Nice vid. Just want to point out that WD-40 is not a good product to use for general lubrication. It's mainly a mix of alcohol, alkanes (water-repellent), and a VERY light mineral oil. It's so light, that's what makes it a good penetrating oil for unsticking a rusted in bolt or for any part that's gunked up. But any lubrication you do get (very little) will disappear in a short time. I've seen people make things worse by using WD-40 as a lubricant. The WD-40 will even clean out any existing oil. Then evaporate leaving virtually no protection. Instead, just use a general-purpose lubricating oil (like 3-in-1 oil). This will provide a better, and longer lasting lubrication. Depending on the use, a synthetic lubricant with teflon, or white lithium grease can also be used.
As an electrical engineer by training (a million years ago now) I had to take elective classes in other disciplines before graduating..I took a Chemistry class and then a Microscale Organic Chemistry class. I loved it so much that I had that feeling that I might have chosen the wrong field of study. Enjoyed your videos..just subscribed!
I worked in a trombone factory where there was an open 55 gal drum of /hydrochloric acid that wasn't vented. For years there I tasted metal in my mouth, til I figured out that the silver and gold was creating electrolysis aided by the acid in the air. I micro meshed my fillings and the metal taste was gone temporarily. I had them vent the acid pit and problem solved.
At last a video which gets to the basics. I'm getting tired of the debates about white vinegar vs. apple cider vinegar, etc. If one is using a simple acid to get rid of rust, it makes little difference which acid one uses. The difference is concentration and time. Even Coca-Cola is just a dilute acid (and a bunch of sugar). I appreciate your thoughtful approach to the problem. Thank you.
The problem with using acids is that the acid attacks the base metal and greatly weakens it, especially iron and steel. I left some steel parts in an acid bath for a bit too long and when I removed them, I could cut through the steel with a screw driver! The best rust removal method I have found that is non-destructive is electrolysis. It's fairly quick, acid free, and doesn't damage the parts.
Love doing this to older car parts then a bit of diy electroplating. For people who say "why not just buy new parts?", yes you can buy new fasteners etc, but on older cars alot of parts are obsolete nowadays. There something awesome about removing rust then plating the part
You should use a corrosion inhibitior in that solution, because it etches that bolts. And boil bolts in distilled water to remove remaining chlorides, wich is causing futher corrosion.
+Frank Beaulieu I kept only some of them, new ones are relatively cheap and the video was for demonstration. Ultimately I put some antiseize on them only since these bolts rust less than the Jeep frame anyway, which is being fixed now. Thanks for comment.
Is there any solution to neutralize the acid?Or put the bolt to the mixture of natrium bicarbonate first after that put to the water .Is it effective to fully neutralize the acid to prevent rust grow again?
+Just For Fun yes you can do as you say, neutralize first and then dip water. The chloric ions from the acid have to be eliminated. One way is to use a torch, heat until red and dip cool in oil. Thanks for comment!
It’s the same acid, only labelled by trade name as muriatic acid. Normally technical grade, meaning guaranteed 70 % purity, whereas I used 99 % but that doesn’t matter, the strength is the same. Thanks for bringing this up!
You have to be there and watch it. Depends on the nature of the rust. Can go fast or slow. As soon as everything is gone, then stop the process. Thanks for input, and good luck w your project!
Thanks for sharing! I guess the proportion by which this compound is dissolving the rust resp. the iron is constant and that the mixture ratio 1:1 in principle is arbitrary: Please correct me if I'm wrong. Also if I may ask, isn't there compounds that more selectively dissolves the rust and not the iron, or is hydrocloric acid the best in this regard?
The ratio was arbitrary, but taken concentrated enough to get a fast result. Hydro chloric acid is best in this regard unless you go mixed and more complicated acids. It is however not dissolving at the same rate, the rust (iron oxide) dissolves much faster because it is porous and the acid have easier access. Good point! Regards!
Mr Muscle in the grocery store or similar sewage drain cleaner works equally well. I used chemical grade NaOH but it doesn’t make a difference. Thx for comment!
So what is the best way to neutralize phosphoric acid on a car to then prime and paint? Alot of talk about this and I rewet with acid, let sit for 5 minutes, wash with water and a scotch Brite pad and dry with air or heat or both as fast as I can then use primer, paint etc. Is there a guaranteed way to show ppl to not be afraid of acids if used properly? Thank you. Very good video. Learned more her and in comments then most at all
Thank you for your comment. I think that in your case, in the particular case of phosphoric acid, the neutralization is not a big problem and only rinsing with water will take you far. The reason is that the process of rusting is related to the ability of the iron atoms with their acidic nature to interact with the water and the oxygen to form first hydrolyzed iron atoms that then quickly is converted into iron oxide, which is what is referred to as rust. The use of phosphoric acid as a rust remover is based on the benefits that the iron atoms prefer to strongly bond with the negative phosphorus atoms instead of hydrolyzing and oxidizing, which is a result of fundamental chemistry and acid basis theories related to the formation of certain solid precipitate before others (descriptive inorganic chemistry, I recommend reading Wulfberg). Having said this, I think that you are in a quite good position just to paint on the iron phosphate surface that you have after treating the surface with phosphoric acid and the bonding with any epoxy or thermoset paint should be excellent. If you instead use a thermoplastic paint, like most spray paints, then you could benefit from using a rust converter that contains both phosphoric acid and tannic acid. The tannic acid provides a more paint compatible surface since it is some hydrocarbon structures in the tannic acid resulting surface. A final comment, you still have an issue of not knowing how much you have converted your surface into iron phosphate because it is a surface reaction so always try to brush off as much as possible of the rust first. You can actually check your phosphors iron converted surface with a victorinox knife, scratch it and you will see if rust comes out under the black coat that you have formed. Good luck!
I cleaned a PC board from salt residues in isopropyl alcohol, pure, by completely immersing it for awhile. Then air dry. No water. Best look it up. Good luck
Going hotter would work for a while, about 10 degrees up, but even higher would make the hydrochloric acid evaporate away from the solutions. Thanks for y input!
I feel like this is half the process, yes Hydrochloric acid aka Muriatic acid is an excellent way of removing rust, but it is also an excellent way to accelerate the rusting process, I would have used baking soda water to neutralize it or better yet some high strength industrial grade vinegar to wash it off and coat it to prevent aka inhibit future rust from forming, I am curious how your bolts looked just a year later, not being rude, I just played this game before and had things super cleaned zero rust, and then the rust came back as quickly as it left
I have one of the nails in my other video running now since 2 days ago,in the acid, and dissolving the metal is very very slow - at least 100 times slower. I will check it and get back with a better estimate.
Anyone ever heard of Hydrogen Embrittlement.? Automotive and aerospace fasteners should never be immersed in acid,or as I keep seeing on these “home made” videos subjected to electrolysis cleaning methods. The parts will absorb hydrogen during these procedures and become brittle as a result of hydrogen absorption. The only way to remove the hydrogen is to bake the parts at least 200 degrees for at least four hours, depending on the immersions time and the grade of the steel. I don’t know what these bolts are for but if they are safety critical parts ie for brake callipers, wheel nuts, or steering racks etc, they could fail under load or pressure. I have just retired 12 months ago from 48 years of management in the metal finishing industry,( paint, powder coat, EP paint and electroplating)of high grade high spec aerospace and automotive parts and fasteners. The specifications of these parts do not allow them to be subjected to any chemical processes, and in the rare occasion that they are, they have to undertake a baking process of at least 8/12 hrs at 200 degrees to remove the hydrogen. Such high spec parts are usually “ mechanically cleaned”, ie hot soapy non alkaline cleaning and peening or shot blasted to prepare the surface for the subsequent coating. Sick of seeing these do it yourself electroplating and electrolysis cleaning videos. If it’s a old bolt for the gate or a couple old door handles that’s fine but DO NOT process safety critical parts using these videos.!!
Why are there so many videos about electroplating without one mentionning Hydrogen Embrittlement ? Are 99% of the youtubers uneducated ? Also all the web articles wrong ? Why is there 0 emphasis put on this embrittlement ? What do you recommend then to rejuvenate corroded fasteners.
Quiet man that's fascinating information you provided ! Thank you for your service in the metal finishing industry. How would you suggest the average person remove rust from metal? Chemical , media blast , electrolysis ? What method removes the rust effectively in a timely manner but does little to take good metal with it. Please give details.
Mainly high tensile steel (>1000 MPa) is affected by this (according to wikipedia). So for high tensile strength bolts, yes. But much less of a problem for many other steel parts I suppose.
