Editing Removing stuck fasteners

{{youcanedit}} ==General Advice== *No matter what technique is used, when removing stuck fasteners, you need to pay attention to what is turning and what is not. *There is no general consensus as to whether steady or intermittent pressure is best for removing stuck fasteners. *Keep in mind that fastening hardware stuck together by corrosion is stuck because the corrosion has expanded and tightly bound the fastener. In theory, there should be nothing to stop you finger-tightening the bolt until it's snug or easily loosening a bolt once it has been fastened snugly. In practise, it's often quite hard to turn some bolts or loosen other bolts, even when they are slack. The reason for this is that dirt gets stuck in the bolt threads, and it gets trapped when you start tightening the bolt making it harder to turn. This is a warning sign -- if you can't finger tighten a bolt until it's snug then there is something wrong. If you are trying to put a bolt in, then take it out and clean the threads. If you are trying to loosen/remove a stuck bolt, see if you can access the end of the bolt (opposite end of the bolt head). Put a little grease on the threads before you try again. It's a bad, bad idea to get out spanners early to carry on trying to tighten a bolt that isn't turning smoothly. Even if you get it tightened, that dirt is still in the threads, and it's quite likely that it'll jam the threads when you try to next remove the bolt. Dirt-jammed threads are a pain when you're putting a bolt in. They're much worse when you're trying to remove a bolt. Imagine what happens if the thread is jammed at the far end of a bolt which you're trying to remove. You turn the bolt head, so the top of the bolt is getting pulled out. However, the bottom of the bolt is jammed in place. In this situation, it's quite likely that the two halves of the bolt will seek a divorce. Suddenly, the bolt becomes very easy to turn, because the top half has broken off and isn't under tension any more. The bottom half of the thread is stuck inside some bit of your bike. Good luck getting it out! Remember: bolts should turn smoothly. If they don't, there is something wrong.This means a really stuck bolt will not allow penetrating oils in to do any good. *There are two effective means to break the friction that corrosion has caused. One is through mechanical movement, a proper good whack with a hammer. The other is through differential heating. Making one part expand more than the other. *With heating, bear in mind axles and other important structures may lose their strength if they are heated much above 300 degrees. If you have the oil and grease starting to smoke, then you are in the 300-degree range. *When taking off cylinder head studs, look at the base. If you see erosion into the stud at the block surface, odds are pretty good you will break the stud. * Whatever system you use, once you have a hold of the bolt,stud, or whatever, try rocking it forward and reverse a little at a time. If you can get it to move, it is more likely to come out. An older mechanic said always try to tighten a little before you loosen. Remember, if it moves, you are half way home. Also, brake fluid works great as a penetration oil. If she ain't glowing, she ain't going ==Tighten, then loosen== In some cases, simply tightening the fastener and then loosening it will do the trick. ==Smack it with a hammer== Though this may not be practical for all situations, a stuck bolt can often be broken loose simply by hitting it on the head with a hammer. In such a case, a brass drift may be helpful. Drifts of varying lengths can be made from brass bar, and used to access hidden bolts. Brass is used because it's softer, and thus less likely to damage the head of a fastener(However the problem with brass is it will absorb some of the shock of the blow from the hammer, so one may need to use a melt drift for maximum shock to the bolt). Brass hammers are also available and one about 3 or 4 lbs. in weight is good for this. If I could have only one chemical tool, it would be "Liquid Wrench". Note that when trying to loosen rusty parts, it's important to first remove as much of the rust as possible with a wire brush. Once it's as clean as a wire brush will get it, apply Liquid Wrench, then give the piece repeated light taps with a hammer for ten or fifteen seconds; this helps work the Liquid Wrench into the