How to choose a wrench for DIY car repair
Content
Self-repairing a car is not easy. In cars with high mileage, something always breaks down, and they have to be repaired. Most modern cars are equipped with sophisticated electronic systems, which sometimes makes even the usual seasonal wheel change a serious problem.
As for budget cars, say, from the beginning of 2000, many units in them can be repaired on their own. However, without the proper tools, a self-taught mechanic will either spend a lot of time with repairs, which will be carried out at the service station in 5 minutes, or will be injured.
Consider one special tool that makes car repairs more enjoyable, safer, and faster. This is a wrench. First, let's talk about why it is needed, and also what is the principle of its operation.
What is it for and how does it work?
The name itself suggests that this tool is designed to twist nuts and bolts with matching caps. A wrench is one of the main types of tools that must be found in the toolbox of any motorist.
All connections of auto mechanisms are made according to the type of bolt / nut. Since in the process of driving these clamps are affected to one degree or another by vibration, they periodically weaken, and they need to be tightened. When even an elementary engine oil change is made, the same wrench is required to drain the old grease.
The impact wrench is a versatile tool. Outwardly, it looks like a drill. Only on the rotating part it does not have a chuck, but an adapter for connecting a nozzle (a 4-sided pin on which a replaceable head is put on). There are also models in which the nozzle does not change.
The rest of the device is almost identical to the drill - the pistol body, the trigger button on the handle, etc. Depending on the model, the tool uses different sources of influence on the rotating element. This can be electricity, the power of the air pumped by the compressor, etc.
The mechanism is equipped with a return spring that allows the shaft to rotate in the opposite direction of rotation of the motor shaft or other drive mechanism. Thanks to this property, the mechanic can set the tightening forces so as not to break the thread. However, manufacturers of auto tools may use other mechanism designs.
This tool makes it easier to handle boiled bolts or nuts. Its mechanism is designed in such a way that the torque is supplied to the driven shaft not through a rigid coupling, but through a device that provides an impact effect (similar to the operation of a hammer drill). Thanks to this, the boiled thread breaks off without the need for excessive efforts, which is why repairmen are mostly injured - the key jumps off, and the person hits the machine with his hands.
Types of devices and their differences
There are two types of impact wrenches in total. The first type is percussion (the effect is like a hammer drill), in which the twisting occurs in jerks. The second is unstressed. It only rotates the head.
The second type of instrument belongs to the category of amateur. It's easy to work with him. The impact model has a high torque, which allows it to be used in professional repairs. For example, tire changers use such modifications.
In addition, the devices are divided into four types according to the type of drive. Here are their main differences.
Electrical (network)
These wrenches are mainly impact wrenches. They have enough power to smoothly unscrew or provide a high-quality clamping of most connections in the machine. Due to the presence of a wire, the electric wrench does not have great mobility, and if used carelessly, the cable cores break.
They do well with complex connections that require a lot of leverage when using a regular key. Unscrewing is provided by impulse operation of the electric motor. Most models are equipped with an adjustable tightening force. In this case, it works like a torque wrench.
Rechargeable
Instead of power from the mains, the cordless impact wrench uses electricity from a removable power source. The advantage of such a model is its mobility. The master can get to any part of the car without using an additional extension cord. It copes well with most small tasks in domestic conditions, as well as with minor car repairs.
The biggest drawback is the battery capacity. When it is new and well charged, the tool handles tight connections that require 500 Nm of force. But even in this case, after the first boiling nut, the charge decreases, which is why you have to recharge the battery.
Pneumatic
Any professional garage will have this wrench modification. The pneumatic tool is powerful, and the tightening force can be up to three thousand Nm. The operation of the mechanism is provided by the force of compressed air, which is supplied from a reservoir connected to the compressor. The tightening force is regulated by a valve located on the handle of the device.
Most often, the tool body is made of metal to ensure rapid cooling. The flow of compressed air drives the shaft on which the head is fixed. Most models do a great job of any size of nuts used on car wheels. True, the price of such a tool will be high, and for its operation, you additionally need to purchase a compressor unit.
Hydraulic
The hydraulic option is the most powerful of all. It is used in industrial plants. The torque in such models is already measured in tens of thousands of Nm. For a regular garage, any of the listed models is sufficient.
The tool is powered by hydraulics - oil or other working fluid is pumped in by a pump. It drives a turbine, to which a shaft is attached with a corresponding nozzle.
Here is a short video on how an air impact wrench both twists and hits the nut at the same time:
Type of food
A little more detail on these modifications. The electric tool is powered from a regular household electrical outlet. It does not need to increase the line power (220V is enough). This modification is best suited for motorists who service a single vehicle. It is especially necessary to work with such a tool in rooms with a high risk of fire. These impact wrenches use a conventional brush electric motor that produces sparks.
Battery-powered modifications have one more advantage besides mobility. More expensive models do not use a brushed motor, so they are perfect for rooms with a high fire rate. Professional wrenches of this type can even cope well with 32 size hub nuts. It is more practical to choose the option with two batteries in the kit, or purchase an additional power source separately. This will shorten the repair time when the battery runs out.
For most garages, it is more practical to purchase a pneumatic model. Most services already have compressor units by default, so there is no need for additional waste with the purchase of a tool. But for the real owner, the compressor will be practical in everyday life and for other work, for example, to paint surfaces with a spray gun, etc.