Hey quiet man a question, After alot of arguments about Ospho or phosphoric acid used on automobiles to address rust, what's the best way to neutralize acid for using a epoxy, urethane type primer or paint? I know I can clean with mineral spirits and use rustoleum, but what if using the above mentioned? Thank you so much.
only a chemist would make a major production out of something so simple, forget the glass beaker and water, just grab a plastic container throw the bolts in and pour in enough straight muriatic acid in to cover the bolts, they should be rust free in less then an hour. then take the bolts out, rinse with fresh water, blow them dry with a compressor is preferred but if you don't have a compressor then dry with a towel and spray with wd40 so the don't flash rust again. with the amount of rust on the bolts in this video, the whole job could be done in an hour at the most but if you want it even faster and have an old aquarium air pump throw a airline in the acid to act as a bubblier and it should knock about a 1/3 of the time off . but something i didn't hear him mention, do the job outside, especially if you use a bubblier so you don't breath the fumes or rust all the metal objects in the immediate area....
Quadflopper101 Muriatic acid is hydrochloric acid. Vinegar is acetic acid. Lemon juice is citric acid. Don’t knock the chemists; they know more than you do. And they can spell!
+Wayne Allsopp Thanks for asking. Hydrogen embrittlement is a process where hydrogen dissolves and diffuse into the metal. The diffusion of the hydrogen is different from material to material, and the scientific view is that it is a reversible process, meaning that the hydrogen can also leave the metal. You may read in the comments and statements claiming horrible effects and the fact that the material to some extent looses ductility (toughness). In reality one has to do mechanical testing to verify hydrogen embrittlement for these specific bolts and with their specific material grade. Since we also see some serious pitting where the rust was sitting, which certainly has reduced the thickness of the bolt, this would be my main concern if we talk material strength. However, would I worry about these bolts? Well, these are not wheel lug nuts and they are in reality used to hold up a transmission as 6 aligned bolts. I would be surprised if all of them snapped at exactly the same second so I drop my transmission. For anyone worried, I would say `buy new’. Neither would I recommend this person to drive a Wrangler without airbags. I hope this helps and thanks again for asking!
+Robert Ferguson it takes days for the hydrogen to penetrate deep into the steel according to all scientific reports i have been able to find. Not 30 minutes. The strength has primarily been reduced from the lost iron that went into rust. Thx good point comment!
Question. If there is still rust areas and say a paint/ clear coat is applied for rust prevention. Does the already rusted areas that were not removed continue to penetrate the metals' integrity, or does the the paint (rust specified paint) fully keep deep rust from damaging the metal?
Rust forms as a consequence of iron interaction with water. Now, if you paint or clear coat your part so absolutely 0.00% water gets in under the coating, the remaining rust won't do much in converting iron into rust (iron oxide). The problem is that such paint or clear coat does not exist. All paints and clear coats are letting through a little bit of water with time, and it is referred to as 'permeability of plastics'. The 'permeability of plastics' explain why you sometimes get your medicine in aluminum sheets. That is because the drugs are very sensitive to water (humidity), and the suppliers want to be sure that no water gets through during the shelf-life of the drugs. Aluminum is completely impermeable. What folks do in the car business is thus to use the best possible option, since they cannot seal their cars with aluminum. They remove as much rust as possible because the rust in itself attracts more water than pure iron does, then they use paint (rust specified paint) that contains zinc because the zinc reacts with water before the water reacts with the iron (as a sacrifice metal). Some companies claim that they have the coating/paint that is completely sealing out the water so they don't need the zinc in the paint, but that is not true since no such paint/coatings exist. However, there are better and worse coatings towards sealing out the water. So, basically the answer is that no painting/coating will forever seal your iron against water but with a good coating you will make new rust formation happen much slower. If you also have the zinc in there, it will take even more time for the conversion of iron into rust to happen, but even in this case there is a day when the zinc has been consumed and water will be there again. Thanks for good input!
when it comes to cleaning you have level one ,level two or level three .. etc .. oxygen and moisture must be present to create rust. paint will stop both from getting to the metal but when the paint gets old and fails then rust starts . rust will destroy a metal and it will take some time .. how long has to do with moisture ,salt, oxygen ..no Mather it takes a long time for metal to fail in most application ..for a bolt to fail in a car you have approx. 10 years or more .you can use anode to slow the rust problem .
+Albert Thane I left a railway nail from my other videos in there for 2 weeks, believing it would eventually complete dissolve, since some comments on this video state concerns on hydrogen embrittlement and migration of the acid into the bolts. In reality what happens is that the surface is passivated by a black ferrihydrate layer and then the rust removal reaction stops. I cut the nail up and it was perfectly shiny solid steel after a week. I would not use more than necessary I was to trust the bolts as it high strength bolts.
Hello, Regarding the "PH" in the PH scale does that stand for "presence of hydrogen" as I have recently been told? Good topic in your video. I am always interested in fighting rust. Take care. Doug
Douglas Thompson sorry Doug, I missed your comment. The answer is that it basically means how much hydrogen atoms you have as hydrogen ions in your solution. However the p doesn’t stand for ‘presence’ of the hydrogen in the solution. The problem is that the concentrations range over so big numbers, from very small to extremely large numbers, so someone had to figure out how to get it on a scale from 1 acidic to 14 alkaline, without 50 millions of digits after a comma. And to be correct the p stands for the negative logarithm of the H (concentration of hydrogen).
Fasteners, unless made of exotic materials are not expensive and using old fasteners cleaned up with acid is not a good idea for several reasons; firstly the clamping surfaces are damaged and will not provide even pressures, secondly the threads will be rough and will, especially if being screwed into a soft material such as aluminium, damage the female thread and thirdly the torque applied to the fasteners will be incorrect (due to the first two points), especially if the overall diameter of the faster has been reduced. For wheel bolts, it might not make much of a difference assuming the hub is also steel or iron,, but for any application that requires a specific torque and/or is being used in a soft material, it's better in the long run to use new fasteners. Nice little video though.
Good advice. To that I'll add that in dynamic application where there is load cycling, the potential of FATIGUE FAILURE increases with the length of in-service life of the fastener/material. All structural materials have a 'fatigue endurance limit' for use in cyclical load applications - for most common steels, typically at 30% of ultimate tensile strength PLUS about 1 million load cycles above or near that 'endurance limit'. Exceed that endurance limit and most assuredly the part/component/fastener WILL fail, and catastrophically without warning. Fatigue happens along the macro 'grain boundaries' of the metal, weakens the material ..... and in corrosive service (consider wintertime road salt), allows chemicals, salts, etc. to enter INTO and along the metal grain boundaries which then propagate internal corrosion of the metal for 'further' weakening. Imagine if your bolt has begun to develop micro-fatigue cracks and you then 'soak' them in muriatic/hydrochloric acid and that acid has penetrated into the base metal via these microscopic CRACKS. For critical structure and their 'fasteners' in cyclic load bearing service, the best course is to ALWAYS replace the fasteners with NEW (to the exact same LOAD rating). That way your control arms, steering links, your 'hard' brake lines, your calipers, your engine/transmission mounting bolts, your 'universal joint' bolts, etc. etc. won't fall apart/off at the least expected timing. If you really want to clean the rust from a bolt or stud (or steel tool), etc. there's a much better and simpler way: Firstly a brief clean-up with a rotating wire wheel to remove the 'loose stuff'. Followed by - *BOILING the part in plain WATER* for a half an hour or more (the longer 'the boil', the better). What will happen is the remaining RED (ferric) rust will begin to convert to BLACK (ferrous) rust. RED rust is destructive; BLACK rust is 'protective' - similar to the 'blueing' finish on firearms. Lastly & after assembly, spritz on some *BOESHIELD T9* which is a wax-like metal protectant ... used extensively on aircraft and other 'critical' maintenance venues. Hope this helps. www.amazon.com/BOESHIELD-Corrosion-Protection-Waterproof-Lubrication/dp/B001447PEK/ref=sr_1_1?ie=UTF8&qid=1522078033&sr=8-1&keywords=boeshield+t9&dpID=417rK6tOOoL&preST=_SY300_QL70_&dpSrc=srch
Great point, as clamping force is the main point of fasteners. I've seen many machinists use Evaporust to remove rust without impacting the structure of the part being treated. They even use it on parts that are precision ground/scraped.
So have I, but I'm pretty choosy about which to use again and which to discard - I wouldn't use de-rusted or reclaimed cylinder head suds or bolts, for example.
