Hardening and Tempering a Chisel

welcome to the forge ladies and gentlemen today I'm going to take and show you a simple method of heat treatment of tool steel uh this here is a coil spring uh chisel that I made in one of my previous videos you can look for the links um at the end of this video to that I also have a punch that I made uh for you know your first beginning tools uh for the beginner and and I'll have both those Links at the end of this video uh today we're just going to go over the heat the hardening and the tempering of this it's a two-step process uh actually it's three-step process I lie the first step is the kneeling or normalizing the steel this has already been done and that's just heating it up to critical temperature and then letting it cool by the side of the fire and letting it cool back down naturally to where you can touch it um after that we're going to go on to this next step and this next step I'm going to bring it up to critical temperature and I'm going to show you what critical temperature is and what it approximately looks like as best as I can and then we'll go on to tempering and show you the tool in use thanks for watching all righty here we are at the forge so the first step in hardening this tool is you have to remember that you're going to be striking this in the hammered in with a hammer so this does not need to be hardened this can be left soft or as normalized so when I start hardening a tool to make sure that I get a good heat to where every to where all the grain structure in the tool is happy I start with heating The Struck in first I don't have to bring this this up to critical temperature I just have to bring it up to about a dull red and then I will flip it around and I will heat this end or the working end up to critical temperature and this end is the end that we will harden by quenching an oil I use oil um a lot for my hardening of different tools some coil spring you can quench in water it makes a harder tool but it's also a lot more risky so that's something to take into effect I suggest to all beginners to try to harden your tools in oil first the worst that's going to happen is it won't get fully hard and therefore your Edge will have a little bit of deformation that's easily reground or you can reheat treat opposed to if you do it in water you can end up snapping the tool and then it's not good for anything you have to reforge it out and go from there so first step we're going to go ahead and take a heat on this end get it up to right heat and then we will flip it around and I'll bring this up to critical and I will show you what critical temperature looks like all right here I am heating up the struck end of The Tool uh whenever you're working with tool Steels it is imperative that you let the temperature of the steel come up nice and gradual if you heat the steel too quickly you can shock the material or somehow or you can in other words you'll enlarge the grain structure of the piece and that will cause failure at a later date and we don't want that so you want to heat this real slow uh you can see some Sparks that's from another job that I had that didn't work out so well but I don't know if you can see that on the camera there um my wife is shaking her head yes I couldn't do this without her anyways uh back to this thing here as you can see it's getting to a nice like cherry red or a nice doll red temperature that's about what we want uh just enough that the that the grain structure in the struck struck end is very nice and relaxed for for the hardening process of the other end so I'll keep bringing this up to tell it doesn't take a lot of Air Blast to heat up tool Steels you see that's a little high but that's okay so now we're going to flip it around and this makes it very easy now that now we can heat up this end to critical temperature and once again you want to bring it up nice and slow if you bring it up too quick you can stress the material and your it will end up with your tool failing at a later date so we'll go ahead and get that heated and I'll get the camera rearranged to the Quint to the uh magnet next okay real quick before I take and show you you the actual um material and how it reacts with the magnet this magnet here came out of an old microwave that that wore out you can make you can get this out of speakers um a lot of different places or you can buy magnets online it doesn't has to be anything special um it just has to be a magnet and hold material so as you can see right now this is a cold piece of material and it sticks pretty good to this piece when you reach critical temperature it will not pull down to this piece or to this magnet so quenching or hardening the tool is is as much of a trick about time it's very time sensitive so once the tool is at critical or what you believe is you come out you check it if it's there you go straight to the quench you don't dilly dally over here you don't you don't want it to fall below the critical temperature because you're not going to get the tool hard so I like just setting the magnet on the Anvil like so you can leave it standing up whatever orientation doesn't matter but the PO important point is for the material to stick check to make sure your material stick into it cold and then you bring out your hot material and check it against it it will have a feel of almost like it just slides around and it'll have no pole whatsoever as you can see that pull straight to it you'll be able to put that that chisel Edge or whatever your tool Edge that's at critical right on the right on the magnet and it won't stick to it that's how you know that it's at critical temperature or it's a good really good gauge anyhow oh uh some guys can judge critical temperature just by I this is a lot more shed method for the beginner so this is what we'll do next and I'll show you how that I'll show you how that chisel doesn't stick to it and then I will let it come back up to critical temperature and we'll go for the quench so as you can see here this end of this coil spring is pretty tight you see it's just slipping around it's not really sticking to anything barely sticking at all uh there's no sticking but watch what happens as this tool cools down you'll end up seeing it actually stick to the magnet so I'll let it cool a little bit here I can fill it in just a little bit now so you can see by this demonstration that sometimes you don't need it as hot to be at critical temperature as you