Heat Treating, general discussion

I just received this email from the ASM who produce the Heat treaters guide which is the bible of industrial heat treating and costs about $250. I don't have a smart phone so cannot currently download the app, but I definitely will be when I get a smart phone. Sounds like it is a free app and would be well worth downloading even if there was a nominal cost. Materials Park, Ohio - October 8, 2013. ASM International and the ASM Heat Treating Society are pleased to announce the recent release of the Heat Treater’s Guide Companion, now available in the Apple and Google App Stores. The free app provides ready reference data on nearly 170 carbon and alloy steels and i…

There have been many comments and options on which oil is best for quenching. Most say to stay away from used motor oil because of the contaminants picked up (presumably) from the wear and tear of the engine parts. Please keep this subject on used motor oils from vehicles. Does anyone have any hard evidence (references, URLs, test results, etc please) as to the contaminants contained in the oil and why they should be avoided? Just how contaminated is the oil? What happens to the contaminants when the hot steel is quenched, where do they go? If we can produce the evidence, we can eliminate the myth and opinion, and find the facts. The next question would be why not…

By Steve Sells taken from the book Knifemaking 2.0 and the IFI archive Here are a few quenchants and their relative speeds Brine, 5-6 seconds Canola oil, 10-11 seconds Chevron Quenching oil 70, 10.5 seconds Citgo Quenching Oil 0510, 14.5 seconds Drasta 119S, 13-16 seconds Drasta 117S, 8-12 seconds Duratherm G, 11 seconds Duratherm Superquench 70, 10 seconds Gloc Quench A, 11 seconds Gulf Super Quench 70, 11 seconds Houghton G quench, 10-11 seconds Houghton K, 7-9 seconds HP Metaquench 39 14.6 seconds HP Metaquench 42 14.2 seconds HP Metaquench 43 12. seconds HP Metaquench 44 8.9 se…

I'm still battling with my back pain issue and I couldn't do much else around the shop today, but I've had this old toaster oven laying around for a while now that I used to temper in, It's just not deep enough for some of my blades so decided to rip it apart, upgrade a few things and rebuild it in a larger, insulated shell. For those of you that may have wondered, there is no insulation in a cheap toaster oven, it's a miracle anything can be cooked in them in the first place! My main motivation is to use it for a tempering oven during my bladesmithing classes which start next weekend. We'll be hardening in the forge, but the steels we're working with require more than ju…

From Knifemaking 2.0 Another thermal process to address is called subzero quenching. The purpose of a subzero quench is to force the conversion of retained austenite after the initial quench into martensite, allowing us to get the metal tempered, rather than allowing it to remain as the brittle untempered martensite if it were allowed to convert on its own. The sub zero quench is mainly applicable to high alloy steels. The home freezer is not cold enough for more than half conversion. Crushed dry ice and acetone can result in a temperature drop to about -170°F (-110°C). A quench with liquid Nitrogen will result in a drop to about -300°F (-185°C) and is used for…

Links to the pinned Heat treat information, While writted for the thin sections of blades. ithese will get you a long way to the HT of your other projects as well. Introduction to heat treating http://www.iforgeiro...-heat-treating/ Advanced heat treating http://www.iforgeiro...-heat-treating/ Advanced methods of annealing http://www.iforgeiro...ealing-methods/

Hi folks, got a question concerning the cooling times in CCT. If you have a look at the diagram there are several curves showing the composition after different cooling speeds. Everything ok for me but how do i know how fast a cooling medium does the cooling? Are there any rough rules of thumb (e.g. cooling in oil does xxx K/s, cooling in water yyy K/s,...)? Many thanks in advance!!!

I am sure someone here has probably built a kiln before. I have Harold Hoffmans book with its plans for a minuscule kiln for heat treating pocket knife blades and springs. I also have David gingery’s “lil’ Bertha” book. Both are pretty old sources. I have elements, thermocouple bricks and a PID. The Hoffman kiln has an interior that is 2.5x4.5x4.5, which seems small. I have played with the bricks and have an arrangement that is 4.5x4x14. Is there anything I should be looking for in kiln size? Also, I am not familiar with PID wiring. Is there a good guide anyone can recommend?