It has crossed my mind that a paste with acidic components/chemicals inside would have been a nice thing to paint on and then blow it off with water. Possibly there are already something like that, and maybe that is what they put into rust converters. They are called rust converters but surely there is noting in rust converters that brings back the original iron, its a scientific impossibility. The only thing that brings back the iron is electrochemical processes that would do the reverse to what you see in the video, but then the problem is that the iron formed is not as strong as the original iron because it becomes porous. Myself I stick with this, and if it's too corroded resulting in too much pitting showing after acid elimination, then I only replace the part. On a panel you could just paint on the acid solution and let it sit if its flat but be careful with the acid and make sure you neutralize the surface after. The surface you get is perfectly fine to prime and then paint. Good luck and thanks for your comment.
Great video. Do anyone know if I have to neutralize OSPHO ( phosphoric acid) after using it on the car chassis before I paint? not concern about paint adhesion but acid eating away the metal longterm.
The part that adds to corrosion in the long run, from reminding acid, is relate to the counter ion. If you would have sulphuric acid, then it’s the sulphate group, if you have hydrochloric acid then it’s the chloride group. In this case of phosphoric acid, then the phosphorus group is bonded into the new surface so rinsing is in most cases good enough and the phosphorus group as bonded into iron phosphate is not catalyzing more rust
100% is only existing as gas. The highest concentration existing in liquid form is 37%, rest is water. Boiling this 37% liquid will release 100% hydro chloric acid as gas, but it will immediately be diluted with air. I took the 37 and doubled the volumer with water so what you see is a 18.5 % solution. The reason i did this was because the 37% fume of so much corrosive acidic gas that it would blur the lens.
Thank you very much for the info I have my late fathers auto tools that has some rust on them I was told to use distilled Vinegar and water but your way looks like a faster way again thank you.
Wouldn't a dip of these bolts in used motor oil do the same thing to prevent rusting in the future? Makes sense to me, I am not confident of WD40 to be honest.
I'm restoring a couple of cars and have a lot of rusty bolts and small parts etc. The carburettor cleaned up like new by soaking overnight with vinegar but vinegar was only so-so with bolts. Citrus acid works well with cleaning bolts but I was busted by my wife boiling bolts in citrus acid in her best pots. Today I've tried Hydrochloric acid and it is by far the best. Cheap to buy and sorted bolts in about an hour of soaking for 10min then wire brushing then soaking again. Only issue is the grease/oil that ends up covering every items and reduces the effectiveness of the acid. Has anyone got a solution for removing oil?
For steel and iron, you can do a mix of 40 grams caustic soda + 25 grams of sodium carbonate + some detergent (all per litre) and then heat it so it simmers. Let them sit in there for 10-15 min. This is basically the toilet cleaner + washing powder + liquid hand washing detergent. However, be aware and definitely use eye protection. Lots of folks believe acids in the eyes is the worst. That’s not true, alkaline (like the above) are the worst. If you splash this - your vision will be instantaneously, irreversibly and permanently blurred. You cannot use it on aluminum or zinc, it will erode your metal. If you want to go solvents, the stoddard solvents are the strongest but road tar is often too tough sitting, and I have had limited success. In the old times they used chlorinated stuff in there, which is banned today. This stuff is still used in some paint dissolvers but it is very nasty - it’s carcinogenic. For solvent based I recommend normal petrol (gasoline). I am always surprised how well it dissolves stuff and I have no clue what they put in there. Good luck.
I think if you're working on the body of the car phosphoric acid is better to use. Safer to use and it has a thicker consistency so it's easier to brush on.
Isn't Muriatic Acid (used for masonry cleaning, etc.) the same acid? Its available in most hardware stores and home centers in the US. Perhaps its already diluted?
A 37% hydrochloric acid makes fumes like smoke when u open the bottle. 28-30 from paint stores don’t produce theses fumes at room temperature. A 30 % would need 1 cup of water per 3 cups of acid to reach same condition as in this video.
These fasteners need something for the oil to stick to or they will rust again in a year or less. Gun blue works pretty good, or simply let them flash rust and boil them for a black oxide then oil them.
Lay them on thier side for less wasted volume as you cover them in liquid. Forget the water, just use hardware store Muriatic acid. been doing it for years.
I believe adding hexamine to the hydrochloric acid will stop/reduce the rate of acid attack on the bare steel. We used to use this solution when cleaning hardened concrete off of the steel concrete mixers in the Concrete Laboratory when the students hadn't bothered. That is a lot of concrete in one sentence! Apparently the hexamine attaches to the bare iron but not the iron oxide.
It just seems easier to hit the metal with a wire wheel then spray it with RP-342 "HEAVY" Military-Grade Rust Preventive Aerosol Spray. Rather than a 2hr wait they'll be ready in 10 minutes. Just saying.
@@chinchillaintheheat2641 exactly, and if you try to remove that nut off the bolt to replace it without removing the rust from the bolt.. you will break it. Unfortunately some of these bolts like a rear fascia mounting bolt are welded to the frame, you "really" can not afford to snap that bolt and break it. You have to deal with the rust or you will break it.
Are there any I'll effects of using this method to derust a car frame and the suspension? I plan on building a tank to soak the parts an am torn between citric acid, vinegar and the hyrochoric acid. Let me know what you think. Thanks.
In principle, all the rust you remove has no strength at all in itself. If you would go to the shop and buy rust dissolver you would likely get something based on phosphorus acid. The reason is that chloride, as in hydro chloric acid, can bond and stay with the metal (iron) and its corrosive there as well, that is if you expose the parts you have cleaned to water, i.e. in the future. Nothing beats hydrocholoric acid in efficiency though, and if you have used it you should make sure that you treat the part in an alkaline bath as well, to neutralize the chloric acid. I have no issue with using most of the above bolts again, because if you think about it, I have only removed useless surface rust. On one bolt in the video, you can see that the neck has rusted away extensively. This bolt was thrown away. There is no good reason to compromise safety. Good luck! PS. If you chose any of the other acids you mention, a bit of heat will speed up your progress.
I have used phosphoric acid to clean an old gas tank and it came out like new! I dropped nuts & bolts and a few feet of an old tow chain in there and me and my neighbor shook it like hell to agitate it. Got the acid at home depot in the garden section. ✌
Better to boil them in vinegar, as HCl penetrates the structure of the bolts and weakens them. Acetic acid attacks the rust, but doesn't damage the metal of the bolts so much.
Will it affect the integrity of the metal or Strength of the metal? Can I have it 1:8 (1 part HCL 8 parts water) and leave it for 24 hours without the solution eating away my metal?
It is much much more difficult to dissolve the iron in itself than the rust because the rust is porous if you would look at it in a microscope. However, since HCl is very active I would not just dump it in there and leave it. Based on the results I had on 50:50 you are 1/4 in concentration so possibly you would have the same result in 6-8 hours but it is also dependent on the nature of your rust. If it is very porous rust it will go faster. I would try and see what happens after 3 hours, the eating of the metal is very slow and the reactions slowed down at the end when most of it was dissolved. It's however always important to neutralize your metal object surfaces after the rust removal by using some sodium hydroxide of similar alkaline chemical. Cheers and thanks for the comment!
Hi Ken, Thanks for a very informative video and response. Unfortunately, I have to work blind on this one,as I have placed the solution inside an old air compressor tank which had rusted away for years of use. The tank has only small holes 1/2" and 3/4" inches on it, hence, can't really see what's going on inside. With this I can only hope and guess perhaps that it has done it's job inside there. I have tried to pick a borescope / endoscope whatever it's called on ebay, but it will be weeks from now until it arrives. I've place the solution (1:8) yesterday evening, hence, it'll be 24hours when I get back tonight. I hope it hadn't really eaten through the metal now as hours had passed. (crossing fingers). The muriatic acid by the way in it's label says (15% HCL, 85% Aqueous vehicle), Aqueous Vehicle probably is water?. This is why I'm asking if it had ruined the integrity of the metal as I have left it longer than your experiment, although mine was (1:8) solution as to your 1:1. and yes, I have prepared baking soda, and will dissolve it in water upon flushing out the HCL solution. After the soda solution, I'm planning to flush again a rust converter inside, basically, shaking the tank so the rust converter covers the inside surface area of the tank. Maybe top it again with red lead after the rust converter dries.
I have always been curious what the "rust converters" are. I noticed that an additive to most of these is poly ethylene glycol but I have read that it is also an acid. What is the best way to coat iron after being treated besides priming? I remember reading some old 1800's artillery books and they described a process used to coat cannons on ships, so you know it had to work being near salt water all the time.