Shape, materials and comfort
In addition to the classic pistol-type nutrunners, there are also angular modifications. They are in the form of an ordinary hand ratchet, only they are connected either to a compressor, or they are powered by electricity. The advantage of such modifications is their convenience. It is enough to grip the tool with one hand, as we usually hold a wrench.
Another variety is the so-called straight wrenches. They are mainly used on conveyors where a worker assembles large assemblies without leaving the production line. The advantage of such models is in their maximum torque.
Some models reach 3000Nm and more. True, such wrenches will cost a lot - around $ 700. Since the tool is designed for clamping large nuts and bolts, it has two handles so that the wrench does not break out of your hands.
As for the comfort and ease of use, from the practical point of view it is worth stopping at the model with a rubberized handle. It is easier to hold it in your hand, even with gloves. Basically, such devices are made of impact-resistant plastic or metal. The metal counterpart is more reliable and is able to withstand the active work of a sloppy master.
Additional functionality of devices
Here's what to look for when choosing a new impact wrench:
- Torque is a parameter that determines the forces with which the part will be twisted. Naturally, the value of this parameter affects what kind of work can be performed with the tool. The more powerful the engine is, the more expensive the tool will be. To determine this parameter, it is worth considering that to unscrew a conventional wheel bolt, you will need a tool with a torque of 200 Nm. If a Chinese model is purchased, then the parameter specified in the instructions is often twice the real indicators. When deciding on a wrench model, you should pay attention to the power change function. It will come in handy when small nuts are tightened (so as not to break the thread).
- Impact mode - the operation of the tool with impulses that simulate blows with a hammer on a key. This function allows you to tighten the threaded connection with less effort. It does not work in the same way as the hammer mechanism in a drill or hammer drill. Its difference is that the head rotates in jerks. Basically, this mode is required to rip off a rusty nut. The decent DeWalt DCF899P2 impact wrench, which is powered by a battery, entered this category.
- Backlighting is another option that can be useful when repairing a car. When the technician is in the inspection hole, even a portable light may not help to see the desired mount. A flashlight installed in the area of the rotating head will help you see if the mount is spinning enough or not. The only caveat regarding this option is that only modifications with a battery are equipped with backlighting. For the rest, the manufacturer did not provide for it.
- Protection of the motor against overloads - such an additional function should have an electric model, since in a pneumatic analogue the drive is carried out by air pressure. An overload lockout automatically shuts down the tool to prevent its motor from burning out. Unfortunately, most cordless wrenches are equipped with such a system. As for network analogs, there are only a few of them. The reason is that this type of interlock is used on brushless motors, and network models rarely have such a drive.
How much do they cost (best models)
The cost of a wrench depends on its type, speed and maximum torque. The higher these indicators, the more expensive the tool will cost, but the task with which it can cope can be much more difficult. A conventional battery variant with a 12-volt battery and a tightening force of about 100Nm will cost a minimum of $ 50.
An electric analogue, the power of which is 40W, and the torque is 350Nm, will already cost about 200 USD. The model is made of impact-resistant plastic, the handle is rubberized. Such a wrench will be protected from overheating. Great for those who often perform maintenance on a passenger car.
The best among non-professional equipment will be models from such manufacturers:
- Cordless and electric impact wrench from the German manufacturer Bosch (GDR). Despite the high price tag (it starts at $ 200 and up), even the battery-powered model does a good job of handling many connections in the car.
- An impulse-type electric tool manufactured by a domestic manufacturer (ZUBR). Many novice masters opt for it. Its price is from $ 80.
- One of the most expensive impact wrenches is Hilti. Model with a removable battery, it comes with several standard attachments and an extension cord for hard-to-reach places. The cost of such a tool starts at $ 400. This modification works in a pulse mode, which saves battery power.
- Among pneumatic models, Jonesway JAI-1114 has proven itself well. In it, the maximum torque reaches 1356 Nm, and the rpm is 900 per minute. The cost of such a tool is about $ 180.
- The Makita TW140DWAE is another good cordless impact wrench that can handle minor car repairs just fine. The set includes two 12-volt batteries, bits with replaceable heads in the case. Despite the small torque (140Nm), it has an impact mode (the number of impacts reaches 3200 per minute). It is adjusted by pressing a button.
- The Inforce PW720 is a pneumatic model that can withstand heavy use. Great for professional tire changers and service stations. The body is rubberized, so that the tool is not afraid of falling onto concrete. The torque is 570Nm and the price starts at $ 80.
For an ordinary car workshop, you can purchase a pneumatic modification with a compressor unit. The compressor can also be used for pneumatic jacks and wheel inflation. If an impact wrench is chosen for a personal garage, then an electric shock model will be more than enough. The load on it at home is not so high that the tool quickly fails.
The only thing is that you should choose products from well-known companies, for example, Makita, Bosch, etc. In this case, the manufacturer gives a good guarantee and provides high-quality service. A this review tellshow to unscrew the door to the VAZ 21099 for a beginner if there are no suitable tools at hand.
Watch a short video on how the cordless impact wrench works (which allows the head to rotate with pulses):
Questions and answers:
Which impact wrench to choose for your garage? It depends on the work being done. For household needs, an electric wrench will be enough. A pneumatic analogue will be needed already at a professional service station.
How to choose an electric garage impact wrench? The power of professional models starts from 1.2 kW. Excessive torque is fraught with breakage of the thread, and insufficient torque is fraught with weak tightening of the nuts.
How much power is needed for a garage wrench? In domestic conditions, it is enough for an electric wrench to have a power of about 1000 W and a torque in the range of 300-400 Nm. Such a tool will cope with any task.