I am in the process of starting my first set of rasp spurs. My question is, If you anneal the rasps before building the spurs, should you harden them when you are done? Trying to get all my ducks in a row before I get started. Thanks in advance!

I looked into Redbeard Ops' DIY heat treating oven build. It was a very thorough and and well done instructional video. When I tallied up parts--not including the steel--it was over $800. Of course, for what he built, it is comparable to very expensive ovens that are like $2500+. I can see why a knifemaker would jump on this project. But, I just want to do post weld heat treating of power hammer dies, and maybe some annealing of big chunks of metal. It's going to be nice to have for heat treating small Damascus knife projects I do from time to time. This oven is a lot heavier than I expected and seems well made. There's no ramp feature, so I have to use a …

I have been working on getting help heat treating a set of power hammer dies I have made. The Dies are roughly 2x3x4 (one is slightly larger). I did some research online and read the posts in heat treating. The following is the process I have come up with that I hope will yield the best results. If there is anything that you more experienced heat treaters see that might pose an issue please let me know. Step 1. Normalize the material to relieve stress. Heat dies to 1000-1022 degrees F for 2 hr. Furnace cool to 850 degrees F at 50 degree drop per hour. Then remove and place in vermiculite. Allow to cool completely. Step 2. Heat dies to sl…

Howdy all, just a small time WY cowboy looking for advise from yall. New to this forum, found it trying to look up heat treating info. A long time ago, needing a tap with none around to chase some threads a man showed me how to cut two grooves in a bolt, taper the leading edge, heat it red with a torch and cool it in motor oil. It worked, but doing some reading on this site brings up more questions. I have a small pile of old railroad spikes, might be from the 1800's. Not sure which exact metal they are but I need/want to make them harder. I am using them in a homemade harrow to bust up the washboard bumps in my gravel road. They are about 3/4" square, may…

I purchased some S7 from Mcmaster Carr to make some punches and hot chisels. The trouble I ran into is that it will not air harden. I tried in my electronic controlled oven first, held at about 1725 and took it out to air cool, but never got hard (a file bit pretty easily). I though maybe it was just decarb so i tempered it and finished up the grind. I tried the hot chisel to cut some material and the edge flatten out like mild steel. I tried to re-heat treat it in the forge, brought it just to about orange heat and let it cool but it is still soft. At this point I got irritated and reheated it and water quenched it. Hard as glass and during my testing I was ab…

So my question is, if I were to heat a piece of steel to a glowing yellow and then stick it in kaowool so that the whole piece is covered, would that slow down the cooling enough for the steel to be properly annealed?

Hi guys, long time no see. Life has been kind of crazy. I've had a little job come up helping out my local shooting club. They have a target that is made from 3/8" thick AR500 armor plate. Someone shot it full of holes with some kind of magnum and I want to try to fix it. Another guy already welded up the holes once, but his welding just tempered the plate and so everwhere he welded it the plugs came out and other holes showed up. I have a couple of questions. 1. What would be the best stuff to weld it with? I have a 225 amp buzz box and a 175 amp wire feed welder. Which rod or wire would hold up best and be able to be heat treated along with the AR500? 2. Once …

I think this is the right place to put this, although it is more a celebration of new possibilities than anything. One of my neighbors gave me 4 quarts of new 0w-40 motor oil and I spent the last hour testing out pieces of scrap that I had that I thought might be high carbon. With this oil and the capabilities it gave me, I finished making my first tool, a hot cut chisel!! I’m pretty excited, because now I feel like a “real” blacksmith! I should also add that I have actual quench oil on my list of things to buy, this motor oil just came to me and I decided to see what I could do with it!