The best way to treat iron if you wish to prevent rust is to look at how experts are treating iron in historical monuments. They use something called in Swedish 'blymönja', which resembles something like a 'lead paste with tar similar properties'. This sort of rust prevention is banned in many European countries for private citizens to use because it contains lead oxide but allowed for historical restorations. Lead oxide was dominantly mined in Spain in the 18 century and I would not be surprised if this was used in some cannons or ships coatings .
Rust converters are based on tannic acid, from tree sap, a very particular acid, in the old times they used this acid as in wood shaves to put togehter with the tools in the toolboxes, to prevent rusting. However, tannic acid is a weak acids, and therefore they complement with phosphoric acid to speed up the conversion in rust converters. Here i show phosphorous acid as compared to the above: ruclips.net/user/edit?o=U&video_id=5Bkdej_z1HI
Crossed my mind but after pooking a bit in the rust, as I did the acid comparison in the other video, it seamed the process is both fragmentation and dissolution so it basically falls off and dissolves at the same time. The dissolving is the stuff that takes time, the acid needs to work it’s way into the pores of the rust, so I am not sure the shaking or agitation would do much. Agitating with some acid resistant sand, ...?? but then there’s the issue w the messy acid. For other parts I do, a small temp increase of conc increase is more effective in speedin it up
Why not phosphoric acid? I usualy use a product with 25-30% phosphoric acid and the rest is simply surfactants and soap, just in case you want to scrub it off instead of waiting for hours.
Rust is a mix of FeO and Fe2O3, along with bound water. Phosphoric acid will react with the rust and form Fe3(PO4)2 and FePO4, both of which are insoluble, so will coat the iron and NOT color the solution. In effect, the rust will be transformed and just seem darker. In that video, it sounds like you were expecting it to dissolve the rust.
I believe you could use 'Muriatic Acid' from the paint or pool store, although it is less concentrated if I remember correctly. Nice work. Is this your hood at work or personal work space?
Indeed, you are right about the Muriatic acid. Muriatic acid is a less purified hydro chloric acid sold as 30% instead of chemically pure maximum concentration 37%. This difference has no relevance and Muriatic acid would do the same job, and in fact only mixing 1 part Muriatic with 2 parts water would practically work equally fast. This experiment was done in a professional lab hood, my personal, for using in my teaching activities at the university and it is very well ventilated. I would not do this inside my kitchen at home, but at the same time wouldn't hesitate doing it outside my garage if all precautions are made. After all, Muriatic acid is sold openly and there are much worse things out there. Improper handling of firecrackers or fuel from the petrol station, for example.
For lighter rust on smaller objects, sure, wire wheels are just fine. I'm confident it'd take more than 15 seconds a piece for anything with heavier rust.
I read in a different comment that these are crossmember bolts. Really strange, I've never seen these on a jeep YJ. They do look a lot like lug bolts like a lot of European cars have.
I still prefer electrolytic rust removal. It is easy to make your own setup. And you need nothing harsher than some water and bicarb and a car battery charger.
For all us non chemist mechanics out here: 1) what is the molar concentration of the acid solution? 2) what temperature did you conduct this redox reaction at? 3) what is the effect of substances on the metal substrate which are not soluble in polar solvents? 4) what are the consequences of the presence of chromium in the reaction? 5) är din Jeep Wrangler nu en EPO traktor?
Thanks Derek. Excellent input. 15. The temperature is room temperature. Paints, oils and silicone block the reactions. This is not stainless, and I am not sure why you ask about chromium. Always. Cheers!
Ken Sweden I was skojing a bit. About chromium, I know that toxic chrome salts are released during electrolysis and wondered if the same was true here.
What about a 50/50 concentration of Phosphoric Acid and Water? That is what I use and it works faster and better than HCL. I am also an organic chemist.
The metal looks kind of sandblasted as if the acid had reacted with the base metal. However, maybe they looked that way before you put them in the acid solution?
true, but the sandblasted appearance comes from the rust that has been dug into the surface and then was dissolved. materials scientists call in pitting.
After this process you should have run a blow torch over them to get rid of the acid. I would have rinsed in baking soda (strong base to neutralize the acid) and then heat treated to parts with a flame. This is actually how a chemist would do it.
Nice vid.
Just want to point out that WD-40 is not a good product to use for general lubrication. It's mainly a mix of alcohol, alkanes (water-repellent), and a VERY light mineral oil. It's so light, that's what makes it a good penetrating oil for unsticking a rusted in bolt or for any part that's gunked up. But any lubrication you do get (very little) will disappear in a short time.
I've seen people make things worse by using WD-40 as a lubricant. The WD-40 will even clean out any existing oil. Then evaporate leaving virtually no protection.
Instead, just use a general-purpose lubricating oil (like 3-in-1 oil). This will provide a better, and longer lasting lubrication. Depending on the use, a synthetic lubricant with teflon, or white lithium grease can also be used.
Very satisfying video to watch, calmed me down after a rough day at work and it pleases my OCD.
O yah that ocd a bitch sometimes when it Flyers up
As an electrical engineer by training (a million years ago now) I had to take elective classes in other disciplines before graduating..I took a Chemistry class and then a Microscale Organic Chemistry class. I loved it so much that I had that feeling that I might have chosen the wrong field of study. Enjoyed your videos..just subscribed!
Never too late! Unless ur dead.
Would it help if you put this in an ultrasonic cleaner?
Bench grinder w/wire wheel and pliers to hold the bolts?
I worked in a trombone factory where there was an open 55 gal drum of /hydrochloric acid that wasn't vented. For years there I tasted metal in my mouth, til I figured out that the silver and gold was creating electrolysis aided by the acid in the air. I micro meshed my fillings and the metal taste was gone temporarily. I had them vent the acid pit and problem solved.
At last a video which gets to the basics. I'm getting tired of the debates about white vinegar vs. apple cider vinegar, etc. If one is using a simple acid to get rid of rust, it makes little difference which acid one uses. The difference is concentration and time. Even Coca-Cola is just a dilute acid (and a bunch of sugar). I appreciate your thoughtful approach to the problem. Thank you.
here's the difference between the acids. thanks. ruclips.net/user/edit?o=U&video_id=5Bkdej_z1HI
will Coke Zero work? my bike's on a diet.....
The problem with using acids is that the acid attacks the base metal and greatly weakens it, especially iron and steel. I left some steel parts in an acid bath for a bit too long and when I removed them, I could cut through the steel with a screw driver! The best rust removal method I have found that is non-destructive is electrolysis. It's fairly quick, acid free, and doesn't damage the parts.
Nice detail. I'm 98% sure those are wheel bolts (not skidplate) from the conical seat.
Love doing this to older car parts then a bit of diy electroplating. For people who say "why not just buy new parts?", yes you can buy new fasteners etc, but on older cars alot of parts are obsolete nowadays. There something awesome about removing rust then plating the part
Thanks for your time in thoroughly explaining the process. What was your starting concentration of HCl before you added it to the water?
Somewhere 35-37%. The bottle had been standing for a while
New bolts are about $1 each. How much does acid cost?
Are they still in tollerances in terms of diameters?
Very tight, no problem, but I exchanged the bad ones.
You should use a corrosion inhibitior in that solution, because it etches that bolts.
And boil bolts in distilled water to remove remaining chlorides, wich is causing futher corrosion.
sprayed with WD-40 to protect the bolts, but do you paint the bolts head before ?
+Frank Beaulieu I kept only some of them, new ones are relatively cheap and the video was for demonstration. Ultimately I put some antiseize on them only since these bolts rust less than the Jeep frame anyway, which is being fixed now. Thanks for comment.
@@Ken_Sweden Cool thx man !
Is there any solution to neutralize the acid?Or put the bolt to the mixture of natrium bicarbonate first after that put to the water .Is it effective to fully neutralize the acid to prevent rust grow again?
+Just For Fun yes you can do as you say, neutralize first and then dip water. The chloric ions from the acid have to be eliminated. One way is to use a torch, heat until red and dip cool in oil. Thanks for comment!
Ken Sweden thx
I am curious, why hydrochloric instead of muriatic acid? I have used muriatic (because that is what I had) with excellent results. Thanks!
It’s the same acid, only labelled by trade name as muriatic acid. Normally technical grade, meaning guaranteed 70 % purity, whereas I used 99 % but that doesn’t matter, the strength is the same. Thanks for bringing this up!
Thanks. And now I know what muriatic acid really is.
Thank you 🙏 what concentration of hydrochloride acid did you use? 30%?
Yes! Of the 37%
Will the acid dissolve aluminium oxide as well? Thanks.
