DoAll DC-330NC - Saw Guide Arm Adjustment; Feed Force Adjustment

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3. Important factors which inuence band tension
settings are the size of stock to be cut and desired
band life. General rules-of-thumb are: (a) Lower
tensions will increase saw band life; (b) Greater
tension is required as spacing is increased between
the saw guide arms; (c) Higher band speeds require
greater tension.
DO NOT start the band drive motor unless the
saw band has been properly tensioned.
SAW GUIDE ARM ADJUSTMENT
1. The machine's right saw guide arm is xed. The
left saw guide arm can be adjusted as follows to
accommodate varying stock widths: (a) Loosen
the left saw guide insert adjustment screw by turn-
ing counterclockwise; (b) Loosen the left arm's
locking knob by turning it counterclockwise; (c)
Move the arm along the slide bar until it is as close
as possible to the stock; (c) Turn the locking knob
clockwise to tighten (hand tighten is sufcient); (e)
Tighten the insert adjustment screw as previously
instructed.
DO NOT move the left saw guide arm while
the saw band is running.
2. The best cutting results are generally obtained
when the saw guide arms are positioned as close
as possible to the stock.
FEED FORCE ADJUSTMENT
1. Feed force is the pressure exerted by the workpiece
against the saw band's cutting edge. It is controlled
hydraulically and regulated with the Feed Force
valve. Turn the valve clockwise to "decrease"
pressure, counterclockwise to "increase" it.
2. The following are important factors to consider when
setting or adjusting the Feed Force valve:
• Turn the Feed Force valve to a low setting if the
correct feed force is not known. The operator can
then increase or decrease pressure during opera-
tion to obtain the best cutting rate consistent with
desired blade life and stock cut nish. Always be
sure to take a good chip.
• Never start a cut with the maximum Feed Force
valve setting. Blade damage may occur.
• Certain work-hardening materials will require a
moderately heavy initial Feed Force valve setting
to assure immediate penetration of blade teeth.
Light feeds on these materials may cause the blade
to slide over the stock resulting in saw band dam-
age.
• Generally, top performance from a sharp saw band
results from relatively low Feed Force valve set-
tings. It will be necessary to increase the setting as
the saw band becomes duller. This will help keep
the cutting rate constant throughout the life of the
saw band.
• Feed force adjustments are not necessary for chang-
ing stock cross-sections. A balancing valve enables
the saw band to maintain a uniform cutting rate.
Reducing Cutting Rate & Band Speed for Pipe, Tubing
and Structurals
1. Increasing loading per tooth occurs when sawing
thin stock sections. Although the blade teeth can
bear some overloading, a cutting rate reduction
must be made.
2. Proceed as follows when it becomes necessary to
modify solid section sawing recommendations: (a)
Measure the thinnest stock section to be cut; (b)
Apply the corresponding percentage factor from the
chart below; (c) Use a high band speed, but never
exceedthemaximumspeedrecommendedfor
stock sections of the same size.
SECTION FACTOR TO APPLY
THICKNESS TO MINIMUM CUTTING
RATES GIVEN BY JOB
SELECTOR*
Up to 3/16 inch 40%
(0 to 4.8 mm)
3/16 to 3/8 inch 50%
(4.8 to 9.5 mm)
3/8 to 5/8 inch 60%
(9.5 to 15.9 mm)
5/8 to 1 inch & over 70%
(15.9 to 25.4 mm & over)
*Based on 5 inch (127.0 mm) solids.
Cutting Rate to Thickness Relationship.
SAW BAND PREPARATION (Continued....)