crevices. Wait two minutes, then repeat the Liquid Wrench/tapping procedure. After repeating the procedure 3 or 4 times, THEN try to loosen it with one swift blow. Sometimes it won't work, but the majority of the time, your patience will allow you to not only remove the rusted nuts and bolts, but to possibly even reuse them. Many people recommend "PB Blaster", which led to me trying it - it did an excellent job for me. An overnight soak-in is an important step. ==Smack it with a hammer #2== This method is useful when dealing with a bolt that is rusted very tightly. A lot of people will get a wrench or ratchet and push against it with a steady force. Doing this will more than likely break off the bolt head of a rusty bolt. The best thing to do is to get a wrench or ratchet on it, and either hit it with your hand or a hammer several times. The sudden force will break the bolt loose with less of a chance of twisting off the head. If you can get to the nut, try hitting each flat of the nut with a drift punch and ball pein hammer. Some times a home made impact wrench will work, get a cheap wrench that fits tight and hit it with a hammer watching carefully that it isn't coming off the fastener. It's important when loosening this way to use a tight fitting wrench as a loose fitting one will round the bolt head. ==Tap it for a few minutes== Lightly tap on rusted fasteners for several minutes, apply a little penetrating oil, lightly tap a little more, and remove the rusted fastener. ==Metric Method== Hammer a close-fitting metric socket tightly on a SAE nut, or vice-versa. Then use breaker bar socket wrench (or longest you can fit in a cramped space) to turn it. I've seen a product that works basically the same way, but the inside of the sockets are lined with sharpened flutes that are also angled to dig further into the rusted nut or bolt as you turn the wrench. These are called metric sockets, and bite extremely well into round and rusty bolts and nuts, as the flutes are sharp and point counter clockwise. Think of what you would get if you made a mold of an extractor drill bit. ==Hot and Cold== This method uses alternating heating and cooling. The resulting expansion and contraction is thought to break a fastener loose from the grip of rust. #With a welding torch, a hand-held propane torch, or a combination MAPP gas/oxygen torch kit, heat up a bolt head until it turns red. #While it's still red-hot, squirt it with water. #Repeat the heating and cooling process again with the torch and water. When using the "Hot and Cold Method" be sure to follow proper safety procedures. Specifically: *Wear proper safety attire including welder's gloves and safety goggles. *As with any time you use any flammable ignition sources, have a fire extinguisher within arm's reach. When using the 'Hot and Cold Method', care should be taken to ensure that only the bolt is heated. If the nut is heated and cooled, the nut will likely become seized tighter. When using this method use this Hot and Cold method FIRST... If you use any type of penetrating oils, they tend not to let the water do it's thing when the hot and cold method is used. Please remember heat, & then use the water... several times. I think the water becomes steam which has plenty of penetrating power to get in tight places. You never heard of penetrating oil engines, but everyone has heard of steam engines. .. Too much heat will destroy the temper of the bolt. Important bolts (brakes) should then be replaced with new as the untempered one if reused could fail. ==The heat and paraffin wax method== #Heat the bolt with a torch. #Touch the threads with paraffin wax. Ensure that the bolt is situated such that the wax will run down into the mating threads. #Remove the bolt. ==The weld-on-a-larger-nut method== #Place a close-fitting washer over the top of the bolt to protect surrounding material. #Take a nut that is larger than the actual thread of the broken bolt, and weld it to the broken bolt. #Weld in short bursts until the weld fills the nut. This will heat the bolt but not the surrounding material. Using a 6011 welding rod in a stick welder has been reported to work well. #Let the welded nut cool completely without using any water or spray. The bolt will contract and break the grip of the rust. Some more info on welding on nuts. A tig welder is the welder of choice. It is critical to put some penetration oil like Kroil (and not WD-40) on