Friday, May 14, 2010

Learning to Plane - Part V

Chris Schwarz argues that you need a dedicated area for plane sharpening.  After using your planes, dust them off and oil them with either Camilla or Jojoba oil.  The oils won't affect your finish.  In fact, Chris even applies the oil directly to difficult wood or knots to ease planing.  To wax the soles of his planes, Chris uses parafin.  It's essentially mineral spirits.  He waxes after every piece of wood.

Assessing the Wood

Before you plane, look at the end grain.  The bark side of the board is the side where the rings are convex, that is, toward the outside of the tree.  The heart side is where they are concave, or smaller in diameter.  Wood usually cups on the bark side and bows on the heart side.  You tend to get a smooth surface when you plane with the grain.  You can determine that by looking at the edge of the board.  If the grain is rising in one direction, that is the direction you want to plane.  It's like rubbing the fur on the back of a cat; you want to cut with the grain and not against it, which will lead to tearout.  You can also judge from the end grain.  On the heart side of the board, plane from the bottom of the cathedral pattern toward its top.  On the bark side, plane from the point of the cathedral to its bottom.  You would use the same methods to determine the direction for jointing and planing with power tools.  For quartersawn wood, you have to look at the edges; you can't tell from the end grain what direction you should plane.

Assuming the board is cupped, put the bark side down and plane the heart side first.  Once the heart side is flat, flip the board and you can plane without using shims.  When using an end vise, don't put a lot of pressure on the board; the vise can bend it.

Traversing with a Fore Plane

Open the mouth of the plane and use a wide radius (say 8 inches) on the blade.  Plane across the grain.  You can remove lots of wood quickly in this way.  Before traversing (which is what planing across the grain is called), knock off the rear edge of the board, usually with a block plane, to avoid spelching (tearout).

Set the plane on its edge across the board to confirm the existence of a hill.  To remove a hill in the center of the board, plane with the grain to create a slight valley, then traverse the board.  When Chris traverses, he pushes the plane across the board and then pulls it back in a very rapid motion.

Winding Sticks

I took my winding sticks from Philly Planes to the workshop and Chris used those to demonstrate their use.  However, he uses extruded aluminum strips from Home Depot and spray paints one of them black.  Twenty-four to thirty-six inches is a good length.  You can sight at several places on a long board, but you generally don't need to do so.  If you have wind (i.e., the board is twisted), it usually means that two opposite corners are high and you need to plane them.

There's more to tell.  I'll cover it next time.


No comments:

Post a Comment