Replying to my own comment, no it won't dissolve aluminium oxide.
How many hours should i soak the rusted metal.
You have to be there and watch it. Depends on the nature of the rust. Can go fast or slow. As soon as everything is gone, then stop the process. Thanks for input, and good luck w your project!
Thanks for sharing! I guess the proportion by which this compound is dissolving the rust resp. the iron is constant and that the mixture ratio 1:1 in principle is arbitrary: Please correct me if I'm wrong. Also if I may ask, isn't there compounds that more selectively dissolves the rust and not the iron, or is hydrocloric acid the best in this regard?
The ratio was arbitrary, but taken concentrated enough to get a fast result. Hydro chloric acid is best in this regard unless you go mixed and more complicated acids. It is however not dissolving at the same rate, the rust (iron oxide) dissolves much faster because it is porous and the acid have easier access. Good point! Regards!
What alkaline solution did you use, and what easily available alkaline would you recommend we use?
Mr Muscle in the grocery store or similar sewage drain cleaner works equally well. I used chemical grade NaOH but it doesn’t make a difference. Thx for comment!
Thanks for the video. Is there a "special" strength of acid? Also, what is the handiest source for lay people to obtain it? Thanks.
Any paint store, as muriatic acid, which is the trade name. Thanks for watching!
He did it 50/ 50
Does it weaken the metal since its acid?
So what is the best way to neutralize phosphoric acid on a car to then prime and paint? Alot of talk about this and I rewet with acid, let sit for 5 minutes, wash with water and a scotch Brite pad and dry with air or heat or both as fast as I can then use primer, paint etc. Is there a guaranteed way to show ppl to not be afraid of acids if used properly? Thank you. Very good video. Learned more her and in comments then most at all
Thank you for your comment. I think that in your case, in the particular case of phosphoric acid, the neutralization is not a big problem and only rinsing with water will take you far. The reason is that the process of rusting is related to the ability of the iron atoms with their acidic nature to interact with the water and the oxygen to form first hydrolyzed iron atoms that then quickly is converted into iron oxide, which is what is referred to as rust. The use of phosphoric acid as a rust remover is based on the benefits that the iron atoms prefer to strongly bond with the negative phosphorus atoms instead of hydrolyzing and oxidizing, which is a result of fundamental chemistry and acid basis theories related to the formation of certain solid precipitate before others (descriptive inorganic chemistry, I recommend reading Wulfberg). Having said this, I think that you are in a quite good position just to paint on the iron phosphate surface that you have after treating the surface with phosphoric acid and the bonding with any epoxy or thermoset paint should be excellent. If you instead use a thermoplastic paint, like most spray paints, then you could benefit from using a rust converter that contains both phosphoric acid and tannic acid. The tannic acid provides a more paint compatible surface since it is some hydrocarbon structures in the tannic acid resulting surface. A final comment, you still have an issue of not knowing how much you have converted your surface into iron phosphate because it is a surface reaction so always try to brush off as much as possible of the rust first. You can actually check your phosphors iron converted surface with a victorinox knife, scratch it and you will see if rust comes out under the black coat that you have formed. Good luck!
What is the strength of the acid?
How do you dissolve salt residue from pc board?
I cleaned a PC board from salt residues in isopropyl alcohol, pure, by completely immersing it for awhile. Then air dry. No water. Best look it up. Good luck
Is it better to use distilled water?
No, it has No relevance
WD-40, displace water. Would isopropyl alcohol do the same ?
Isopropyl alcohol mixes very well with water, no displacement and it evaporates before the water so in the end it will be rust again. Thx f comment.
So probably a nice hot bath in used motor oil.
no ref to temperature would hotter work quicker?
Going hotter would work for a while, about 10 degrees up, but even higher would make the hydrochloric acid evaporate away from the solutions. Thanks for y input!
any acid or do some acids work better? What about Oxalic acid? I ask this with regards removing iron oxide from silicon dioxide.
so where does everyone dispose of all the rust removers i wonder????
I feel like this is half the process, yes Hydrochloric acid aka Muriatic acid is an excellent way of removing rust, but it is also an excellent way to accelerate the rusting process, I would have used baking soda water to neutralize it or better yet some high strength industrial grade vinegar to wash it off and coat it to prevent aka inhibit future rust from forming, I am curious how your bolts looked just a year later, not being rude, I just played this game before and had things super cleaned zero rust, and then the rust came back as quickly as it left
would circulating acid speed up the process?
Yes, and even more if you could do it in an ultrasound bath for cleaning jewelry.
Will the rust come back??
So far not. Best is to coat them with tannic acid. Or you heat them to 300 C and dip them in linseed oil
How long before the acid starts eating into the good metal?
I have one of the nails in my other video running now since 2 days ago,in the acid, and dissolving the metal is very very slow - at least 100 times slower. I will check it and get back with a better estimate.
Anyone ever heard of Hydrogen Embrittlement.?
Automotive and aerospace fasteners should never be immersed in acid,or as I keep seeing on these “home made” videos subjected to electrolysis cleaning methods. The parts will absorb hydrogen during these procedures and become brittle as a result of hydrogen absorption. The only way to remove the hydrogen is to bake the parts at least 200 degrees for at least four hours, depending on the immersions time and the grade of the steel. I don’t know what these bolts are for but if they are safety critical parts ie for brake callipers, wheel nuts, or steering racks etc, they could fail under load or pressure. I have just retired 12 months ago from 48 years of management in the metal finishing industry,( paint, powder coat, EP paint and electroplating)of high grade high spec aerospace and automotive parts and fasteners. The specifications of these parts do not allow them to be subjected to any chemical processes, and in the rare occasion that they are, they have to undertake a baking process of at least 8/12 hrs at 200 degrees to remove the hydrogen.
Such high spec parts are usually “ mechanically cleaned”, ie hot soapy non alkaline cleaning and peening or shot blasted to prepare the surface for the subsequent coating.
Sick of seeing these do it yourself electroplating and electrolysis cleaning videos. If it’s a old bolt for the gate or a couple old door handles that’s fine but DO NOT process safety critical parts using these videos.!!
Why are there so many videos about electroplating without one mentionning Hydrogen Embrittlement ? Are 99% of the youtubers uneducated ? Also all the web articles wrong ?
Why is there 0 emphasis put on this embrittlement ?
What do you recommend then to rejuvenate corroded fasteners.
Quiet man that's fascinating information you provided ! Thank you for your service in the metal finishing industry. How would you suggest the average person remove rust from metal? Chemical , media blast , electrolysis ? What method removes the rust effectively in a timely manner but does little to take good metal with it. Please give details.
Mainly high tensile steel (>1000 MPa) is affected by this (according to wikipedia). So for high tensile strength bolts, yes. But much less of a problem for many other steel parts I suppose.
@@zjeng1Which ones are high tensil bolts in a car ?
Hey quiet man a question, After alot of arguments about Ospho or phosphoric acid used on automobiles to address rust, what's the best way to neutralize acid for using a epoxy, urethane type primer or paint? I know I can clean with mineral spirits and use rustoleum, but what if using the above mentioned? Thank you so much.
only a chemist would make a major production out of something so simple, forget the glass beaker and water, just grab a plastic container throw the bolts in and pour in enough straight muriatic acid in to cover the bolts, they should be rust free in less then an hour. then take the bolts out, rinse with fresh water, blow them dry with a compressor is preferred but if you don't have a compressor then dry with a towel and spray with wd40 so the don't flash rust again. with the amount of rust on the bolts in this video, the whole job could be done in an hour at the most but if you want it even faster and have an old aquarium air pump throw a airline in the acid to act as a bubblier and it should knock about a 1/3 of the time off .
but something i didn't hear him mention, do the job outside, especially if you use a bubblier so you don't breath the fumes or rust all the metal objects in the immediate area....
Quadflopper101
Muriatic acid is hydrochloric acid.
Vinegar is acetic acid.
Lemon juice is citric acid.
Don’t knock the chemists; they know more than you do.
And they can spell!
could you use sulfuric acid?
+Rob Simpson yes but it is slower. Thanks for watching, I compare all acids in another video
That's how I prep all the parts I zinc plate, but I use strait acid and my part are usually clean in a few minutes.
