Xiaomi’s current electric shavers and their Mijia sub-brand are known for their minimalist design and high sealability, which often baffles users when maintenance is needed. Owners of S500, S300 or Enchen Blackstone series devices often wonder how to access internal components to replace a knife unit or battery without damaging the body. These gadgets are designed without frequent disassembly, but with the right approach and the basic tool, the dismantling process becomes quite feasible.
The main difficulty is the absence of visible screws on the outer surface of the device, as the manufacturer relies on a system of hidden mounts and a tight fit of elements. The rear cover or bottom end cap often acts as a lock of the entire internal filling, and its careless removal can damage moisture seals. In this article, we will discuss in detail the algorithm of actions that will allow you to safely open the case, preserving the functionality of IPX7 and the aesthetic appearance of the device.
Before you start taking action, you need to clearly understand which model you are dealing with, because the design may differ. For example, flagship models with a display, the locking mechanism can be more complex than budget versions with a single indicator. Xiaomi's engineering build involves the use of adhesives and friction joints, so rush is not allowed. Let's consider what tools you will need and how to prepare the workplace for a delicate procedure.
Workplace preparation and necessary tools
The quality disassembly of any equipment begins with the organization of space. You need a clean, well-lit surface, preferably covered with an antistatic mat or just a clean fabric, so that small parts do not get lost and scratched. The main enemy when disassembling plastic cases is brute force, so be patient and specialized tools that minimize risks.
- 🔧 Thin plastic blade or mediator is the main tool for opening latches without scratches.
- 🔧 Thin steel needle or scalpel - necessary for fitting tightly seated caps.
- 🔧 Hair dryer or heating platform – to soften the glue if the cover is planted on a sealant.
- 🔧 Tweezers with thin curved ends - for extracting small screws and working with wires.
Special attention should be paid to the condition of the battery before work begins. If the razor was working intensively and has signs of overheating, let it cool completely. Li-ion batteries are sensitive to mechanical damage, and puncture of the battery body with a sharp tool can lead to fire. So all manipulations are carried out as carefully as possible, controlling the pressure on the body.
⚠️ Warning: Before disassembly, be sure to completely discharge the device or, conversely, charge it to 100% to eliminate the risk of short circuit when disconnecting the plumes, if the design involves working under voltage.
Some models, such as the Mijia Electric Shaver S500, may have hidden screws under decorative stickers or rubber inserts on the end. Carefully inspect the bottom of the device in sidelight. If you find a hole, it is likely that there is a Torx screw or cross screw hiding underneath, which must be unscrewed first. The absence of visible screws indicates the use of a clips latch system.
☑️ Checking disassembly readiness
Design analysis and search for hidden fasteners
Understanding how your razor is assembled is 90% of the success. In Xiaomi devices, two types of build are most common: either the back cover is part of the main body and is removed with it, or it is a separate removable element fixed by a thread or bayonet connection. Visual inspection of the joints will help determine the type of connection.
Swipe your nail or thin plastic tool along the junction line of the back cover and the main body. If you feel a light backlash or hear a characteristic click when pressed, it may be that the lid is held on a friction-fit. In more complex cases, such as the Enchen series, the lid can be glued around the perimeter to ensure the claimed water resistance.
Notice the presence of rubber rings or seals. They often mask screws or serve as an additional lock. If you see a rubber plug in the charging port, carefully remove it. Sometimes there are fasteners underneath. It's also worth checking if the bottom part is threaded: try to carefully, without undue effort, turn the lower end part counterclockwise.
Secret marks on the hull
If the visual inspection failed, look at the model specifications. Some of Xiaomi's engineering solutions involve the use of magnetic mounts for the rear panel, which is found in premium rulers, in which case the lid is removed by simple pulling, but requires a confident and uniform effort not to skew the mechanism.
Dismantling process: step-by-step instructions
Start by heating the bottom of the case if you suspect glue. Use a dryer at medium temperature, warming the end for 30-40 seconds. This will soften the adhesive layer and make the plastic more elastic, which will reduce the risk of cracking when exposed to the tool. Do not overheat the device, so as not to damage the internal electronics or battery.
Take a thin plastic blade or mediator and insert it into the junction between the back cover and the body. Move around the perimeter, slowly and smoothly opening the latches. Don't try to open the lid from one side to the end; it's better to go around in a circle, gradually increasing the gap. If you hear a crack, stop and try to warm up the resistance again.
- 🛠️ Insert the tool into the joint and twist slightly to create an initial gap.
- 🛠️ Move along the seam, snapping the locks in a circle.
- 🛠️ If you have screws, unscrew them before trying to remove the lid.
