How to properly disassemble the drill chuck

04-05-2018
Power tools

Drill is one of the most used tools at home. But sometimes the question arises how to disassemble the drill chuck. With all the reliability of the tool sometimes fails. One reason may be a failure of the cartridge.

Electric Drill Diagram

Diagram of the device electric drill.

The design of the cartridge is quite simple, and almost all drills have similar elements. At the same time, the compactness of the location of parts and fastening strength can be difficult. The issue of disassembling the tool often becomes quite relevant.

Varieties of ammunition

Springless drill chuck

Springless drill chuck.

The cartridge is an important element in the design of any type of drill - a punch or a screwdriver. It provides a strong fastening of the drill and the transfer of rotational motion from the shaft. Based on the functional features, it is possible to distinguish two main components - the fastening system of the drill and the fastening system of the chuck to the main shaft of the drill.

The mechanism of fastening the drill highlights the chuck cam type used in most drills. Its principle of operation is based on the movement of special metal sponges (cams) placed on the cone. The cylinder, rotating on a conical surface, provides movement of the cams in the transverse direction, bringing together or pushing them apart. Accordingly, the drill bit placed between the cams is clamped or released, depending on the direction of movement of the cams.

Electric drill cartridges vary in the way the cylinder (adjusting sleeve) is set in motion around the cams. Two options are used - key (normal) and fast-clamping. The key method implies the presence of additional gearing between the elements and is implemented using a special key that drives the gear. The quick-tightening version is based on running in a sleeve over a threaded surface made on cams. Rotation of a sleeve is made manually.

Drill Chuck Diagram

Diagram of a classic drill chuck.

By the method of mounting on the tool shaft, the cartridges can be divided into threaded and tapered. Threaded twist on the shaft due to the threaded connection. Cone use the principle of Morse cones, i.e. have a conical end hole, on which the tapered shaft end fits tightly.

The cam-type electric drill chuck reliably fixes drills with a cylindrical shank of different diameters in a certain range. The most common items are manufactured with a range of installed drills 0.8-10 mm and 1.5-13 mm.

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What parts is the cartridge

The whole design of the cam cartridge is assembled on the inner cone sleeve (shaft) - base. There are guide rings for cams on the base surface. The cams themselves are made of metal bars and have on the outer surface threaded cutting in the form of transverse grooves. At the top of the bars cut into a cone. The grooves on all the cams are made in such a way that when combining the bars, the grooves form a single thread.

Cams (in the amount of three or four pieces) are placed on the conical surface of the base and are passed through the guide rings. On top of the base with cams, an adjusting sleeve is installed, made in the form of a cylinder with an internal thread, similar to the thread on the cams. A washer and an annular bearing are fitted on the front side of the chuck. Finally, the whole structure is fixed with a nut with teeth on the outside.

Common types of drill chucks

Common types of drill chucks.

On the back side in the center of the base there is a hole for mounting on the drill shaft. Depending on the type of cartridge, this hole has the shape of a threaded cylinder or a cone shape without a thread. Hole - not through. On the surface, which silences the end hole, another hole of a smaller diameter is made with a left-hand thread for the locking screw.

After assembly, the cartridge is a single unit and operates as follows. A cylindrical sleeve with its thread rolls around the threads of the cams, while it does not have the possibility of longitudinal movement. This movement along the base surface is forced by the cams. Since the base has the shape of a cone, the cams, moving longitudinally, are simultaneously forced to converge in the transverse direction.

In the key type cartridges, an additional retaining ring with threaded knurling on the surface is installed. The gear moves along this thread, the hollow shaft of which is brought into the socket on the sleeve. Drive this gear by turning the key. Gear, running around the ring, rotates the adjusting sleeve.

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Installation and removal of the cartridge

The device fast-chuck

The device keyless chuck.

The cartridge is mounted on the main shaft of the electric drill with a hole at its base. It either twists (threaded mounting type), or tightly settles on the cone (tapered mounting type). Through the hole in the base of the cartridge is fixed locking screw with left-hand thread. To do this, the jaws are fully diluted, and the screw is vertically inserted into its hole and twisted counter-clockwise.

Those who disassemble the cartridge, know that first it must be removed from the shaft of the drill. The removal is as follows. Fully divorced sponges. Phillips screwdriver unscrew the locking screw, which is located inside and below the cartridge between the cams. The screw is unscrewed in a clockwise direction. Then the drill is fixed in a stationary state, and the cartridge is unscrewed clockwise. Usually after using the tool, it is firmly fixed on the shaft. So you have to make an effort.

Diagram of the percussion mechanism of the drill

Diagram of the percussion mechanism of the drill.

The body of the drill should be clamped in a vice, and the chuck is unscrewed with a gas wrench. In order not to damage the liner, a gasket should be used between the key and the liner. If this effort is not enough, then you can use two keys. The electric drill shaft is firmly fixed with one key, and the cartridge rotates with the second key.

The cartridge with a tapered mount is removed much easier. The drill is fixed motionless in a vertical position in a downward direction. At the back of the end surface of the cartridge at first slightly tapped with a hammer over the entire area. Then with stronger blows in several places, the cartridge is knocked off the shaft. To evenly distribute the force, you can install a wrench on the surface and make blows on it.

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Disassembly drill chuck

Diagram of the device chuck

Diagram of the device clamping cartridge.

The question of how to quickly disassemble the drill chuck is solved in the following order. The element is secured in a vice, preferably through a pad of soft metal. First, unscrew the top nut with teeth. You can use a gas wrench, but this must be done carefully so as not to damage the nut. Pre-should be oiled. The bearing and washer are then removed.

The cartridge is removed from the vice, and the sleeve is manually unscrewed from the base. If the sleeve is jammed, then the cartridge can be disassembled only by applying force. For this, he is clamped again in a vice, but with the back side up. Oil is poured between the base and the sleeve. Using the gas key unscrew the base.

If there is a lower lock nut or ring, then they must first be removed.

The base is removed from the sleeve. Cams are removed from the guide rings and removed from the conical part of the base. The issue of tool disassembly is resolved.

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Removing the shaft with chuck

Sometimes there is a situation when the removal of the cartridge from the shaft of the drill is very difficult. In this case, you can remove the cartridge with the shaft. To do this, first opens the tool body. Unclip the mounting clamp, release the retaining ring. Then the gear and key are removed, by means of which the gear is attached to the shaft. The locking ring, the bearing and the spring are removed successively from the shaft. The cartridge together with the shaft is removed from the tool body.

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Chuck faults

After the cartridge is disassembled, you should carefully examine all the details. Repairs are easy to make if the parts are undamaged and jamming is caused by metal chips entering adjacent parts. In this case, rinse all the parts well with oil or kerosene. To do this, you can use a soft brush. After cleaning the parts, the assembly can be performed in the reverse order, but manually, with little effort.

Most often, a malfunction is caused by wear or damage to the threaded and toothed surfaces. If this damage is small and local, then you can try to fix them by polishing with a file or sanding cloth. In the case when grinding does not help, the cartridge should be replaced completely.

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Necessary tool

If it is necessary to remove and disassemble the chuck of an electric drill, then the following tool should be prepared:

  • vice;
  • pliers;
  • screwdriver;
  • hammer;
  • mallet;
  • chisel;
  • file;
  • sanding pelt;
  • tassel;
  • oiler;
  • gas key;
  • Adjustable wrench;
  • set of wrenches;
  • awl;
  • file;
  • calipers.

The issue of disassembling the cartridge is solved in different ways. Sometimes it is very easy to do, and sometimes there are complications. In any case, the cartridge can be disassembled, and this is done by hand.