AweMan
Jedi Knight
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Stuck, Rusted Fastner {Bolt/Nut} removal
Hi my name is Kerry I have been a welder for many yesars, In the course of those years I have removed many stuck/rusted fastners from various items from castings to sheetmetal. During the course of browsing this forum I have seen many articles on how to`s for removing stuck/rusted bolts and nuts.
The first thing I will say is try a good quality penetrating oil let it stand for a while so it can do it`s job then try to remove the fastner. If possible and accessable use a wire brush to clean the threads that are protruding out of the nut on the bolt to be removed.
If this method fails:
A sharp blow with a hammer and punch will sometimes loosen up any rust/corrosion preventing the nut or bolt from turning. Use you own judgement on how hard you can strike the affected fastner without damaging the surrounding area on bolts you want to strike them directly on the head, a flat blow is essential. With nuts strike them on the flats all sides if possible again wirebrush any protruding threads you can access first and foremost.
If this method fails:
Here I will discuss the use of heat
Shetmetal is mild steel and using heat is not an issue on mild steel where structural integrety is an issue although you must keep in mind that distortion is. So keeping the heat on the fastner and trying to minimise heating the surrounding area is essential. An oxy/accetylene set is the best heat source for this purpose, use as small a tip as possible A 000 { Triple ought} is ideal for small fastners up to half inch heat the bolt/nut to cherry red do not liqufy them. Let the fastner cool to dark {No red} then try to remove them while still hot. You may need to make several attempte reheating the fastner each time. Remember the fastner is hot and its structural integrety is not the same as it was cold it is softer therefore it can twist of easily. It should come out fairly easy.
A word about castings {cast Iron} and heat. You can use heat to remove stuck fastners from castings but it is ESSENTIAL that you do not overheat the casting itself, this can cause it to crack and become useless until repaired by a professional welder. Once you are done working the stuck fastner out of a casting you need to prevent the casting from cooling too rapidly. a sandbox works well {cover the casting in dry warm sand} or even wraping it in a blanket but by no means let cold air blow directly on it.
Cast aluminum:
Not particularly supseptible to cracking because of heat but will begin melting before you very eyes if you are not very careful. A temp guage/stick is essential. Aluminum becomes liquid at around 1,800 degrees {you will never see red as you heat aluminum} there fore 400 to 900 degrees is a good area to maintain when working a stuck fastner out of aluminum castings even though you get the fastner out there is a very good chance that the threads in the casting will be destroyed {Just the nature of the beast} electrolisis and corrosion bond the steel to the aluminum and this bond usually destroys the threads. Threads on cast aluminum can be repaired using the helicoil method or the area can be welded in solid and re drilled and re taped. as long as the casting itself isn`t distorted from excessive heat.
Heat and hardened surfaces:
Parts like crankshafts, camshafts, rocker arms, flywheels, pressure plates or any part that is made out of a hardened material should under no circumstances be heated to more that 250 to 300 degrees if these parts are heated to the point that you can see a scale {carbon} precipitating out of the metal then the structural integrity is compromised. A hardened part in this condition is rendered useless. Again you can use heat to remove a stuck fastner but remember that you need to minimise the heat affected area {the surrounding area of said fastner} use a small tip maintain the heat on the fastner bring it to cherry red a wet rag can be used on the surrounding area to try to control the heat affected zone. let it cool so there is no red showing then try the removal. Remember heat the blot/nut not the part of course some residual heat will precipitate into the part but not enough to render it useless if you are careful.
Heat can not destroy the integrity of mild steel. Unless you of course melt it or distort it to the point of destruction. Heat can not destroy the integrity of aluminum. Unless you of course melt it or distort it to the point of destruction. Heat CAN AND WILL destroy the integrity of hardened steel if you heat it to the point it precipitates it`s carbon content. The carbon content is what makes hardened steel hard.
Good luck on fastner removal
P.S. chances are that if your car has sat for thirty years {or even less} in the elements then you will be resolved to using heat to remove the fastners, at least most of them
Remember: it is always a good idea to clean up any threads after you have removed the fastner before instaling a new fastner, this can be acomplished by using a thread chaser of the correct size and thread type or even a tap will work but you have to be careful using a tap not to start it cross threaded.