as it cools just low enough for the oil to not just boil off. This will draw oil into the hole. This is the only time I have seen penetrating oil actually penetrate a stuck bolt. For more information refer to this web page http://idisk.mac.com/forever4/Public/pages/studremoval.htm ==Penetrating and lubricating oils== Penetrating oil is an extremely low-viscosity oil that can penetrate into the area between threads on a fastener. A stuck fastener is often heated, sprayed with penetrating oil, and then tapped with a hammer. Some comments on penetrating oils. WD-40 is not a penetrating oil, it is a corrosion preventative. There is problem with the idea that penetrating oils can penetrate rusted together parts. I have done some testing. For a whole week I put Kroil on a head studs. I than pulled one stud from the head that felt like it wanted to come. As I suspected, it was dry. If the bolt is free enough for penetrating oil to seep through then it will come out without any oil. If you really want to get studs out you need to use shock (hammer hits) and or careful application of heat cycles. Some penetrating oils that are recommended by hotrodders: *[http://www.bilthamber.com/ferrosol.html Ferrosol] *[http://pbblaster.com/store/moreinfo.cfm?Product_ID=1 PB Blaster] *[http://kanolabs.com Kroil] *[http://www.wd40.com WD-40] *[http://www.armorholdings.com/productsdiv/break_free.asp Break Free] *[http://www.gunk.com/lubricants.asp Liquid Wrench] *Diesel oil/fuel. Apply and allow to soak for period of time. Then strike head of bolt (if practial) with hammer blow. ==Special tools== *Flameless heat tool useful for removing rusted or broken fasteners: [http://www.theinductor.com/ The Inductor]. *Left-handed drill bits, or screw extractors, can be used to remove many fasteners. *For stubborn nuts, try a nut splitter. It will crack the nut without damaging the bolt inside. *An impact driver can be used to loosen frozen nuts or bolts. Hand-held impact drivers typically have slotted and Phillips headed bits, as well as a socket fitting. The bit or socket is placed on the stuck fastener, and the other end of the impact driver is struck with a hammer. The impact of the hammer strike loosens the fastener, the downward force keeps the bit in its place, and the impact driver turns the force of the hammer strike into a sudden torque on the stuck fastener. *[http://www.sears.com/sr/javasr/product.do?cat=Hand+Tools%2C+General+Purpose&pid=00952166000&vertical=TOOL&subcat=Bolt-Out%2C+Taps+%26+Dies&BV_UseBVCookie=Yes Craftsman 10 pc. Damaged Bolt/Nut Remover Set, Low Profile Bolt-Out Sears item #00952166000]. They are useful for when the bolt head is rounded off, or there is no room to beat a socket or wrench on to it, or when a torch is not available. *Another good brand of bolt extractor is Extractor, has a little bit more "bite" than the Craftsman and Irwin ones ==Tips for broken-off bolt heads== *If enough of the bolt remains, try to grab it with locking pliers or a pipe wrench. *Try to saw a groove in it, so that a flat-head screwdriver can be used to turn it. Use an impact screwdriver if you have one, it will work a lot easier. *Take a 12-point socket that is just larger than the shaft of the bolt, and beat it down onto the bolt with a hammer. Turn it out with a ratchet. When finished, put the socket in a vice, and tap out the broken bolt. *If a bolt is broken off below the surface, build it up with a welder until there is enough to which to weld a nut. If this breaks off try it again, this method is the best, the heat and cool cycle of the tig weld will loosen the fastener in the stuck piece. I have also have had good luck by center punching the broken bolt and using a left hand drill bit about half the diameter of the bolt and as it is drilling most of the time the bit will bite and spin the broken bolt out. ==Miscellaneous tips== *Weld a piece of metal to the top of the bolt, to use as leverage when loosening. *If the slot of a round-headed screw is stripped, file two flat edges in it. Then, it can be turned with an adjustable wrench. Or, use a hacksaw to file a new slot at a right angle to the existing one. *Six-point sockets will grip better on hex nuts and bolts than 12-point sockets. *Drill and tap the bolt to run another, smaller bolt down the center. A bit about half the diameter of the headless, stuck bolt is usually sufficient. Use a jam nut on the small bolt and lots of