For many operations performed in the training workshops and technical circles, very comfortable would be portable universal tool like dental drill. However, to acquire such is almost impossible, and, as always in such cases, the question arises: is it possible to make something similar on their own?
The main scarce item of the device is a flexible shaft. But almost the same principle operates the flexible shaft of the speedometer of a car or motorcycle, and the decommissioned item to get is easier.
I used the cable from a truck, it was more appropriate to attach both to the motor and to the working head.
Structurally, the mini-drill was formed from three parts: motor, flexible shaft and a working head with a standard three-jaw Chuck of the drill, with a short Morse taper. The drive used motor type BCS-1 power of 35 W at a voltage of 220 V. you Can use any other engine with power up to 60 watts and rpm 2700 — 5000 rpm.
Structures, the working head is simple and can be seen from the figure. Going ome in that order. On the shaft to limit napresovuyut ball bearing No. 18, then along the shaft of his stick in the groove of the body, put the spacer and pressed all the way into her second bearing. Before Assembly, both bearings are thoroughly washed in kerosene, and after overmolding or grease lubrication grease or technical vaseline. The shaft should easily without jamming rotate in the housing. After this, screwed front and back covers of the housing. Then the shaft is inserted into the end of the cord and screwed swivel nut of the flexible shaft.
Scheme of mini-drills and tools to it:
1 — cartridge (No. 1A), 2 —front cover, 3 —ring (D16T), 4 — housing of the working head (D16T), 5 — pipe, 6 — shaft (St. 45), 7 — bearing, 8 — back cover (D16T), 9 — ring (D16T), 10 — flexible shaft, 11 —transitional bushing (D16T), 12 — area (D16T), 13 — base (PCB B 10 mm) 14 — motor 15 — back area. And — cutter Assembly and scheme holders, B and polishing the head n of its holder.
The engine is mounted on the base in the following order. On the right size Board or thick plate of the PCB is fastened with two screws М4Х10 area, and between them — an electric motor. To the right corner with the screws М5Х12 attached adapter sleeve and the engine; to the left are inserted the ends of the studs that connects the front and back cover of the motor. Then connected the other end of the cable of the flexible shaft and its nut screwed on the bushing. On the basis of the engine can be positioned condenser in the casing and the switch. As for the legs, the base you can use a rubber cork from the health bubbles.
To operate a mini-drill can be made and microtools. It could be ready dental burs, grinding discs, drill bits with a diameter up to 6 mm. For homemade enough to make a tool holder-base and the working part can be changeable: mills, emery stones, saws. They put together with washers on the holder and are fixed with nuts. To operate disc cutters and saws, the working head must be secured stationary, for example by means of inserts and the table vise. It is better to make a special table With the appropriate mount for the working head.
Using a mini-drill handy to drill holes in plastics and metals, to sharpen cutting tools, polishing parts, mill a complex surface, to engrave, to cut the sheet material, to perform many operations.
Alexander ASHAEV, G. Roshal
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For many operations performed in the training workshops and technical circles, very comfortable would be portable universal tool like dental drill. However, to acquire such is almost impossible, and, as always in such cases, the question arises: is it possible to make something similar on their own?