CHECK THE SETUP
After changing or sharpening the knives in your planer, make a test cut.
Using calipers, check the thickness of the board across the width. If
the thickness isn’t precisely the same at both edges, the knives are not
parallel to the table. If the planer cuts a deep snipe at the beginning
or end of a board, either the bed rollers aren’t properly set or the
feed roller pressure is not adjusted correctly.
CHECK THE STOCK
If necessary, clean the wood; avoid plywood and used wood. Set the feed
rate and the depth of cut according to the wood species. The harder the
wood, the slower the feed rate and the shallower the cut should be. The
width of the stock should also affect your settings — use a slower feed
and shallower cut for wide stock.
Inspect the lumber to
find the grain direction and slope. As in jointing, the
grain slope
is important in planing. Once again you want the cutterhead to cut
with the wood grain, shaving the slope
downhill.
You can usually find the slope simply by looking at the edge of the
board. When working with
rough-sawn
or
S2S
lumber, give the edge a few licks with a hand plane to reveal the wood
grain.
If it's hard to read
the grain on the edge and you're surfacing plain-sawn stock,
consult the "arrows" on the face of the board. Arrows form when the
sawyer slices through the annual rings at an angle to the grain. If
you're looking at the exterior or "bark" side of the
board, these arrows point uphill. On the interior or "heart"
side, they point downhill. Knowing this – and which way your
cutterhead spins – you can determine how to feed the board into the
planer. So I don't have to think this through every time I plane, I use
this mnemonic: Bark side up, arrows advance; bark side down,
arrows retreat. |
PLANING WITH
THE GRAIN
1
To avoid tearing and chipping, the knives must cut "downhill" on the
grain slope.
2
To determine how to feed plain-sawn
stock through a planer, note which way the
“arrows” point. Then inspect the end grain to find the "bark side" of
the board — the side nearest the bark when the tree was standing.*
3 If
the bark side is up, feed the wood in the same direction that the arrows
point. If it’s down, feed it in the opposite direction.*
PLANING THIN
BOARDS
When planing
a very thin board — thinner than the planer would ordinarily cut — rest
it on top of a thicker board and send the two boards through the planer
together.* |
Figured wood doesn’t
have a consistent grain direction, making it difficult to joint or
plane. No matter which way you feed the wood, you’re planing with the
grain part of the time and against it the other part. When you’re
planing against the grain, the knives tend to lift the wood fibers and
tear them out, leaving the surface chipped and gouged.
A router, however, cuts
the wood from a different angle and is not as likely to tear figured
grain. With the aid of this jig, you can surface small and medium-sized
boards. Secure the work in the trough with wedges, and fasten the router
to the extended base. Mount a 1-inch straight bit in the router, rest
the base on the sides of the trough, and adjust the height of the bit to
cut the stock to the proper thickness. Turn on the router and slide it
back and forth across the jig, shaving the surface of the wood. |
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