When the planer blades become dull, the finish quality and productivity decrease. Only an experienced craftsman can properly sharpen such knives, since it is necessary to observe the sharpening angle along the entire length. But if you make a device from emery and MDF sheets, then even a beginner will perform a high-quality sharpening.
It will take
- melamine sheets 18 mm thick;
- emery machine;
- bolts, washers, nuts, screws;
- aluminum channel;
- wing nuts;
- steel strip and corner;
- threaded bushings for wood;
- steel handle;
- planer knives, etc.
Instruments: drill, glue gun, tilt disc circular, welding, wet sandpaper, clamps, etc.
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The process of making a device for sharpening knives of a planer machine
Cut out a rectangle from the sheet for mechanical emery and drill a couple of holes in it opposite the fastening perforations of the emery. We drill large blind holes with a diameter, and small holes in the center.
We insert bolts with washers from the side of blind holes, onto which we lower the emery base on the other side and tighten with nuts.
Place the emery with the base on a large rectangular sheet in the center, aligning the trailing edge of the base with the long side of the large sheet.
We put two plates on the glue close to the base. Having verified the right angle between the plates and the base, we fix them with screws.
On the plates we place the same ones with an inward displacement of 1/3 of the width and fasten them to the lower screws. Insert the base under the emery into the resulting grooves and make sure that it moves freely in them.
Cut out 4 triangles from the sheet with angles of 90, 45 and 45 degrees. We glue them perpendicular to the long side of the large sheet with the hypotenuses outward. We fasten with screws from the bottom of a large sheet.
We cut one side of the long board on a circular at 45 degrees.
On the wide side, we make two parallel longitudinal grooves along the cross-section corresponding to the aluminum channels.
We lay a board with an edge at 45 degrees on triangles so that the edge is one piece with the vertical legs, and fasten them with screws to the triangles.
We put the aluminum channels on the glue in the grooves of the board, squeeze them with clamps and leave them until the glue hardens.
We measure the width and height of the aluminum channels to adjust the circular disk and cut out two bars to move along the channels.
We fix the bars with screws longitudinally to the board with an edge of 45 degrees. We rub the bars with wax or paraffin for better sliding in channels.
We put the board in bars in the channels, and combine the cut with the cut of the bottom board.
In the steel strip along the edges we make 2 holes and 5 holes along the length with a slight offset from the center.
We insert 5 bolts into the holes of the strip and weld them. We put on washers on the bolt rods and screw on the wing nuts.
In a board with bars on the long side, we drill sockets with through holes and drive threaded bushings. We bolt to them a steel strip with bolts.
In parallel to the strip, fasten the steel handle with screws. We put the board with the bars back into the channel guides.
We make elements from a steel corner – narrow strips with a hole in the center from a shelf with a small grip on another shelf.
We put these elements on the rods of the bolts with the “noses” down, then the washers and screw the wing nuts.
We fix the knife with stops and wing nuts, ensuring parallelism relative to the edge of the board. The sharpening angle is set automatically by the design of the fixture.
Sharpening is simple: turn on the emery, move the knife left and right and press the emery against the knife as it is sharpened.
To remove burrs and folds, we grind the back of the knife with “wet” sandpaper.
Having installed the sharpened knives on the jointing machine, we are convinced of the quality of their sharpening when processing blanks.