Does this not cause hydrogen in-brittlment like electroplating
+Wayne Allsopp Thanks for asking. Hydrogen embrittlement is a process where hydrogen dissolves and diffuse into the metal. The diffusion of the hydrogen is different from material to material, and the scientific view is that it is a reversible process, meaning that the hydrogen can also leave the metal. You may read in the comments and statements claiming horrible effects and the fact that the material to some extent looses ductility (toughness). In reality one has to do mechanical testing to verify hydrogen embrittlement for these specific bolts and with their specific material grade. Since we also see some serious pitting where the rust was sitting, which certainly has reduced the thickness of the bolt, this would be my main concern if we talk material strength. However, would I worry about these bolts? Well, these are not wheel lug nuts and they are in reality used to hold up a transmission as 6 aligned bolts. I would be surprised if all of them snapped at exactly the same second so I drop my transmission. For anyone worried, I would say `buy new’. Neither would I recommend this person to drive a Wrangler without airbags. I hope this helps and thanks again for asking!
Hello sir. Would you suggest the same mix to romove heavy rust from concrete?
Yes it should work but best is to try since concrete is alkaline and you need to have it acidic after you have mixed everything
What about the danger of Hydrogen embrittlement weakening the bolts?
+Robert Ferguson it takes days for the hydrogen to penetrate deep into the steel according to all scientific reports i have been able to find. Not 30 minutes. The strength has primarily been reduced from the lost iron that went into rust. Thx good point comment!
@@Ken_Sweden Thanks for the reply Ken. I suppose 30 minutes is too short a time.
After 30 years maybe it's time to get new bolts ? I'm pretty sure any machinist can remake them to the same specs, (same bevel and stuffs..)
What's your starting HCL concentration?
Maximum 36-37% - and then 30 ml of it in 100 ml water
Question. If there is still rust areas and say a paint/ clear coat is applied for rust prevention. Does the already rusted areas that were not removed continue to penetrate the metals' integrity, or does the the paint (rust specified paint) fully keep deep rust from damaging the metal?
Rust forms as a consequence of iron interaction with water. Now, if you paint or clear coat your part so absolutely 0.00% water gets in under the coating, the remaining rust won't do much in converting iron into rust (iron oxide). The problem is that such paint or clear coat does not exist. All paints and clear coats are letting through a little bit of water with time, and it is referred to as 'permeability of plastics'. The 'permeability of plastics' explain why you sometimes get your medicine in aluminum sheets. That is because the drugs are very sensitive to water (humidity), and the suppliers want to be sure that no water gets through during the shelf-life of the drugs. Aluminum is completely impermeable. What folks do in the car business is thus to use the best possible option, since they cannot seal their cars with aluminum. They remove as much rust as possible because the rust in itself attracts more water than pure iron does, then they use paint (rust specified paint) that contains zinc because the zinc reacts with water before the water reacts with the iron (as a sacrifice metal). Some companies claim that they have the coating/paint that is completely sealing out the water so they don't need the zinc in the paint, but that is not true since no such paint/coatings exist. However, there are better and worse coatings towards sealing out the water. So, basically the answer is that no painting/coating will forever seal your iron against water but with a good coating you will make new rust formation happen much slower. If you also have the zinc in there, it will take even more time for the conversion of iron into rust to happen, but even in this case there is a day when the zinc has been consumed and water will be there again. Thanks for good input!
when it comes to cleaning you have level one ,level two or level three .. etc .. oxygen and moisture must be present to create rust. paint will stop both from getting to the metal but when the paint gets old and fails then rust starts . rust will destroy a metal and it will take some time .. how long has to do with moisture ,salt, oxygen ..no Mather it takes a long time for metal to fail in most application ..for a bolt to fail in a car you have approx. 10 years or more .you can use anode to slow the rust problem .
Why dilute it? Why not use pure?
I will show that too, but as pure it is mostly gas
Safe to leave over night?
+Albert Thane I left a railway nail from my other videos in there for 2 weeks, believing it would eventually complete dissolve, since some comments on this video state concerns on hydrogen embrittlement and migration of the acid into the bolts. In reality what happens is that the surface is passivated by a black ferrihydrate layer and then the rust removal reaction stops. I cut the nail up and it was perfectly shiny solid steel after a week. I would not use more than necessary I was to trust the bolts as it high strength bolts.
I have used evapo-rust and its beyond fantastic.
Deox C is better
The problem is that this process removes material and will now not hold as well during vibrations.
Hello, Regarding the "PH" in the PH scale does that stand for "presence of hydrogen" as I have recently been told? Good topic in your video. I am always interested in fighting rust. Take care. Doug
Douglas Thompson sorry Doug, I missed your comment. The answer is that it basically means how much hydrogen atoms you have as hydrogen ions in your solution. However the p doesn’t stand for ‘presence’ of the hydrogen in the solution. The problem is that the concentrations range over so big numbers, from very small to extremely large numbers, so someone had to figure out how to get it on a scale from 1 acidic to 14 alkaline, without 50 millions of digits after a comma. And to be correct the p stands for the negative logarithm of the H (concentration of hydrogen).
Potential of hydrogen =PH (nerds huh?)
How about adding some ammonia and making some licorice when all done?
Fasteners, unless made of exotic materials are not expensive and using old fasteners cleaned up with acid is not a good idea for several reasons; firstly the clamping surfaces are damaged and will not provide even pressures, secondly the threads will be rough and will, especially if being screwed into a soft material such as aluminium, damage the female thread and thirdly the torque applied to the fasteners will be incorrect (due to the first two points), especially if the overall diameter of the faster has been reduced. For wheel bolts, it might not make much of a difference assuming the hub is also steel or iron,, but for any application that requires a specific torque and/or is being used in a soft material, it's better in the long run to use new fasteners. Nice little video though.
Good advice.
To that I'll add that in dynamic application where there is load cycling, the potential of FATIGUE FAILURE increases with the length of in-service life of the fastener/material. All structural materials have a 'fatigue endurance limit' for use in cyclical load applications - for most common steels, typically at 30% of ultimate tensile strength PLUS about 1 million load cycles above or near that 'endurance limit'. Exceed that endurance limit and most assuredly the part/component/fastener WILL fail, and catastrophically without warning. Fatigue happens along the macro 'grain boundaries' of the metal, weakens the material ..... and in corrosive service (consider wintertime road salt), allows chemicals, salts, etc. to enter INTO and along the metal grain boundaries which then propagate internal corrosion of the metal for 'further' weakening. Imagine if your bolt has begun to develop micro-fatigue cracks and you then 'soak' them in muriatic/hydrochloric acid and that acid has penetrated into the base metal via these microscopic CRACKS.
For critical structure and their 'fasteners' in cyclic load bearing service, the best course is to ALWAYS replace the fasteners with NEW (to the exact same LOAD rating). That way your control arms, steering links, your 'hard' brake lines, your calipers, your engine/transmission mounting bolts, your 'universal joint' bolts, etc. etc. won't fall apart/off at the least expected timing.
If you really want to clean the rust from a bolt or stud (or steel tool), etc. there's a much better and simpler way:
Firstly a brief clean-up with a rotating wire wheel to remove the 'loose stuff'. Followed by - *BOILING the part in plain WATER* for a half an hour or more (the longer 'the boil', the better). What will happen is the remaining RED (ferric) rust will begin to convert to BLACK (ferrous) rust. RED rust is destructive; BLACK rust is 'protective' - similar to the 'blueing' finish on firearms. Lastly & after assembly, spritz on some *BOESHIELD T9* which is a wax-like metal protectant ... used extensively on aircraft and other 'critical' maintenance venues.
Hope this helps.
www.amazon.com/BOESHIELD-Corrosion-Protection-Waterproof-Lubrication/dp/B001447PEK/ref=sr_1_1?ie=UTF8&qid=1522078033&sr=8-1&keywords=boeshield+t9&dpID=417rK6tOOoL&preST=_SY300_QL70_&dpSrc=srch
Great point, as clamping force is the main point of fasteners. I've seen many machinists use Evaporust to remove rust without impacting the structure of the part being treated. They even use it on parts that are precision ground/scraped.
Ive used rusty bolts for years and years never had any failures.
So have I, but I'm pretty choosy about which to use again and which to discard - I wouldn't use de-rusted or reclaimed cylinder head suds or bolts, for example.
greenspiraldragon there cheap use new ones.
HCL is the best But the smell is unacceptable.
How can I get rid of its smell?
can you do this on a surface like a car body panel? obviously without having to drowned the whole panel.
