First of all, why should you use an impact driver? You might think that if you own a hand drill or drill press that there is no need for an impact driver. However, that is not the case. An impact driver is suited to a specific set of tasks and is extremely versatile. If you're thinking about upgrading your tool arsenal after buying a standard hand drill, an impact driver is probably the most essential next tool to get. Impact drivers are fantastic at screwing in planks at high speed, putting decks together, screwing plywood down, and much more. Essentially they're ideal for a job where you need to drive a screw/bolt into some kind of wood.
If you haven't seen an impact driver up close before, at first glance you might think that it's just a drill. The difference in appearance is quite subtle and can be deceiving. One key difference is in how you load the bit. A drill uses a chuck that essentially locks down onto the drill bit and is hand tightened. Where as an impact driver uses quick change collet locking mechanism, that holds onto hex shank driver bits. You can't use a drill bit with an impact driver, unless you convert the drill bits with a hex shaft. they're designed primarily to be used with screws and bolts. They offer much more torque than a regular hand drill, which makes the work much more comfortable for your wrists and arms and can get jobs done where a normal handheld drill would stall. Another important benefit is that an impact driver is much less prone to stripping out screws.
Impact drivers are pretty self explanatory to use, however there are somethings you you aught to keep in mind so that you don't have to learn them the hard way. So here are the basic steps you need to carry out in order to use an impact driver properly.
Make sure the battery is charged, most of the time the battery will be charged when you unbox it from the store. If the battery is not charged make sure the first time you charge it you leave it on charge for the maximum time. Ensure that the impact driver is switched off, and then insert the battery. This is usually done by sliding it into a slot that is built into the handle.
The next step is to insert the bit that you will be using. For safety reasons always check that the shank end of the bit is free from debris and is not damaged. One other thing to note is that you often need a bit holder if you're using a particularly short bit. To insert the bit simply slot it in until it reaches the back of the chuck.
Now you need to set up the tool for whatever job you're doing. First set the rotation for forwards, or reverse if you're removing rather than inserting something. Then you'll also need to select a speed, or gear - which setting you choose will depend on how much torque you need for your job.
Now that it's all setup it's time to switch it on. Once it's switched on, to use it, squeeze the trigger. it may take a while for you to get the hang of using it if it's your first time, so it's a good idea to put in some practice to get the feel for it before you go straight into working on the job. Adjust the speed/gear as necessary.
Once you're done with using your impact driver, switch it off and put it aside for a minute to let it cool down. Depending on how long you used it for you may need to recharge the battery in preparation for your next use. To remove the battery normally there is a switch which unlocks a latch allowing it to simply slide out. To remove the bit simply grab onto the chuck and pull it, it should slide right out - a much more simple process than removing a bit from a hand drill. At this point you may want to give it a clean, in order to keep it in good shape, after that put it away in your garage or workshop.