbide inserts welded to the blade teeth with a Ra rating of 92

Manual V-16, V-24, VH-24, V-40 & VH-40 15 – Section I