may think like right now it's just now starting to get a little bit of its pole back so that would mean that even at this low a temperature that would be the hardness or or or the the right time to actually quench it and uh get the tool hard now it's finally starting to stick so at that point you're not going to get a hard tool now that it's starting to stick but as you can see this is a really low temperature for this steel if you would have quenched with the steel at that at that high of the temperature the grain structure would be really large inside the steel and quenching at that it would lock that structure in very large and when you would go to use the tool it would just crumble or break or snap off so we want to have a really nice compact grain structure as you can see it's definitely stuck to it now so I'll heat this I'll heat this tool back up to that proper color range that I saw at at critical which was about a doll red for this for this particular coil spring and then I will quench it in oil all righty I've got the Chisel to the right temperature now the Air Blast is shut off on the forge I am going to take and bring it out now and go into the quench here's my quenching bucket full of oil uh this thing's been used a lot I still got a whole bunch of oil left in there uh and it's developed some moisture if you look at it it's kind of creamy looking your oil should look cleaner than that for best results this has just happened to get moisture from hot cold being in the shop uh but it will still work for this purpose I use it for most of all my tools so I have this up at critical now I'm going to bring it out we'll go ahead and go in the Quench and you'll see what that looks like so here we go you want to make sure you use figure8 patterns and get the entire tool in the oil if you notice it's putting off a lot of smoke so you want to do this in a very well ventilated area my shop is very well ventilated but you can hear that Sizzle and you want to take and keep it quenching until that Sizzle stops that's how you know that you've properly hardened the tool all the way or that it's cooled down enough that you can go onto the next step I usually after this step this is still very hot it would scge in a half a minute half a second if you if you were to touch it I usually like to leave my tool after I've quenched them set them on a wooden block or set them on somewhere that they cannot heat cannot be drawn from them from one side or the other so usually a fire brick or you know a pine block somewhere let it sit and let it cool naturally and then move on to your next step so the next step that we'll do after this is we will brighten this surface finish and then we will start heating the tool from the back and and bringing our temper colors up to our Edge to have a properly hardened and tempered tool okay we've got the tool hard uh we're going to end up polishing up this Edge a little bit for that I'll just go ahead and use an angle grinder off camera to just kind of just give it a real quick clean polish if you don't have an angle grinder you can use a stone of some sort um or just sandpaper and just Shine the Finish really anything so this way you can see the oxidization colors run to to the edge of the cutting tool um a quick check a quick test it's been as been around for ages is with a file a wor out file um I have my own reservations about using a file to take and check the material to see if it's hardened or not uh if your file is so wore out kind of like this one is it's not going to give you a very good test if you use a good file you're going to ruin the file if it is hard to actually check to see whether the edge is hard but considering this is the way the wise old sages say to do it this is the way I'm going to explain you to do it as well as you can see I've wore out most of the teeth back here but there's still some good teeth towards the front of this file and that's why I check the edge if you've got a hardened tool it should slide right off the material the file should if it's not hard you can hear that it cuts it cuts into the material so that's the difference you can hear that sliding or glassing over then you can hear the very different cutting sound on the soft part of the file so never mind that it's getting shiny here I'm just removing the oil oxidization off the piece uh the the end is hard but this is a good way of checking it um also you can brighten the steel that way not very good but you can um it is a good way of testing it as long as uh all your conditions are work out right um I suggest keeping a file just for this specific purpose uh and you know don't don't use a really good file to do it so all right right I'll polish this up and we'll go on to the tempering all righty so here here is the piece all polished up with the thing you don't have to have a real high polish in fact a lot of the times I do not go to this extent uh the most I do when I shine up my tools is I'll take them to the wire wheel and just wire wheel it up a little bit so it's a little brighter than just flat scale color and that'll allow that will allow you to see the oxy iation color just fine when you first get started doing Heat Treating it's good to work with a good clean surface like this so you can really get a good strong understanding of what is actually taking place on your tooling uh blacksmithing so much of blacksmithing is observation so do a something do a step and then test it and observe what is going on with the piece that you're working with uh same thing when I said you know about testing your coil spring some coil spring won't get hard in oil it just will not get hard in oil and this is not a problem say if you're making uh if you're making like a wood gouge or something that you're cutting wood with or another softer material that would otherwise have been cut just fine uh with a softer steel but with what I do I I like to use my tools on both hot and cold steel and to do so you need a ver a particularly hard tool to be able to make the cut into the steel and not deform The Edge so it's always a good thing to check and test and if the coil spring seems to take and like being quenched in water and everything works out okay after you've done the heat treatment there quench that particular coil spring and lo you can read on online forums guys bicker back and forth water oil water oil it really does not matter it just matters on what the steel that you are choosing to use