Heat Treating, general discussion

Sorry guys, I can't find the info I need...I need to shorten pull type coil spring from about 23" to 20" and reuse it. The spring is about 2" diam. with 5/16" stock. Any tips for heat treat? All I have found is how to make knifes out of it ...LOL.... 1162 threads on coil spring.....Thanks Dave

I constantly read that bronze/straw oxide color is for cutting metal and blue/purple is for cutting wood. But why wouldn't full hardness be just as good for woodcutting? I get that a softer metal is easier to touch up, but wouldn't a harder edge last longer and wouldn't your time investment in sharpening be proportional to the longevity of the edge at the end of the day? What gives?

Hello, I'm new to the site, and fairly new to smithing.. Ive been knocking out some knives from beat up old files and some decorative items from mild steel, but nothing major yet.. A friend from the hardware store gave me a big long coil spring from a garage door the other day. I lopped off a 6 inch piece yesterday and Thought I'd make a little flint striker while i was goofing with some other stuff, I got it all shaped and quenched in oil from just above nonmagnetic... It wont throw a spark at all.. I've make a few with file scraps and hardened the same way and they spark fairly easily.. I sanded the striking surface afterwards and even changed rocks thinking I was cr…

My question has to do specifically with drawing a temper. I think I have a clear grasp on all the procedures up to the final step. In previous posts, there has been mentioned drawing a temp of approx a 1,000 degrees and holding it there for the required time (depending on thickness) and then a gradual controlled cooling. I have access to a small programmable kiln, so I am able to do so. One of my questions is, if I use this method, it seems the tool will have the same hardness throughout, from end to end. All my experience with drawing tempers on other tool steels involves leaving the struck end of the tool in a softer state that the working end. I ask because I'd like to…

I have fashioned a set of skid shoes for a snow blower from the original shoes. I employed one ton pickup truck leaf spring. Bent the ends up at a 40° angle and welded them onto the original shoes which are low carbon and very narrow/short. Now I have 3" wide shoes and 6" long. I'd like to harden them. Can I essentially heat them to non-magnetic and quench in oil? I would imagine the mild steel angle iron original shoe plate will not harden but the spring steel will. Correct? I guess I am concerned about the mig weld holding the angle iron to the spring steel. I don't want the difference in material to cool at a different rate and split/crack from the spring steel. …

Can anyone provide me the details about which material we should use as punch for the hot forging of 5135 material.

I just picked up a new to me Rockwell hardness tester today because I am planning on doing more of my own heat treating. The things I most want to bring in house require hardness testing results submitted to the customer with the parts.. After checking the calibration with the test blocks, I was eager to try the tester out on something so I tested a couple of things around the shop. I was surprised how soft a number of things were. A piece of mild steel did not even register on the RC scale I would have had to use the B Brailer and weights. I then tested a couple of drill bits. Hardware store drill bits were only 38RC and some good quality were about 42.…

Hello team. What's everyone on a good source of temp sticks/crayons for heat treating. My iron maxes out at 600 degrees.

Hello, made a spring swage for tenon work and would like direction on how to properly harden, as this will be used under a power hammer. Thank you

I am making some drill steels for single jack rock drilling competitions that I compete in. I am making them out of 1'' hex digging bars that are high carbon steel supposedly? I have made a few on a little lathe that I have but I am having trouble tempering them. I need the chisel end as hard as i can get it with out breaking and the end that i hit with the hammer to be hard enough not to mushroom. I tried one in a coal forge my buddy has. Heated the whole thing to cherry red then quenched the tip in water for about five seconds then pulled it out for about a minute then quenched the whole thing for about five to ten seconds then let air cool. When I struck it a few times…

Does having a Nitrate based low temperature salt pot in the shop increase corrosion in the shop? I am reading conflicting things about this online, but I wonder if some of this is nitrate vs chloride type salts? Now that I have some more space in my shop I want to bring some of the heat treating I currently send out back into the shop. The one I want to bring in the most is heat treating the pry bars I forge in the shop. I want to austemper them in salt right after forging them. The reason I want to do that is they are forged from Pre hardened 4340 (around 35RC). The end that is forged has to be hardened to 50-55 RC. I keep a short heat while forging so I don'…

At the steel yard today, the owner threw a 2ft X 3 foot piece of A/R (abrasive resistant steel plate) in my truck. You got to love free!!! Can this be welded to a mild steel base to make dies for the PH and hyd press? If so, can you share any thoughts on pre/post heat etc? or other uses. Funny, I didn't know that I need this piece of steel until I got it. Now I've got to put it to good use. What a terrible responsibility.....

