This is the new right angle Electric tools. It has a right angle for ease of use, or to fit into tight areas.
Time and technology has changed the way many cars are put together these days, there have been many new introductions for example like plastic clips, adhesive and Velcro, replacing trim nails and screws that normally held panels together in the past. There is still the use of bolts when assembling mechanical components, but even some of these has changed. Today, on major assemblies, torque to yield bolts are used in engines.
These bolts stretch to the yield point when tightened; the bolts are often used when exact clamping loads are needed on parts, they can be used on connecting rods, crankshaft main bearing caps, cylinder heads, front engine dampers and even flywheels. Torque to yield bolts will no doubt be used if the shop manual indicates a bolt needs to be discarded and replaced with a new one.
This can become expensive and a total waste of time if you have to buy new bolts all the time. Too many these old bolts may still look usable but beware looks can deceive, if using old bolts it may cause engine failure an expense nobody wants. Through the process of tightening bolts it pulls them to their elastic limit due to stretching, that's why new ones are needed to give maximum force on today's engines.
It is easy to understand if you tighten a bolt to much then the harder it is for it to become accurate on a clamping load. Friction occurs when tightening bolts these are like a ramp, when turning this has to slide against another thread or ramp in the bolthole. The tighter it goes the harder it becomes to move or push up the threads ramp.
When stationary the term used is stiction as against friction, as the bolt becomes tighter it is the station that will affect a torque reading. People may use lubrication to help threads slide easier but the quality between one lubricant and another can vary. It is far easier to follow manufacturer's guidelines for the best type of lubricant that is needed for the bolt when tightening. This is important because if you use the wrong lubricant it may become too tight or not tight enough.
There are several stages to follow when tightening torque to yield bolts this is done using both a torque and turning angle. The first step is to tighten the bolt to a low torque specification, this is done to ensure even clamping load is in place when parts are assembled. The second stage is to tighten again slightly to the higher torque stage. This will still allow enough friction and stiction on the bolt threads as the torque is tightened very little. The normal procedure after this is too turn each bolt a specified number of degrees normally two to three steps. As an example, the bolt might be turned 90 degrees, and then another 90 degrees until a further 70 degrees has tightened the bolt sufficiently. This will ensure the clamping force that has been exerted by the bolts is both accurate and even.
Special tools are used that can measure the degrees a wrench or bolt has been turned, these are low cost protractors that has a movable pointer, whilst some tools use electronics when measuring a turning angle these can cost several hundred dollars. These two types both work well and though the electronic one is more expensive it actually can make the job go faster.
Some may ask the question why are the torque to yield bolts needed now? When perhaps they weren't needed in the 1960's or 70's. The answer to that question is quite simple in that engine materials are different now. For example, the aluminum cylinder heads expand differently to cast iron blocks. When an engine warms up, all the parts bolted together have to be able to slide on their gaskets or move against each other. Because of the elasticity in the torque to yield bolts allows movement between the parts but still maintains even sealing and clamping loads.
Engine parts today are a lot lighter than decades ago, the heavy cast iron parts was able to take variations in torque without failing. Aluminum alloys and thin wall castings that are used today need accurate torque if this is incorrect then leaks or warping can occur.
Today the design of engines is changing due to the need of even clamping forces, the car manufacturer Ford have prototype engines where bolts which hold the cylinder head on can go all through the engine block threading into the bottom casting which holds the crankshaft. It's hard to imagine that only a few bolts can hold a complete engine together. This would definitely change the way engines where assembled and disassembled in the future.Bolt Tightening Technique
The cordless impact wrench is quickly gaining in popularity among professional mechanics and the hobby mechanic as well. You may be thinking "I already have a cordless drill that I use for impact applications, why do I need a cordless impact wrench as well?". I thought the same thing. The first difference is on the inside. A cordless drill creates continuous in-line torque. A cordless impact wrench employs an internal spring-loaded pulsating cam to create rotational torque. This creates the "impact" force that loosens a nut. It is the equivalent to banging a wrench with a hammer to loosen a rusty nut only a lot faster. Unlike a cordless drill - which creates continuous in-line torque, a cordless impact driver uses an internal spring-loaded pulsating cam and gear mechanism to create rotational torque or the "impact" force.
Another big difference, is the lack of reactionary torque. Reactionary torque is what you experience with your cordless drill. You have to use brute force to keep your drill from spinning the opposite direction in your hand. With a cordless impact wrench, that torque is directed to the nut not your arm. You can easily hold this tool in one hand and let the cordless impact do all the work. No more pushing down on the tool to drive that screw. These tools are also smaller and lighter than a cordless drill. For example a DeWalt cordless impact wrench is about 35% the size of its comparable cordless drill. This feature makes them perfect for those overhead projects and reaching into hard to get to spaces.
The next time your start that big deck project in the backyard, leave the cordless drill in the box and grab your cordless impact wrench. Your arm will thank you at the end of the day.Cordless Impact Wrench - Not the Same Tool as Your Cordless Drill
Impact wrenches, also known as torque wrenches and air wrenches are a useful tool for all sorts of hands on jobs. They are frequently used for auto repair, construction and manufacturing. These wrenches save time and effort and are easy to use.
Impact wrenches work like this:
Inside the wrench there is what is called a hammer. This hammer is spun by the motor until it is moving at a high speed. This generates energy which is then put into place by quickly connecting the output shaft. This creates a large amount of torque.