It has crossed my mind that a paste with acidic components/chemicals inside would have been a nice thing to paint on and then blow it off with water. Possibly there are already something like that, and maybe that is what they put into rust converters. They are called rust converters but surely there is noting in rust converters that brings back the original iron, its a scientific impossibility. The only thing that brings back the iron is electrochemical processes that would do the reverse to what you see in the video, but then the problem is that the iron formed is not as strong as the original iron because it becomes porous. Myself I stick with this, and if it's too corroded resulting in too much pitting showing after acid elimination, then I only replace the part. On a panel you could just paint on the acid solution and let it sit if its flat but be careful with the acid and make sure you neutralize the surface after. The surface you get is perfectly fine to prime and then paint. Good luck and thanks for your comment.
boo boo tell use more about this process. Do you think that would work on a car frame?
I use large Rubbermaid watering tubs for larger items.
May I ask, what molarity or molality was the acid?
About 6 molar so there is a bit of window for heating if want it to go faster, this was at 20 Celsius 👍
Thank you for the information.
Great video. Do anyone know if I have to neutralize OSPHO ( phosphoric acid) after using it on the car chassis before I paint? not concern about paint adhesion but acid eating away the metal longterm.
The part that adds to corrosion in the long run, from reminding acid, is relate to the counter ion. If you would have sulphuric acid, then it’s the sulphate group, if you have hydrochloric acid then it’s the chloride group. In this case of phosphoric acid, then the phosphorus group is bonded into the new surface so rinsing is in most cases good enough and the phosphorus group as bonded into iron phosphate is not catalyzing more rust
@@Ken_Sweden what if I don't risen phosphoric acid before painting? Will it corroded under the paint?
So is this 100% or 37% hydrochloric acid thanks
100% is only existing as gas. The highest concentration existing in liquid form is 37%, rest is water. Boiling this 37% liquid will release 100% hydro chloric acid as gas, but it will immediately be diluted with air. I took the 37 and doubled the volumer with water so what you see is a 18.5 % solution. The reason i did this was because the 37% fume of so much corrosive acidic gas that it would blur the lens.
Thank you very much for the info I have my late fathers auto tools that has some rust on them I was told to use distilled Vinegar and water but your way looks like a faster way again thank you.
Wouldn't a dip of these bolts in used motor oil do the same thing to prevent rusting in the future? Makes sense to me, I am not confident of WD40 to be honest.
Torch em first and you re set for lifetime. Thanks for input!
I'm restoring a couple of cars and have a lot of rusty bolts and small parts etc. The carburettor cleaned up like new by soaking overnight with vinegar but vinegar was only so-so with bolts. Citrus acid works well with cleaning bolts but I was busted by my wife boiling bolts in citrus acid in her best pots. Today I've tried Hydrochloric acid and it is by far the best. Cheap to buy and sorted bolts in about an hour of soaking for 10min then wire brushing then soaking again. Only issue is the grease/oil that ends up covering every items and reduces the effectiveness
of the acid. Has anyone got a solution for removing oil?
For steel and iron, you can do a mix of 40 grams caustic soda + 25 grams of sodium carbonate + some detergent (all per litre) and then heat it so it simmers.
Let them sit in there for 10-15 min. This is basically the toilet cleaner + washing powder + liquid hand washing detergent. However, be aware and definitely use eye protection. Lots of folks believe acids in the eyes is the worst. That’s not true, alkaline (like the above) are the worst. If you splash this - your vision will be instantaneously, irreversibly and permanently blurred. You cannot use it on aluminum or zinc, it will erode your metal. If you want to go solvents, the stoddard solvents are the strongest but road tar is often too tough sitting, and I have had limited success. In the old times they used chlorinated stuff in there, which is banned today. This stuff is still used in some paint dissolvers but it is very nasty - it’s carcinogenic. For solvent based I recommend normal petrol (gasoline). I am always surprised how well it dissolves stuff and I have no clue what they put in there. Good luck.
I think if you're working on the body of the car phosphoric acid is better to use. Safer to use and it has a thicker consistency so it's easier to brush on.
I just threw away and replaced those bolts on my YJ. Had to replace the transmission skid plate too.
And where are we supposed to get the hydrochloric acid?
Everyone Can Do DIY projects Any hardware store w focus on painting - the 30 % does the job equally well.
Isn't Muriatic Acid (used for masonry cleaning, etc.) the same acid? Its available in most hardware stores and home centers in the US. Perhaps its already diluted?
A 37% hydrochloric acid makes fumes like smoke when u open the bottle. 28-30 from paint stores don’t produce theses fumes at room temperature. A 30 % would need 1 cup of water per 3 cups of acid to reach same condition as in this video.
First thing I thought of also!!!
Another way of doing the same is to use "White Vinegar" it is cheap, common and above all much safer , it takes a little longer as well
These fasteners need something for the oil to stick to or they will rust again in a year or less. Gun blue works pretty good, or simply let them flash rust and boil them for a black oxide then oil them.
Lay them on thier side for less wasted volume as you cover them in liquid. Forget the water, just use hardware store Muriatic acid. been doing it for years.
I believe adding hexamine to the hydrochloric acid will stop/reduce the rate of acid attack on the bare steel. We used to use this solution when cleaning hardened concrete off of the steel concrete mixers in the Concrete Laboratory when the students hadn't bothered. That is a lot of concrete in one sentence! Apparently the hexamine attaches to the bare iron but not the iron oxide.
Brilliant input, someone said that as well some time ago but I lost the link.
Never saw bolts like that on my two YJ's
I have on my '92 (harsh climate)but hell, I can replace the whole suspension soup to nuts for 500$ stuff your acid BILL NYE!😁
Probably volkswagon lugs
They look similar to the lug bolts on my wife's '19 Cherokee. But they also look like the ones on my '74 VW type 1
Now inmerse your full Jeep ;) Thanks for the channel I'm surprised about your other vids.
+ΓΛBIПθΓθJθ I’m on my way! 👍
What % hydrochloric acid? I see its 50/50 with water.
Roughly 16 👍
Great video,however the average house hold does not carry on hand sulfuric acid, nor do we know where to purchase it.
It’s muriatic acid in the paint store. Thanks.
It just seems easier to hit the metal with a wire wheel then spray it with RP-342 "HEAVY" Military-Grade Rust Preventive Aerosol Spray.
Rather than a 2hr wait they'll be ready in 10 minutes.
Just saying.
+Cherev Kodesh interesting, have you got a link? Please post!
Never made a vid about that, I'll consider it.
I'm less concerned with removing rust than I am with removing rusty bolts.
you better think again, if you don't remove the rust, the rusty bolt overheats when trying to remove and it breaks! bad news.
@@31acruz at that point it's better to replace the hardware.
@@chinchillaintheheat2641 exactly, and if you try to remove that nut off the bolt to replace it without removing the rust from the bolt.. you will break it. Unfortunately some of these bolts like a rear fascia mounting bolt are welded to the frame, you "really" can not afford to snap that bolt and break it. You have to deal with the rust or you will break it.
Are there any I'll effects of using this method to derust a car frame and the suspension? I plan on building a tank to soak the parts an am torn between citric acid, vinegar and the hyrochoric acid. Let me know what you think. Thanks.
In principle, all the rust you remove has no strength at all in itself. If you would go to the shop and buy rust dissolver you would likely get something based on phosphorus acid. The reason is that chloride, as in hydro chloric acid, can bond and stay with the metal (iron) and its corrosive there as well, that is if you expose the parts you have cleaned to water, i.e. in the future. Nothing beats hydrocholoric acid in efficiency though, and if you have used it you should make sure that you treat the part in an alkaline bath as well, to neutralize the chloric acid. I have no issue with using most of the above bolts again, because if you think about it, I have only removed useless surface rust. On one bolt in the video, you can see that the neck has rusted away extensively. This bolt was thrown away. There is no good reason to compromise safety. Good luck! PS. If you chose any of the other acids you mention, a bit of heat will speed up your progress.
Got it. Thanks for replying.
I have used phosphoric acid to clean an old gas tank and it came out like new! I dropped nuts & bolts and a few feet of an old tow chain in there and me and my neighbor shook it like hell to agitate it. Got the acid at home depot in the garden section. ✌
Better to boil them in vinegar, as HCl penetrates the structure of the bolts and weakens them. Acetic acid attacks the rust, but doesn't damage the metal of the bolts so much.
I have tried freezing vinegar and remove the solid ice (water) as prep the vinegar to increase the acetic acid on rusted bolts with results.
very nice. You cant get that degree of clean with a wire wheel. Good Video!
Good Video. We get the same results with SlurrySafe AR With no corrosion, pitting and safe to the skin
Will it affect the integrity of the metal or Strength of the metal?
Can I have it 1:8 (1 part HCL 8 parts water) and leave it for 24 hours without the solution eating away my metal?