- 🛠️ If the cover sits tightly, use a suction cup for gently pulling.
In models where the back cover is part of the knife block extraction mechanism (as in some versions of the Mijia S300), dismantling may require simultaneous pressing of the side buttons of the retainer. Explore the side faces of the device: the presence of slots or indentations indicates places for the tool to grab. Carefully tuck these places, while trying to remove the cover.
⚠️ Warning: Never use metal screwdrivers to tuck in plastic parts without protective tape, as this is guaranteed to leave deep scratches and can crack the fragile part. ABS-plastic.
Once all the latches are freed, the lid should be easily separated. If you need a force that exceeds reasonable, then you missed some locking element or screw.
Features of disassembling popular Xiaomi models
Xiaomi's different razors have design features that are important to consider. For example, in the Mijia S500, the insides are often accessed through the bottom end, where the charging port is located. whereas in the Enchen Blackstone 3, the mechanism can be hidden under a decorative insert. Knowing these nuances will save you time and nerves.
The S500 series is characterized by the use of hidden screws under a bottom sticker or rubber leg. Once unscrewed, the lower part of the body moves downwards, opening up access to the battery. In wirelessly charged models, the back cover can be glued more aggressively, requiring careful warming up and the use of thin blades to trim the glue.
| Model razor | Type of lid attachment | Location of screws | Difficulty autopsy |
|---|---|---|---|
| Mijia S500 | Latches + screws | Under the end plug | Medium |
| Enchen Blackstone 3 | Tight landing | Absent. | Low. |
| Xiaomi S300 | Carving/Bayonet | Absent. | Low. |
| Mijia S700 | Glue + Latches | Hidden inside | Tall. |
Premium models like the S700 often use a ceramic knife and a more sophisticated sealing system, where the back cover can be non-removable in the classical sense, and the battery is accessed through the disassembly of the entire body at the seam, in which case the leakage during disassembly is almost guaranteed to lead to loss of IPX7 moisture protection, which requires subsequent high-quality gluing.
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Accurate knowledge of your razor model is key to successful disassembly, as the mounting methods of different generations of Xiaomi are radically different.
Replacement of the battery and maintenance of internal components
After successfully removing the back cover, you will be able to access the heart of the device, the battery and the control board. Most often, users are looking to replace the battery, which has lost capacity over time. Xiaomi razors usually have standard sizes, such as 14430 or 14500, but may differ in the type of connector.
The battery can be connected through a connector or soldered directly to the board. In the first case, it is enough to carefully disconnect the connector with tweezers, pulling a chip, not the wires. In the second case, you need a soldering iron and electronics skills. Be careful: lithium batteries are afraid of overheating, so soldering should be done quickly using flux and solder with a low melting point.
- 🔋 Check the voltage of the old battery with a multimeter before recycling.
- 🔋 Make sure the new battery has identical dimensions and connector.
- 🔋 When soldering, isolate the soldering iron sting from other components of the board.
- 🔋 Do not allow the battery to close the plus and minus with metal tools.
In parallel with the replacement of the battery, it is recommended to conduct a revision of the knife unit and clean the internal cavities of shavings and skin fat that may have entered through the shafts of the knives. Use compressed air and a soft brush. Also check the condition of the silicone seals; if they have lost elasticity, they are better replaced or lubricated with silicone lubrication to restore tightness.
⚠️ Warning: When installing a new battery, strictly observe polarity. Misconnection can cause the charge controller to burn or all razor electronics to fail.
If you change the battery, make sure it's securely locked inside the case. The original build often uses double-sided tape or special plastic locks. If you don't lock it, it will vibrate the battery when the motor is running, which over time can damage the contacts or the power supply itself.
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Use original batteries or quality protective board (PCB) counterparts to avoid the risk of bloating and ensure that Xiaomi’s charge controller works properly.
Assembly of the device and checking leakage
Reverse assembly requires even more care than disassembly. Make sure all the plumes are packed into their channels and not be clamped by the body. Trains are the most fragile elements, and damage to them during assembly is more common than during disassembly. Make sure that the power button and other controls are accurately hitting the openings of the case.
When installing the back cover, first hook one side, then sequentially press the rest until the characteristic snap of the latches. If you used glue, apply a new layer of special electronics sealant glue (such as the B-7000) with a thin layer around the perimeter. Let the glue dry slightly (2-3 minutes) before the final docking, and then tightly press the parts.
After assembly, take your time to wet the device. Let the glue polymerize during the process. 12-24 First check without water: turn on the razor, check the charging and operation of the engine. Only when you make sure that you work properly can you test waterproof, although full sealing of the factory level after opening is not guaranteed.