|1. Stock preparation. |
A. Resaw, join, thickness, and square the center block and cheeks. Use the plane iron as a gauge to assure 1/16" adjustment clearance on center block.
B. Plane the glue joint surfaces of center block & cheeks to remove joiner marks.
2. The ramps.
A. Layout cuts in the body for 45° plane iron ramp & 65° forward slope. The mouth is generally about 1", increasing to 2", forward of center, varying according to the length of the plane. The forward ramp may be curved to allow finger room to clear shavings.
B. Bandsaw ramps and surface. Plane iron ramp flat & square to center block sides. Save the cutout.
C. Route cap screw slot 3/ 4" wide, centered on rear ramp from the top of the plane to within 3/ 4" of the bottom
3. Putting it back together.
A. Lay one cheek on the bench and clamp the rear center block to it, flush to the bottom and end. Draw a line along the ramp onto the cheek.
B. Hold or clamp the sole stock to the forward center block with an edge of the sole flush with the forward ramp.
C. Place the iron on the rear ramp, bevel down.
D. Lay the front block and sole assembly on the cheek. Slide it toward the iron, making contact at a point where the iron is about 1/16" from protruding beyond the sole. Mark the front ramp's position on the cheek.
E. Index center blocks to cheeks with dowels.
4. The plane iron assembly.
A.Shape the breaker, starting with a bend of no more than 1/ 8" centered about 3/ 8" from an end. Grind a fair slope from the edge to the center of the bend. Continue shaping with a file and finally a stone, keeping in mind that the curve must not impede the flow of shavings. The edge needs to come in full contact with the iron so that shavings cannot jam between them.
B. Locate for the center of the cap screw, marking at the lower end of the slot in the iron. Drill and tap for the cap screw, ideally perpendicular to the cap iron surface.
C. Hone the iron.
5. The cross pin.
A. Pencil a short line parallel to the bottom 11/ 4" from the bottom of a cheek in the area of the cross pin location. Locate the rear center block on index pins and place plane and cap iron assembly on the ramp. Draw a line parallel to the assembly 7/ 16" away from it. The intersection of these two lines is the cross pin center. Transfer the center points to the outside of the cheeks and drill 5/ 16" holes through the body of the plane.
B. Make cross pins and allow for extras. Layout and cut several tenon shoulders on the pin stock before cutting to final length. Use the center block as a gauge to assure that the distance between the shoulders is less than the width of the center block. Round the tenons with a knife or file, checking the fit in a test hole.
A. Dry clamp the plane body. Make sure that the index dowels and cross pin do not protrude beyond the cheeks. Use clamping cauls to protect the body and distribute pressure. If needed, clamp a strip of wood to the bottom of the center blocks so that they are aligned. Have enough clamps on hand to clamp at 2" intervals with none across the opening. Check that the cross pin is free to turn, that it is parallel to the ramp, and that you can get your fingers between it and the forward block to remove shavings. Place the iron assembly in the plane to be sure that there is at least 1/ 8" clearance for a wedge.
B.Glue-up body & cheeks. REMEMBER THE CROSS PIN! Place it in one of the cheeks before applying any glue.
7. The sole.
A. Scrape any excess glue from the plane bottom. Use a wooden shim in place of the iron assembly, snug up the wedge and make a light pass over the joiner. Heavy jointing will quickly increase the mouth opening.
B. Orient sole stock so that the "fur" of the working surface is running toward the back of the plane.
C.Mark the location of mouth opening on the sole and route or cut the slot.
D. Check the relationship of the sole to the iron as was done when determining the distance between the center blocks. The plane iron can now be a little closer to the surface of the sole, within about 1/ 32".
E. While holding the sole in place (the iron can come out), look inside the mouth opening from above and note whether or not you can see the sole. Ideally, it would still line up with the forward ramp. If you can't see it, some of the forward ramp needs to be filed to provide clearance. If you can see the sole, make a mental note of how much of it you can see.
F. Align the forward edge of the slot along the forward ramp with the relationship noted.
G. Index the sole stock to the plane body with small dowels or brads.
H. Draw a line along the rear ramp onto the sole. Remove the sole from the index pins. Using the cutout as a guide, chop a 45° ramp at the back of the opening. File the feathered edge blunt so that it does not tend to break off.
I. Glue the sole to the body, using clamping cauls against the sole and on the top of the body.
H. After glue-up, ensure that the ramp on the sole is flush with the plane iron ramp. Otherwise, a false reading will be obtained when filing the mouth opening and a bump will be raised on the sole when the iron is wedged into place.
8. The plane iron wedge.
A low angle is best to securely hold the iron, yet it must be steep enough to come to a firm stop. Use the cutout for wedge stock.
A. True the plane sole. The wedge should be as tight as it would be in use to truly flatten. Truing is done with a long strip of sandpaper clamped to a table saw top. With little more pressure on the paper than the weight of the plane, make a light pass. High spots, usually behind the iron, will reveal themselves as abraded areas. Continue sanding with a light touch, noting progress often, until the entire surface has been abraded.
B. File the final mouth opening. As you work, angle the file so that the opening is forward of perpendicular on the inside, allowing for shaving clearance.
Place iron assembly and wedge under the cross pin. Set the wedge with firm rap of a small (4-6 oz.) hammer. The cutting depth of the iron is most effectively controlled by tapping it downward. Sight the cutting depth from the back of the plane. Catch a reflection of light on the bevel of the iron. Tilt the plane up until you are looking directly along the sole's surface. Tap the iron to bring it just above the that apparent line.
The iron is backed out by rapping on the back end of the plane. Hold the plane with the palm on the iron to keep it in the plane should the wedge loosen.
Crankiness in a plane is most commonly due to a bump behind the iron. It may reveal itself in use in at least two ways. If the iron grabs at the beginning of a cut and then skips as the plane moves entirely onto the surface, check the area behind the iron with a straight edge across the planes width and along its length. Suspect a bump when it seems that either one corner of the iron or the other persists to dig in.
With the frog out of the throat, your instrument can be singing.
Soften the edges of the plane and use it before gradually shaping to your satisfaction.
© 1996 David Welter