How To Repair The Stator Of A Makita Hammer Drill With Your Own Hands, Video

2023 Author: Philip Bishop | [email protected]. Last modified: 2023-08-25 07:54

• Beginning of work
• Algorithm for disassembling and manufacturing the stator of the Makita perforator 2450, 2470

• 

• Everything in order
• Stage I
• Stage II
• Stage III
• Making fixture strips
• Winding process
• Stage IV
• Stage V
• Stator impregnation and rewinding:

If you have determined that the stator in your hammer drill is out of order, and you don’t have money for a new one, or you want to repair the part yourself, then this instruction is for you. Dismantling the Makita puncher is so simple that repairing a Makita 2450, 2470 does not cause any particular difficulties. The main thing is to follow the advice given in this article.

Every user who has the skills of a locksmith and knows how to handle diagnostic devices can independently perform a hammer drill repair.

Beginning of work

Any repair begins with an external inspection of the faulty part. And how to find a malfunction of the stator of the Makita 2450 rotary hammer? A malfunction of the stator is most often indicated by the presence of traces of burnt insulation and the appearance of a burning smell. This is the first sign of a short circuit in the stator windings.

But the break can be determined only by ringing the winding circuits.

Algorithm for disassembling and manufacturing the stator of the Makita perforator 2450, 2470

Here is the sequence in the manufacture of the stator of the Makita 2450 perforator:

1. Removal from the stator housing assembly.
2. Removing the old winding, determining the direction of winding, wire diameter.
3. Winding of new coils according to the collected data on templates.
4. Preparation of insulation for new coils.
5. Insulation of new coils.
6. Installing finished coils in the grooves of the core or winding the coils in the core itself.
7. Soldering the leads to the ends of the coils.
8. Reservation of windings of new coils.
9. Impregnation of wound bobbins.
10. Assembling the stator.

Everything in order

Stage I

Use a wooden hammer or block to disassemble the stator. By tapping on the end face of the stator housing, remove the stator from the housing. By the way, to get the stator, you need to disconnect the stator housing from the mechanical housing.

Remember to disconnect the stator lead wires from the terminals that come out in the collector area. One end is attached to the brush holder, and the other end to the 220V power supply wire.

It's time to split it into two halves.

Stage II

Collapsible stator option

Both halves of the stator are glued together with a thin layer of glue. To separate one from the other, you need to hit the stator core with a mallet. If you got a non-collapsible stator, then the wire is dismantled by cutting all the turns from one end with wire cutters. Cutting, disassembling, take out the wire and measure the diameter of the wire and the number of turns. Use only a micrometer to measure the wire diameter. First, the wire must be burned in the flame of a match, wiped off the carbon deposits and, having cooled, measured.

Most often, the coils are impregnated with insulating varnish to prevent separation of the wires.

Use an industrial hair dryer to warm up the coils until they split into separate wires. You can also warm up the impregnated wires on a gas oven above the burner.

When disassembling the stator, measurements must be taken. We need to measure the diameter of the wire, the number of turns in one coil, the percentage of filling the stator slot, the material from which the wires are made. It is recommended to wind only with copper wires.

Wires are classified by cross section. Having measured the diameter of the wire, recalculate its cross-section using the formula S = ηr², where r = ½d.

And now in plain language: the cross section is 3.14 times the half of the diameter squared.

What is this whole vegetable garden for. If it turns out that you have a wire of a different diameter, then you cannot do without calculations. If there is a thin wire, then the winding can be carried out in 2 … 3 wires, the main thing is that their total cross section is not less than that of the initial one.

If there is a wire of a slightly larger diameter, then you can wind it with it, provided that the filling of the slots with the old drive was incomplete.

Stage III

Non-separable stator winding option

To wind the stator coils, it is necessary to prepare a wire of a passing diameter, electric cardboard or press board, adhesive tape, shrink cambric of the required diameter.

If you have a non-separable stator, then in its grooves it is necessary to make sleeves from a press frame by cutting out blanks along the width of the stator.

Billets are cut out of the press board with a width equal to the stator width and a length equal to the length of the inner groove. By the way, 2 mm must be added to the stator width on each side. After cutting out the blanks, close their edges with wide tape. For the stator of the Makita perforator, an adhesive tape 50 mm wide is suitable.

Stick the blank on one side of the strip of tape, cut. On the second strip of adhesive tape, glue the blanks with the same side, but with a different edge. Your task is to close the edges of the blanks from gaps during winding.

Making fixture strips

To ease the hand winding process, make simple fixtures that are soft metal strips up to 0.8 mm thick. It can be galvanized steel, copper, aluminum. The stripes are z-shaped plates 10 mm wide and 70 mm long.

Fit a heat-shrinkable tube onto the smaller hook and heat over a flame, squeeze the tip of the plate.

Secure the resulting plates with tape on the stator housing.

Winding process

The wire is prepared, the fixture plates are fixed, the data on the number of turns are at hand. Forward!

We put the stator on the knee, start the end of the wire, put on a red heat-shrinkable cambric (it means the beginning of the winding), fix the cambric on the outside of the stator and start winding. By the way, the color of the cambric can be any, you just need to choose a different color for the beginning and end of the winding.

The winding process consists of feeding the wire into the groove with your thumb, inserting the wire by the hook of the fixture plate, pulling out the wire and inserting the plate by the hook on the other side. Most importantly, keep track of the number of turns wound. The winding process is repeated for the second coil.

This is all perfectly visible in the proposed video.

Video:

Everything! The stator is wound. It is necessary to carefully tie the windings, make a reservation.

Stage IV

Stator winding booking process

Reservation refers to the strapping of the stator coils, which protects them from destruction during operation. At high speeds, various vibrations affect all parts, which leads to the destruction of the integrity of the windings, their friction against each other and insulation failure.

It's time to start impregnation.

Stage V

Stator winding impregnation process

The main task of impregnating the stator coils is to obtain a monolithic structure that does not deteriorate over time from vibration. Before starting the impregnation, wooden spacers are inserted into the stator, pressing the coils. Work should be done carefully and carefully.

In ideal conditions, a transformer is needed for impregnation. It is recommended to impregnate the coils under voltage so that the wires vibrate and warm up. This allows the impregnation to flow into all cracks. The voltage on the winding is low, until vibration occurs. It can be easily found by leaning a screwdriver against the inner surface of the rotor.

Ideally, use a special varnish and apply it in several layers. You can also use ordinary paint for interior painting of the PF-115 brand. Outflow of 50 g of paint into a separate bowl, dilute it with a solvent to the consistency of water.

Using a syringe, draw up paint and inject in small portions onto the stator coil until it penetrates completely into the middle of the coil. The stator must be warm and connected to an AC power source. It is better to use a transformer as a source, the primary winding of which is powered through a LATR.

Remember to monitor the stator temperature. The hand can hardly withstand the temperature of the case. At higher temperatures, reduce the supply voltage to the transformer using the LATR.

The consistency of the paint depends on the diameter of the wires. The thicker the wire, the thicker the paint. Continue the impregnation until the paint appears below. Turn the stator over and continue impregnation. Leave the stator under the direction until completely dry.

The stator is impregnated and, after cleaning from traces of paint on the inner surface of the stator, is ready for assembly.

Stator impregnation and rewinding:

Video:

Now you can start assembling the Makita puncher. If you think that it is difficult, then entrust the rewinding work to professionals.