DoAll TF-2025M, Instruction Manual

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16
Reducng Cuttng Rate & Band Speed for Ppe, Tubng
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 sectons of the same sze.
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 mm & over)
*Based on 5 inch (127.0 mm) solids.
Cutting Rate to Thickness Relationship.
SAW HEAD APPROACH RATE
1. After the stock has been positioned for cutting and
the Saw Head Control selector is placed at the
"FWD/AUTO" setting, the saw head's approach
(traversing) rate is regulated by the Head Approach
valve.
2. Correct head approach is important for helping: (a)
Determine overall cutting accuracy and finish of
cut; (b) Improve blade life by eliminating breakage
and tooth strippage at the cut's start and break-out
points.
3. To move the saw head if the band drive motor
is not running: (a) Place the saw in "MANUAL"
operating mode; (b) Move the Saw Head Control
selector to "FWD/AUTO"; (c) Make the desired
Head Approach valve setting; (d) There must be
some Feed Force setting.
4. Push the Band/Cycle Start button and run at a
very low speed to check for proper band tracking
against the each bandwheel rear flange.
POST ADJUSTMENT
1. Post and upper saw guide height is regulated by
the Post selector switch on the control panel.
2. Sawing results will generally be more satisfactory if
the post and upper saw guide are kept as close as
possible to the material being cut. Doing so helps
reduce saw band vibration and contributes to more
accurate sawing.
When the saw head has been tlted, make
sure the post and saw gude wll clear the
materal.
FEED FORCE ADJUSTMENTS
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 clockwse to "decrease"
pressure, counterclockwse 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 operation
to obtain the best cutting rate consistent with desired
blade life and stock cut finish. Always be sure to
take a good chp.
• 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 damage.
• Generally, top performance from a sharp saw band
results from relatvely low Feed Force valve
settings. 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
changing stock cross-sections. A balancing valve
enables the saw band to maintain a uniform cutting
rate.
SAW BAND PREPARATION (Continued....)