I hope this article at least helps someone.
Kerry
Hi my name is Kerry I have been a welder for many yesars, In the course of those years I have removed many stuck/rusted fastners from various items from castings to sheetmetal. During the course of browsing this forum I have seen many articles on how to`s for removing stuck/rusted bolts and nuts.
The first thing I will say is try a good quality penetrating oil let it stand for a while so it can do it`s job then try to remove the fastner. If possible and accessable use a wire brush to clean the threads that are protruding out of the nut on the bolt to be removed.
If this method fails:
A sharp blow with a hammer and punch will sometimes loosen up any rust/corrosion preventing the nut or bolt from turning. Use you own judgement on how hard you can strike the affected fastner without damaging the surrounding area on bolts you want to strike them directly on the head, a flat blow is essential. With nuts strike them on the flats all sides if possible again wirebrush any protruding threads you can access first and foremost.
If this method fails:
Here I will discuss the use of heat
Shetmetal is mild steel and using heat is not an issue on mild steel where structural integrety is an issue although you must keep in mind that distortion is. So keeping the heat on the fastner and trying to minimise heating the surrounding area is essential. An oxy/accetylene set is the best heat source for this purpose, use as small a tip as possible A 000 { Triple ought} is ideal for small fastners up to half inch heat the bolt/nut to cherry red do not liqufy them. Let the fastner cool to dark {No red} then try to remove them while still hot. You may need to make several attempte reheating the fastner each time. Remember the fastner is hot and its structural integrety is not the same as it was cold it is softer therefore it can twist of easily. It should come out fairly easy.
A word about castings {cast Iron} and heat. You can use heat to remove stuck fastners from castings but it is ESSENTIAL that you do not overheat the casting itself, this can cause it to crack and become useless until repaired by a professional welder. Once you are done working the stuck fastner out of a casting you need to prevent the casting from cooling too rapidly. a sandbox works well {cover the casting in dry warm sand} or even wraping it in a blanket but by no means let cold air blow directly on it.
Cast aluminum:
Not particularly supseptible to cracking because of heat but will begin melting before you very eyes if you are not very careful. A temp guage/stick is essential. Aluminum becomes liquid at around 1,800 degrees {you will never see red as you heat aluminum} there fore 400 to 900 degrees is a good area to maintain when working a stuck fastner out of aluminum castings even though you get the fastner out there is a very good chance that the threads in the casting will be destroyed {Just the nature of the beast} electrolisis and corrosion bond the steel to the aluminum and this bond usually destroys the threads. Threads on cast aluminum can be repaired using the helicoil method or the area can be welded in solid and re drilled and re taped. as long as the casting itself isn`t distorted from excessive heat.
Heat and hardened surfaces:
Parts like crankshafts, camshafts, rocker arms, flywheels, pressure plates or any part that is made out of a hardened material should under no circumstances be heated to more that 250 to 300 degrees if these parts are heated to the point that you can see a scale {carbon} precipitating out of the metal then the structural integrity is compromised. A hardened part in this condition is rendered useless. Again you can use heat to remove a stuck fastner but remember that you need to minimise the heat affected area {the surrounding area of said fastner} use a small tip maintain the heat on the fastner bring it to cherry red a wet rag can be used on the surrounding area to try to control the heat affected zone. let it cool so there is no red showing then try the removal. Remember heat the blot/nut not the part of course some residual heat will precipitate into the part but not enough to render it useless if you are careful.
Heat can not destroy the integrity of mild steel. Unless you of course melt it or distort it to the point of destruction. Heat can not destroy the integrity of aluminum. Unless you of course melt it or distort it to the point of destruction. Heat CAN AND WILL destroy the integrity of hardened steel if you heat it to the point it precipitates it`s carbon content. The carbon content is what makes hardened steel hard.
Good luck on fastner removal
P.S. chances are that if your car has sat for thirty years {or even less} in the elements then you will be resolved to using heat to remove the fastners, at least most of them
Remember: it is always a good idea to clean up any threads after you have removed the fastner before instaling a new fastner, this can be acomplished by using a thread chaser of the correct size and thread type or even a tap will work but you have to be careful using a tap not to start it cross threaded.
I hope this article at least helps someone.
Kerry