Oliver 4420 Owner's Manual page 53

Problem
Workpiece came out
twisted.
Excessive snipe
End of workpiece
chipping
Chipping in workpiece
surface.
Indentation in
workpiece surface.
Fuzzy looking finish.
Glossy looking finish.
Long line or ridges
running along the
length of board.
Serrated marks on
workpiece.
4420 Planer
Possible Cause
Workpiece is twisted
before the cut.
Feed/bed roller is not
parallel with the
cutterhead.
Extension tables slope
down.
Long workpiece is not
supported properly.
A small amount of
sniping can happen
sometimes.
Aggressive depth of cut
for the wood type.
Planing end grain.
Damaged cutter.
Planing against/across
grain; or knots.
Too much material
removed in one pass.
Dirty rollers.
Inefficient chip
removal.
Wood moisture content
too high.
Dull cutter.
Some wood types tend
to have fuzzy grain.
Dull cutter.
Cutting depth too
shallow.
Chipped cutter.
Cutting depth too
shallow.
OLIVERMACHINERY.NET
Possible Solution
Planer is not the tool to flatten a twisted
workpiece. Flatten one side with a jointer before
proceeding with a planer.
Adjust roller/table parallelism.
Adjust the extension tables to make them
parallel with the planer bed.
Use auxiliary rollers to support long workpiece.
Add an extra 6" length on a workpiece for
planing, and then trim off the ends.
Reduce depth of cut.
Do not plane end grain. Use a drum sander
instead.
Rotate/replace cutter insert.
Avoid planing workpiece with knots. Plane along
the grain and perform downhill cut whenever
possible. Moisten problematic areas before
planing.
Reduce feed rate / depth of cut.
Remove all buildups on infeed, outfeed, and
table rollers.
Check dust collection system for suction.
Adjust chip breaker and chip deflector.
Only process wood with less than 20% moisture
content.
Rotate/replace cutter insert.
Adjust feed rate / depth of cut.
Use sharp cutters.
Rotate/replace cutter insert.
Increase depth of cut.
Rotate/replace cutter insert.
Increase depth of cut.
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