Tools for use with an impact wrench:
Impact wrenches allow for a variety of impact sockets and other tools. Tools for use with impact wrenches must also be strong to be able to stay intact while being exposed to such high force. These tools are made of high tensile strength metals as to prevent springback which reduces torque. Because of this you must make sure to only use tools made for use with your impact wrench. If you don't you could ruin your sockets or cause injury.
Tips for using an impact wrench:
Impact wrenches are fairly easy and straightforward to use. One tip that is very important for beginners is to remember to never apply too much torque. Applying too much torque can damage whatever you're working on and can also cause dangerous accidents. Whenever I remove tires from a car I make sure to first break the lugs while the car is on the ground before using my impact wrench, and when I'm done, I make sure that I give the lugs a little torque but I hand tighten them to make sure the job is done right.
Maintaining your air wrench:
Maintaining your wrench is just as important as the rest of your tools. Its better to check over and do regular maintenance than to have to buy a new tool. I would suggest that you always check your wrench before use. Take the time to make sure your wrench is clean. Make sure it is properly lubricated with the correct type of oil and that it is applying the correct amount of torque both forward and backward. If not, you should not use your tool until you have a technician look it over and find out what the problem is.Impact Wrenches - What Are They Good For and How to Use Them
First patented by Solymon Merrick in 1835, the wrench is also commonly called spanner in British English. Since 1835, it has had an almost universal presence across the world, due to its simple yet effective design.
In the following article, I'll run through the factors that have lead up to the wrench's (or spanner; depending on which side of the pond you're from!) ubiquity. Alongside this, I'll also talk about other major varieties of wrenches out there and what they have.
The wrench's simplicity of design is one of the main factors why it has been so widely adapted since it's inception. The simple design guarantees it is easy-as-pie to duplicate and consequently is able to be mass produced efficiently, yet its extreme effectiveness in the design and employment of torque ensures loosening or tightening bolts is an easy process.
The workings of the wrench are wonderfully simple in fact; it acts as a lever, and because of the length of the tool, it reduces the amount of force you need to apply to fasten or loosen the nut. With adjustable wrenches, one of the most commonly found variations of the wrench, the head of the wrench is adjustable within a given toleration so it is able to accommodate a range of nut sizes. Hence, its effective at adapting to a range of situations.
Conventionally, the wrench head is at a 15 degree angle towards the shaft. This facilitates the use of the tool in close quarters.
Another commercially widespread sort is the socket wrench, the ratchet wrench being the clear winner here. These are normally used by mechanics, as they allow for one way ratcheting - a quick process that decreases the time it takes trade people to do certain tasks like unfastening car wheels.
Finally, you might also be familiar with the Allen wrench (commonly called the Allen key), which are cheap and easily reproduced pre-fabricated wrenches of a individual measurement. Their hexagonally shaped head is not changeable, and they usually accompany specific products that require them for maintenance.A Brief Overview and History of the Wrench
The rear drum brakes on Jeep Cherokees are generally reliable and long lasting. While swapping to disk brakes is a popular modification, the rear drums do a fine job of stopping when they work properly.
One common problem as the brakes age is that the wheel cylinder leaks. The wheel cylinder has two pistons that press out on the brake shoes when the pedal is depressed. The two pistons have rubber cups on them that will wear with age. Also, water can contaminate the fluid and cause the lining of the cylinder to rust.
There are several different wheel cylinders used so make sure you get the proper replacement before disassembling the Jeep. The cylinder for the 9" brakes is different from the one for the 10" brakes and the one used for antilock brakes is different from the one used for non antilock.
Begin by lifting the Jeep and supporting the rear axle. Remove the wheel and tire.
Using a 3/8" line breaking wrench, loosen the brake line where it connects to the wheel cylinder. If the line is stuck, try tightening it a bit before loosening it. Heat can help if it is severely stuck. Use care not to damage the metal line. Use a pan or a rag to catch the brake fluid that drains out.
Remove the two 3/8 headed bolts that hold the cylinder to the backing plate. Remove the brake drum. Loosen the brake shoes slightly if necessary.
Using a brake spring tool, remove the two upper brake shoe springs. Pull the front shoe slightly forward and slip the wheel cylinder out around the axle flange. Clean up and fluid that had leaked into the brake drum.
Slip in the new wheel cylinder. Install the two retaining bolts. Reseat the front brake shoe. Replace the springs using the other end of the brake spring tool. Take care to ensure the cable for the automatic brake adjuster is routed correctly and has not fallen out of place while the tension was off.
Reconnect the brake line. Reinstall the brake drum and adjust the tension.
Add brake fluid to the master cylinder to replace what drained out. Bleed the brakes by having an assistant depress the brake pedal while you open and close the bleeder screw.
With the bleeder closed, have the assistant pump the pedal a few times and then hold it depressed. Open the screw and allow fluid to come out. Close the screw and have the assistant repeat the process. Repeat the process and have the assistant note the firmness of the brake pedal as you observe the amount of air in the expelled fluid.
Once the fluid runs clear with no air, tighten the bleeder screw and install the protective cap. Reinstall the wheel and tighten the lugs to the proper torque. Lower the Jeep and top off the master cylinder before driving.How To Replace a Leaking Rear Wheel Cylinder in a Jeep Cherokee