Knifes for planes. Knifes for planes produce in the length 180мм, two-layer, thickness 1,9-3мм. The first, or supporting, a layer produce from a soft steel of the mark 30, the second, or plating (cutting), length 55мм, thickness 1±0,5мм - from a steel of marks 9ХВ, 9Х5ВФ, 9ХС. Earlier knifes named pieces of iron, and two-layer-navarnymi.
Two-layer knifes to sharpen much easier. The industry produces also knifes completely from a plating steel. The width of knifes depends on the tool name.
Knifes produce unary and double. Double consists of the knife and imposed on it struzhkolomatelja or gorbatika. Such knife planes more purely and regulates a thickness of a removed shaving. Struzhkolom should adjoin densely to a knife, with a backlash no more 0,05мм. Struzhkolom establish from a cutting edge of a knife (or stings) on distance 0,5-2мм that depends on a thickness of a shaving and desirable cleanliness of planing. Such knife has a round aperture with a longitudinal cut in total length 90мм. On a cut move struzhkolom and fix the screw from the bottom party of a knife. Struzhkolomy happen flat and to camber - a hump, from here and the name gorbatik. Knifes for planes are resulted in drawing 15. Working capacity of knifes depends on quality of a steel. The facet acts in film at knifes at an angle 45° therefore the cutting edge or a sting is formed. Knifes of planes should be correctly inserted in kolodku. There are various receptions of an insert of knifes in kolodku.
15. Knifes for planes :
And - for sherhebelja: 1 - a varnishing layer (cutting); - a double knife for a plane: 1 - a knife; 2 - strzhkolomatel (gorbatik); 3 - the screw; in - work of a plane with an unary knife; e - work of a plane with a double knife: 1 - a shaving; 2 - gorbatik
Correctly established knife fix. If the sting because of a sole acts more put a hammer strike poprobke and if does not act by a tail part of a knife. Knife strengthening weakens, it establish, as it is required, and fix. Slantwise established knife correct, putting blows by a tail part from that party of a knife from which pressed more it is visible (fig. 16).
16. Plane adjustment :
And knife check; - derzhanie a plane for klinok and a knife; in - a hammer grasp
We Will consider work of planes with an unary and double knife.
the Plane with an unary knife at pressing it runs into wood, lifts the cut off shaving which on a knife and klinku is deduced from letka outside. Lifting a shaving, a knife slightly nadkalyvaet ahead of itself wood on small size. Therefore the tree surface turns out not so pure, that is with appreciable inclinations. The plane with a double knife eliminates this lack.
the Plane with a double knife works so. The cut off shaving gets at once on struzhkolom, or gorbatik, is bent upwards almost at right angle and breaks. The wood surface turns out purer, without otshcheplenija or nadkalyvanija.
Service life, or a sharpness of a sting of a knife between sharpenings, define the planing area (expressed in square metres) the sample of fur-tree wood of 3rd grade (wood with knots), humidity no more than 22%: for sherhebelja - 1м 2 , unary and double planes - 1,5, tsinubelej - 0,3, zenzubelej - 0,6, faltsgebelej - 0,4м 2 . Guarantee firmness of knifes for planes, should be not less 120мин planing.