|Filing - Course: Technique for Manual Working of Materials. Trainees' Handbook of Lessons|
One hand grips the file handle while the palm of the other hand (guiding hand) lies on the end of the file blade and holds and guides the file in the horizontal plane.
One hand grips the file handle while thumb and fingers of the other hand (guiding hand) grip the end of the file blade guiding the file.
One hand grips the file handle while the fingers of the other hand press onto the file blade so as to avoid deflection of the file blade
(Filing without guiding hand is also possible)
6.1. Filing of straight faces
There are three types of filing strokes
Suitable for removing big quantities of chips with rough surface
The traces left by changing the working direction are noticeable on the surface as peaks and valleys!
Working traces in parallel with the longest edge of the work - light guidance of the file for smooth finish.
Testing of faces for flatness and angularity is preferably done by bevelled steel straightedge and bevelled edge square!
6.2. Filing of curved faces
Small outer radii are filed longitudinally in the direction of the radius.
The working movement is featured by a rocking feed movement opposite to the radius
Filing on big outer radii is at right angles to the radius starting at one side and working to the other side with slightly oblique stroke.
Filing on inside radii of any size is at right angles to the radius. The radius of the file (round file, half round file) must be smaller than the radius of the work.
Testing of the radii for accuracy to shape is by radius gauges for outer and inner radii.
6.3. Filing of recesses and openings
The file is carefully selected depending on the size and shape of the recesses or openings It must be smaller than the recess or opening to be filed.
Testing for accuracy to size is by measuring instruments, for accuracy to shape by adequate counterparts.
6.4. Filing of chamfers
On big workpieces filing of chamfers at an angle of 45 degrees is performed with vertically inclined file. Small workpieces may be clamped in an angle vice and are filed horizontally.
On round stock (bolts) filing of chamfers is performed with the file laterally inclined by 45 degrees, filing step by step around the round stock with the file whipped outwards
Testing of the chamfer is by Judgement by the eye, particularly with respect to evenness and surface finish.
Which kinds of stroke are to be subsequently used when filing
Why can evenness with good surface finish be achieved only by
What is typical of the working movement when filing small
Which requirements are to be met when filing inside
What makes the difference between filing of big and small