penetrating oil. *If it is a stripped screw, either slotted or Phillips, try using a dab of valve grinding compound on the tip of the screwdriver. The valve grinding compound will help with friction to hold the tip onto the fastener when turning. *Use a piece of tubing that fits in the bolt hole (OD) with the center (ID) the size of the drill bit. This will keep the drill bit centered in the bolt, when you use the EZ out. *Where access allows, put a box end wrench over a stripped nut or hex bolt head, then use a center punch on the corners of the hex to spread the metal and wedge it in the wrench. *If the bolt or stud breaks off below the surface, try this method. Using a high grade bolt of same size, grind off the threaded end until the bolt will fit into the hole and touch the broken bolt. Using an electric welder, clamp the "electrode" bolt in the stinger. This works best if someone is there to help you by turning the welder on and off. With the stinger bolt inserted into the broken bolt hole and firmly against the broken bolt, have the power turned on just long enough to fuse the stinger bolt to the broken one. You might want to practice this technique on the bench to get the power and timing right. Once they have cooled for a few minutes, but are still hot enough to burn skin, place a wrench on the slave bolt and turn them out. *For removing stubborn Phillips-head screws, wet the tip of the screwdriver or screwdriver bit, a little bit of spit will do, and dip the bit into a bit of abrasive cleanser - like Comet or Ajax. Use enough to cover the tip of the screwdriver. The abrasive in the cleanser gives the tip of the screwdriver a little added "bite" and it's less likely to slip out of the screw. *Intermittent pressure, such as an impact wrench seems to be better suited to this job. A device that we built that works on screws that some one has stripped out the head. Get an aircraft rivet gun (note: not a tubing cutter, they're to fast) that has less than 2000 b.p.m. (blows per minute). Get one of the rivet gun sets, and weld a piece of hex stock 3/4" to the working end of the set then weld an apex tip holder to the hex stock ( of course you need an air compressor 100lbs is just fine) put a Phillips tip in the apex holder (prior to that grind a little off the tip as they usually are slightly too long; this will allow the tip to drop farther into the screw head so it will pick up what is left of the flutes in the head). Put the whole thing together and insert the tip into the screw head slowly pull the trigger on the rivet gun, while at the same time put pressure on the box end wrench you have installed on the hex part of your tool, making sure to keep pressure on the gun handle so it won't jump out of the work. One more word of caution -- even though this works almost 100% of the time it is possible (if the screw is into a plate nut) to drive the plate nut off its mount. *If you break off the head of the bolt, grind the remainder out with care using a TrueBite carbide bit and a high-speed rotary tool (Dremel MotoTool or some such) - see http://www.truebite.com/remove/ for details and instructions. *Besides the Comet cleanser tip, another way to give a screwdriver more grip on a screw head is to dip the tip of the screwdriver into a little valve grinding compound, then apply the screwdriver to the screw head. Works well anywhere you need a little more traction to get that stripped screw head out or sometimes can be used on a closed end wrench and slightly rounded off bolt head. I've used the largest cobalt drill bit (that almost just covers the top rim of the nut) drilled through the nut--parallel to the bolt, then used a chisel to turn/peel the nut off of the bolt. ==References== *[http://www.hotrodders.com/forum/tip-day-33-a-75849.html Tip of the day #33], ''Hotrodders Bulletin Board'', December 10, 2005. *[http://en.wikipedia.org/wiki/Penetrating_oil Penetrating oil], ''Wikipedia'', retrieved July 15, 2006. *[http://www.chevytrucks.org/tech/stuckbolt.htm Stuck Bolts], ''ChevyTrucks.org'', retrieved July 16, 2006. *[http://www.pumaracing.co.uk/tooluse.htm Removing Stuck Fasteners] ''PumaRacing.co.uk'', retrieved July 16, 2006. *[http://www.rd.com/content/openContent.do?contentId=17889 Loosening Stubborn Nuts, Bolts, and Screws] ''Reader's Digest'', retrieved July 21, 2006. [[Category:Fasteners]] {{youcanedit}}

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