Darex V-390 - Manual (Page 14)

14
Troubleshooting
Q: I aligned the drill bit and sharpened it, but no material gets re-
moved, why ?
A: You may have allowed the paddle to knock the drill bit back into
the chuck. Carefully realign the drill bit in the alignment port
again. Making sure the drill bit is pushed all the way against the
drill stop.
A: You may not have tightened the chuck tight enough to hold the
drill bit in place. When the drill bit hit the wheel it was pushed back
into the chuck. Realign the drill bit again using more force to
tighten the jaws on to the drill bit.
A: When changing point angles it may be required to advance the
Material Removal Knob to a higher number. Realign drill bit at new
Material Removal Setting.
Q: I'm getting negative relief! Negative relief is present when the
heel behind the cutting lip is higher than the cutting lip on the drill
bit. When negative relief occurs the drill bit will not cut.
A: To correct this problem, move the paddle toward the right, try
number 2 or 3 for an increased relief setting. Realign the drill bit
and re-sharpen.
A: Maintain consistent inward pressure on the chuck during the
sharpening process. Make sure grinding is completed and the drill
bit has been sparked out. (Grinding noise reduced to a minimum)
A: The Material Removal Knob may be set to remove too much
material. Reduce amount of material being removed from the end
of the drill bit by setting the Material Removal Knob to a lesser
number. Realign drill bit and sharpen.
Q: Why is the drill point off center? If the tip of the drill bit ap-
pears to be sharpened off center, check the following items:
A: Make sure that there are no particles between the chuck jaws
and the drill bit, which could hold it off center.
A: Make sure the closing knob is tightened firmly enough to hold
the drill bit on center.
A: During the sharpening process be sure not to push unevenly
while rotating the chuck.
A: The drill may be bent. Roll it on a flat surface to check for
straightness.
A: Spark out the drill bit.
Q: Why don’t my drills align correctly, like the "correct" diagram?
A: There may be a burr on the drill shank (remove burrs with a
flat file).
A: The drill may be too loose or too tight in chuck.
Q: What can I do about the flat spot between the lip and the
heel?
A: The flat spots or chattering on a sharpened drill, is the result of
an incomplete or irregular rotation of the chuck in the sharpening
port. To correct, apply firm, not excessive inward pressure and
rotate the chuck smoothly while sharpening. Do not lift up on the
chuck while rotating it. Be sure to complete the grind.
☞
TIP:
If the chisel angle on the tip
is too far clockwise, realign
the drill with a reduced
relief setting.
☞
TIP:
Clean CBN and diamond
wheels with an oil-less
solvent, for example,
automotive brake cleaner.
☞
TIP:
Sparking out drill bits while
sharpening improves drill
point concentricity.
☞
TIP:
Darex manufactures other
sharpeners capable of
creating a variety of
specialty points.