There are many troubles in electrolytic polishing of gears and gear spindles for precision machine elements. Namely these are the irregular deformation of the contour curve of gear flanks and the oval, eccentric deformation of the spindle sections.
In order to determine the actual quantities of these deformation, we measured the dimensional change of gears and the spindles.
As the results we found how to get rid of the undesirable effects of treatment and on the contrary how to make use of the treatment effects for tip relieving and crowning of gear flanks.

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In this report, the effects of workpiece temperature on the cutting force, shear angle, toolchip friction, shearing stress on the shear plane, shape of chips, surface roughness, etc. were investigated. The experiments were performed by orthogonal cutting of steels heated by a small electric furnace on the lathe. The main results were as follows :
1. The decrease of the cutting force by heating the workpiece is due not merely to the decrease of yield shearing stress but also to the increase of the shear angle.
2. In cutting the non-heat-resisting metals as carbon steels a t a very low speed, cutting forces begin to increase by heating over 500°C.
3. Continuity of the chips is closely related with brittleness of the work materials at the cutting temperature.
4. Even by using the tool with-10° rake angle at the very low cutting speed of 1.77m/min, a very smooth surface (about 1μ roughness) was obtained at the higher temperatures than about 600°C. This is due to disappearance of built-up edge at that high temperatures.
5. The heating temperature needed to get rid of built-up edge can be lowered by increasing utting speeds. This is due to the temperature rise by the cutting heat.
6. The size effect on cutting forces decreases by increasing the workpiece temperature.

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Strictly speaking, the torque of hairsprings is not linearly proportional to the angle of rotation of the balance wheel.
This arises from the fact that turning over.the hairspring, the small reaction force results at the outer fixed point besides the moment. In consequence of this non-linearity, the period of vibrations depends upon the amplitude of the balance wheel.
The author could measure this effect by using the optical experimental method which makes possible the extremely large magnification of time.
In this report, the results of preliminary experiments and a part of main experiments are described.
These are as follows :
i) The frictional resistance of the balance-staff dose not affect the measurement of the non-linearity of hairsprings.
ii) A little difference of the form of the outer terminal curve, which is deformed from Archimedes spiral in order to fix by the stud and curb-pins, does hardly affect the non-linearity.
iii) The effect of the strain, which is given to the hairspring in the radial direction at the curb-pins, is proportional to its amount.
iv) The effect of the direction of hairspring eccentricity, which is measured from the center of rotation to the geometrical center of spiral, is remarkable.
This effect was measured in 4 cases of the spiral angle, that is, 8 coils plus 270, 180, 90, 0 degrees from the pinning point to the curb-pins.

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The efficiency of repeated impulse piercing machine is greatly affected by the character of working fluid. For example the piercing speed with telepin oil is approximately 2 times as high as that of the case with light oil, and with water it becomes almost one tenth smaller than in the former case. In this paper the author explained the above-stated facts in relation to the circulation of working fluid and proved that the fluid of smaller viscosity and smaller surface tension is more suitable as working fluid.

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