It is much much more difficult to dissolve the iron in itself than the rust because the rust is porous if you would look at it in a microscope. However, since HCl is very active I would not just dump it in there and leave it. Based on the results I had on 50:50 you are 1/4 in concentration so possibly you would have the same result in 6-8 hours but it is also dependent on the nature of your rust. If it is very porous rust it will go faster. I would try and see what happens after 3 hours, the eating of the metal is very slow and the reactions slowed down at the end when most of it was dissolved. It's however always important to neutralize your metal object surfaces after the rust removal by using some sodium hydroxide of similar alkaline chemical. Cheers and thanks for the comment!
Hi Ken, Thanks for a very informative video and response. Unfortunately, I have to work blind on this one,as I have placed the solution inside an old air compressor tank which had rusted away for years of use. The tank has only small holes 1/2" and 3/4" inches on it, hence, can't really see what's going on inside. With this I can only hope and guess perhaps that it has done it's job inside there.
I have tried to pick a borescope / endoscope whatever it's called on ebay, but it will be weeks from now until it arrives. I've place the solution (1:8) yesterday evening, hence, it'll be 24hours when I get back tonight. I hope it hadn't really eaten through the metal now as hours had passed. (crossing fingers). The muriatic acid by the way in it's label says (15% HCL, 85% Aqueous vehicle), Aqueous Vehicle probably is water?.
This is why I'm asking if it had ruined the integrity of the metal as I have left it longer than your experiment, although mine was (1:8) solution as to your 1:1.
and yes, I have prepared baking soda, and will dissolve it in water upon flushing out the HCL solution.
After the soda solution, I'm planning to flush again a rust converter inside, basically, shaking the tank so the rust converter covers the inside surface area of the tank. Maybe top it again with red lead after the rust converter dries.
I would do it in turns of 2 hours, eventually your tank will be clean :-)
First Fix0 hope it worked sounds like quite the project
I have always been curious what the "rust converters" are. I noticed that an additive to most of these is poly ethylene glycol but I have read that it is also an acid.
What is the best way to coat iron after being treated besides priming?
I remember reading some old 1800's artillery books and they described a process used to coat cannons on ships, so you know it had to work being near salt water all the time.
The best way to treat iron if you wish to prevent rust is to look at how experts are treating iron in historical monuments. They use something called in Swedish 'blymönja', which resembles something like a 'lead paste with tar similar properties'. This sort of rust prevention is banned in many European countries for private citizens to use because it contains lead oxide but allowed for historical restorations. Lead oxide was dominantly mined in Spain in the 18 century and I would not be surprised if this was used in some cannons or ships coatings .
Rust converters are based on tannic acid, from tree sap, a very particular acid, in the old times they used this acid as in wood shaves to put togehter with the tools in the toolboxes, to prevent rusting. However, tannic acid is a weak acids, and therefore they complement with phosphoric acid to speed up the conversion in rust converters. Here i show phosphorous acid as compared to the above: ruclips.net/user/edit?o=U&video_id=5Bkdej_z1HI
can you agitate the bolts?
Crossed my mind but after pooking a bit in the rust, as I did the acid comparison in the other video, it seamed the process is both fragmentation and dissolution so it basically falls off and dissolves at the same time. The dissolving is the stuff that takes time, the acid needs to work it’s way into the pores of the rust, so I am not sure the shaking or agitation would do much. Agitating with some acid resistant sand, ...?? but then there’s the issue w the messy acid. For other parts I do, a small temp increase of conc increase is more effective in speedin it up
Vinegar works just fine and doesn't compromise the metal.
Not as strong as HCL
Why not phosphoric acid? I usualy use a product with 25-30% phosphoric acid and the rest is simply surfactants and soap, just in case you want to scrub it off instead of waiting for hours.
+PrinssiFO because of too high pka value
ruclips.net/video/5Bkdej_z1HI/видео.html
Rust is a mix of FeO and Fe2O3, along with bound water.
Phosphoric acid will react with the rust and form Fe3(PO4)2 and FePO4, both of which are insoluble, so will coat the iron and NOT color the solution.
In effect, the rust will be transformed and just seem darker.
In that video, it sounds like you were expecting it to dissolve the rust.
I would add some phosphoric acid to the mix.
Will this work on other bolts as well? Or just YJ? I have a Chevy
just let it soak in an alkaline solution afterwards! ;-)
MegaCrocketto the whole truck!?
Jacob how old are you?!
6, would you like to be my friend mysterious man in cargo van with candy?
Old Chevy or later Chevy? Elevation? 2door or 4? Diesel or gas?These variances will affect the overall outcome.
The chemistry method is easier, but a steel wire brush and a little muscle power would do an acceptable job getting that rust off and much faster.
This method after drying may produce more rust Over time unless you keep up on keeping them clean and protected with a oil over time
You’re right. Thx for highlighting
I hoped for more from a chemist. There are chemical methods which spare the iron and only remove the rust. I would have liked to know what these were.
Thx will do so, have to find a good reference for comparison so we can compare w and without
@@Ken_Sweden thanks i will sub and look out for it.
What molarity on the HCl?
+Carlos Rodriguez 15 M 👍
I believe you could use 'Muriatic Acid' from the paint or pool store, although it is less concentrated if I remember correctly. Nice work. Is this your hood at work or personal work space?
Indeed, you are right about the Muriatic acid. Muriatic acid is a less purified hydro chloric acid sold as 30% instead of chemically pure maximum concentration 37%. This difference has no relevance and Muriatic acid would do the same job, and in fact only mixing 1 part Muriatic with 2 parts water would practically work equally fast. This experiment was done in a professional lab hood, my personal, for using in my teaching activities at the university and it is very well ventilated. I would not do this inside my kitchen at home, but at the same time wouldn't hesitate doing it outside my garage if all precautions are made. After all, Muriatic acid is sold openly and there are much worse things out there. Improper handling of firecrackers or fuel from the petrol station, for example.
+Ken - It is terrific to see someone provide practical, knowledgeable advice for home projects. Keep up the good work and videos! :)
2.5 hours?
It's cool and all but I'm sorry I don't have that kind of time.
15 seconds each on the wire wheel of my bench grinder.
I completely agree! The only time I use muriatic acid is when I'm looking to dissolve the sludge and rust in an old gas tank.
For lighter rust on smaller objects, sure, wire wheels are just fine. I'm confident it'd take more than 15 seconds a piece for anything with heavier rust.
That’s ok if you only have a couple of bolts. Using a wire wheel
This also works to remove rust stains from fiberglass. It solvates the iron oxide so it can dissolve into the cleaning solution to be rinsed away.
works
but oil is not the best idea on wheel bolts
I read in a different comment that these are crossmember bolts.
Really strange, I've never seen these on a jeep YJ. They do look a lot like lug bolts like a lot of European cars have.
I still prefer electrolytic rust removal. It is easy to make your own setup. And you need nothing harsher than some water and bicarb and a car battery charger.
For all us non chemist mechanics out here:
1) what is the molar concentration of the acid solution?
2) what temperature did you conduct this redox reaction at?
3) what is the effect of substances on the metal substrate which are not soluble in polar solvents?
4) what are the consequences of the presence of chromium in the reaction?
5) är din Jeep Wrangler nu en EPO traktor?
Thanks Derek. Excellent input. 15. The temperature is room temperature. Paints, oils and silicone block the reactions. This is not stainless, and I am not sure why you ask about chromium. Always. Cheers!
Ken Sweden I was skojing a bit. About chromium, I know that toxic chrome salts are released during electrolysis and wondered if the same was true here.
HCl works great but why not Acetic Acid. It will take longer but you will get same results.
Dangerous acids make better videos.
It would have also been more exciting if he added water to the HCl rather than the correct way.
What about a 50/50 concentration of Phosphoric Acid and Water? That is what I use and it works faster and better than HCL. I am also an organic chemist.
03:54 Start the reactor Quade, start the reactor.
Awell filmed.Thankyou
The metal looks kind of sandblasted as if the acid had reacted with the base metal. However, maybe they looked that way before you put them in the acid solution?
true, but the sandblasted appearance comes from the rust that has been dug into the surface and then was dissolved. materials scientists call in pitting.
its a surface effect of the metal, just a scrape on it and it becomes shiny. I show it here:
ruclips.net/user/edit?o=U&video_id=5Bkdej_z1HI
After this process you should have run a blow torch over them to get rid of the acid. I would have rinsed in baking soda (strong base to neutralize the acid) and then heat treated to parts with a flame. This is actually how a chemist would do it.
Considering that these bolts have such an important safety role, it's probably better to just replace them.