Good afternoon all- A little victory of mine to share, as this group understands and appreciates these things (I'd share with my wife, but it's all Greek to her): I successfully heat-treated a center punch! This punch was inherited from my Grandfather, one of many tools that I could not do any of this hobby without him. This punch had lost its tip definition after light use, very flattened out, requiring a re-grind on my belt sander to a tip once again. On my Mr. Volcano forge, once up to operating temps, I had the punch on the forge for about 8 minutes at a orange/yellow heat. The punch went into the Fusion 10 quench oil immediately, gave it about 30 se…

Good afternoon from warm SW Michigan! I'm asking for anyone's personal experience using Fusion 10 quench oil, asking for real use experience and thoughts versus the old stand-bys of Parks AAA and Parks 50. I have already purchased and have been using the Fusion 10 quenching oil for various items I've begun to learn about heat treating in my home shop (a one gallon jug). So I've already committed, I'm not looking to be talked into buying Parks at this time. I also wanted to support a small business in Huntington Indiana that makes the quenching oil (Fusion Chemical). I cannot find much anywhere, on here or similar websites, of other Smith's personal review…

I've been figuring out how best to build a baffle to use for hardening knives in a propane forge. I need to get the heat as even as possible across the blade and since I'll have a PID controller connected to a thermocouple and the main gas valve I want to be able to control the heat quite accurately. I'm thinking a 1/4" thick, 3" internal diameter round black iron pipe section should give me decent thermal mass and help even out the heat. I've seen a few people mention that the blade shouldn't be touching the inside of the pipe. Has anyone done this before and got an idea for how best to support the blade off the bottom of the pipe? The main things I've seen people talk a…

New here, glad I am surrounded by some experienced people here. I have been forging for about 2 and a half years and have made and heat treated successful knives from 1084, and 5160, I have started challenging myself with a generic medieval crossbow and steel prod and have finished grinding tried hardening and tempered and even fired some bolts accurately from the assembled crossbow. However, unlike the 1084 I don’t think I’m hardening the 5160 like I can with the 1084 as files do not skate off the 5160 before or after tempering cycles. I have constructed a expanded volume forge from wood stove tubing and casted refractory cement that I intended to replace my last two fo…

Hi all, I needed to make a set of custom pliers, so I cut down an old set of 6” Kobalt pliers (the kind with the blue and grey slide off handle covers) from about 10-15 years ago. I annealed the pliers, drilled my hole and filed the heads, and attempted to re-harden them by heating the first half inch of the jaws to a cherry red and quenching in hot water. A file test seems to indicate they didn’t harden much if at all. Anyone know what kind of steel these are, or what the process might be to harden and temper them? They are made in China. I believe they came from Lowe’s. I didnt do a file test on them before I annealed them, I should have to get a baseline hard…

I am making an oven from soft refractory bricks primarily for heat treating aluminum motor cycle parts but will be able to go to a bit over 1000 Deg centigrade so will be able to be used for steel objects as well. I will also have a ridgidised kaowool roof and kaowool around the bricks as well as they are not a good insulator, the kiln sizes are 660 deep 400 wide and 230 high inside. I have used my die grinder set up to be used as a router with a 1/2in round nosed carbide burr to cut the grooves for the elements to go in. The elements are 3x3000 watts at 400 volts so it will be 3 phase. I had the elements made up by a company that makes kiln parts, i am doing this as I ca…

I have a bunch of antique pitchfork heads that were a barn that burned. They were to be used for the Scottish Highland Games, so they need to be able to withstand a lot of stress, which they were great for, before the fire. The tines are bent. I'd like to straighten them, but have no idea what I would need to do to heat treat them, to retain and, hopefully, regain some of the spring qualities of the steel. Any advice? Background on me. I've done a lot of welding and fabricating, but have no experience as a blacksmith. I would most likley do the heating and straightening using either an OA or oxypropane torch. I could do a primitive coal forge if needed though…

I am wondering if you use motor oil to quench if it all has to the same type or not. Can you use 0w-20 with 30w-40 as a example

So, after reading this (it appears that globalspec is not commercial website): https://www.globalspec.com/learnmore/materials_chemicals_adhesives/industrial_oils_fluids/quenching_oils_heat_treatment_fluids And watching Knife Steel Nerds discussing quenching oils: I've concluded: 1. You should not use Canola 2. Parks AAA and Parks 50 is pretty pricey. Importing it to Belize costs 2x due to shipping So, to avoid paying almost 500 bucks for Parks 50, have any of you found any article or tests done by anyone or yourself on other quenchants like hydraulic fluid? Ron Note that this question refers to quenching knives made out of …