likes so if you like quenching and oil if that steel reacts well with oil quench an oil if it reacts well with water and it suits your purposes do that onto the back to what we're talking about here it's nice and shiny we're going to go to the forge I want to see if I can't get a closeup on here so you can actually watch the colors run uh another way of doing this if you don't feel comfortable that you'll hit the right temperature in the Forge you can take and heat the heat back here in the middle of the tool with a rose bud or a torch of some sort little propane torch and be careful to heat it up slow and watch the colors run that way and it's a little more accurate uh a way of heat treating a tool if you're just getting started so over the forge we go okay so here we are back at the forge again um The Struck end of the piece is seated deeply Into the Fire and it's getting warmed up slowly very little Air Blast at this point in time we do not want we do not want the colors to run too quickly we we want them to come up nice and even and slowly if you see the colors run really quick what you what you have done is you have just essentially heated the surface of the material enough that you caus the oxidization but the entire tool through has not been heated and so therefore you have a hard Center and a soft outside surface area that's opposite of what you want you want the whole tool to have one nice even temperature as it comes up so as I'm sitting here I don't know if the camera can pick it up but right in here I'm just starting to get a faint bronze color almost a straw like color and it is slowly working its way up to the tip so I'm letting this heat up very very very very very very slow and what will happen is is this will slowly this bronze color will move its way up towards the tip and continue and you you'll slowly start seeing it turn uh different colors it'll go from a light straw color to a bronze and then it will move fairly quickly to a purple to a purplish color and then to kind of like a teal then a dark blue and then like a light blue and then back to gray uh if you get all the way back to Gray you've lost all your hardness so what we what we have done is this tool is at its hardest State and by drawing The Temper or pulling the temper on this thing we are REM we are removing the stress of this being that hard so way back in here on this Edge now I can see a purple forming I don't know if you can see that paintly there okay there there's a purple and a blue forming with way back here and a really dark bronze color so just bear with me those colors will start running up here once those if you notice I don't have the Air Blast on it's just heating the back end in the fire once these colors start running and you get the color that you want to start running up towards the edge once it's there you want to cool the working in down and stop the colors from running but I don't know if you can see them now see the coming up through the Chisel there m so as you can see it's starting to run that bronze is coming up nice and slow like we want it and that's actually the color we're looking for is this bronze up in here because we're going to use this chisel to uh cut Material off hot and anytime you're using stuff on hot cutting work you're going to lose some of your temper and your tool anyhow so it's always good to just stop at a nice hard tool temperature and let it go from there and it will slowly soften and you'll eventually have to retemper the tool but as you can see the whole surface is starting to turn bronze now so that's what we're wanting that's what we're looking for this color here we want that good deep bronze color and then we are going to stop it before it goes too far right there that's the color we want we're going to go ahead and quench it back in oil it is always best it is always best if you can take and let it cool naturally but there's no harm in quenching it off to this point either keeping in mind that you don't want to quench the end that you're going to be striking that's really super hot or that's at critical temperature you want to work this in an figure eight pattern and in and out so this way you don't get a hard fast line we just want to cool the tool off we don't want to harden the back end this will give it a nice natural temp temper to it and it'll look real good once we clean it off use a rag here I don't know if it'll show up now you'll get to see you see those colors there yep now you can see that there so that's what I wanted this tool to be I wanted it to stay fairly hard but I wanted to remove some of the brittleness um once the backend drops below your critical temperature excuse the phone here live filming once your back end of your tool struck in drops below its critical temperature you can go ahead and cool the entire Tire Tool in oil so that's below the critical temperature continue to quench continue to quench until you hear the sizzling stop in the oil that's how you know it'll be cool enough that you're done this process is essentially the same for anything that you want to make I don't care if it's for woodworking tools out of coil spring pretty much anything out of coil spring I use the same thing on 1045 1095 um except with those those are water hardening so I put them in water I don't usually quench them in oil but I use essentially the same method all the time for all my tooling uh you can do this for butchers you can do this for foolers of all sorts shapes and sizes take your pick I've got a punch that I had made in in another video for a beginning round punch you can do the same thing for that anyways thank you ladies and gentlemen for watching let me know what you think about this new video format uh in the comment section below and I look forward to posting some more videos like this and keeping you guys inspired happy smithing

Channel: Christ Centered Ironworks

Views: 688,467

Keywords: hardening and tempering possible process, tempering a chisel, hardening and tempering a chisel, hardening chisels, forging hardening tempering, how to harden and temper a hand forged round punch, blacksmith harden and temper, hardening and tempering process, hardening and tempering steel, tempering on hand tools, tempering tools, tempering steel, hardening process, hardening steel, tempering process, how to temper steel, hardening and tempering, metal hardening process

Id: __3vmtFFy3s

Length: 23min 46sec (1426 seconds)

Published: Wed Mar 22 2017