Hey guys, I've been working on a crossbow for a client. If anything, I've learned being self employed is pretty crap. Anyway, I'm using whats about a 1/4 inch trailer spring for the prod (bow portion). I made a mismeasurment along the way. Without thinking, I filed the spring. As I did so, I realized it should actually be very difficult, but the file has no problem scoring the metal. for the moment, I will continue working. is there something wrong here? it has been sitting in the garage for a few years, but can a spring lose its hardness? Am I fine, or am I throwing it in the forge?

By way of introduction, I'll just say that I am a student and I am here because I have some heat treat questions that I hope somebody can point me in the right direction...I am currently taking a materials technology class. For a lab, we were given 5 steel specimens of various shapes: 1” round, 1” hex, ¾” hex, 1” square, and 13/16” square. Each sample was about 1/3” thick. We were told that each shape corresponds to one of the following steels: 1018, 1045, 4140, 1215, and 8620. For the lab we were supposed to test the hardness of each specimen, then heat treat them, then test the hardness again. Finally, we are supposed to match each shape to the appropriate steel ty…

Can somebody explain why I bothered to copy the "how to" from this site on the hardening/tempering of a coil spring square punch as it turns orange when punching through a nail header of (approx) 5/8" thick steel stock? I did drill the pilot hole. I did heat the header to yellow and punched it several times in small stages. Why harden the durn thing and then bother to draw temper???? One smith I have worked with years back said to make your square header punches from mild steel. He proceeded to make me one and a nail header. I was given the directions from this site to make them from a more exotic steel like spring steel or S class (maybe even H class) steel. Should have …

Can someone help me understand the difference between annealing and normalizing carbon steel. From my understanding both require the stock to be heated to the critical temperature and then cooled slowly. As far as I know in both cases the particles realine and the lattice is refined yielding a soft workable piece. Is normalizing just only used the context before heat treating versus before further working? Is their a difference and what is it? This may be a newbie question but maybe you guys can help me understand! Thanks! Caintuckrifle

I am finally going to get my anvil done, I convinced the manager at work to let me do it there when we are slow. I am wondering if anyone has ever used a pressure washer for the quench on an anvil. I have seen it mentioned before but only as theory. Do you guys think it will work or should I go another route.

So.... in the process collecting all my steel to move it over to my new shop..... I figure I have nearly 200lbs of S7 and D3 (punches and dies for tablet presses) I've been collecting this stuff for years and have never used any of it, I need to either learn this steel or scrap it. My question is; rather than annealing this stuff a few pieces at a time anyone reckon I can just build a large hardwood bonfire and cook the steel for x number of hours and achieve a suitable anneal?

Hello I want to work on a sheet of AISI 1018 which must have inclusions (such as MnS, etc) in its structure as much as possible. The thickness of sheet is 1.5 mm. Can I use annealing treatment to do this? or I have to use cold rolling for this purpose? Please let me know if you have any ideas.

I made a center punch for a friend out of coil spring. After a period of time, he said the point became dull. I'm not sure of the amount of use or abuse it took. I quenched it in oil to a golden straw color. In making a new one, I was thinking of using kasinet but didn't know if it would be best to treat it before or after running the colors? I think that if I treated it with Kasinet after tempering, I would loose some of the tempering. Before tempering, it might effect the tempering? Any suggestions?

Hi, I really want to start working with metal, the goal is bladesmithing, and I'm trying to get all the tools. Anvil is the next one. My uncle was kind enough to get two blocks of metal for me to use as an anvil, but they are soft. I know they are soft because I banged a metal bar with a hammer over them and blows left dents in the blocks. I'm trying to understand whether I can harden them and I'll have an anvil, or I can't. The only method I know of to answer this question apart from trying to heat treat them is doing a spark test. Heat treating will be troublesome here so I want to be sure that it has a chance of working before I do it. The tool I have for doing the tes…

I have few steel components (tool steel: E52100) and wanted to get them coated in order to improve their hardness and wear resistance. According to my material provider, company first quenches the steel, then performs tempering at the temperature in the range 185-190oC. The coating company has this process in which the temperature will rise up to 250oC, which is higher than tempering temperature. By heating, I know that the surface hardness will reduce but I am not sure about to what extent? After researching for past few days, I have been very confused as some sources says that the tempered martensite does not loose its properties (change back to austenite) until much …

Alloy steels need special homogenization annealing, but for carbon steel such treatment is not required. Alloy steels usually need longer time for austanisation (before quenching) than carbon steels. What are the reasons of this phenomenon?

I'm lucky enough to have easy access to a relatively high carbon steel around 1% I believe. I'm going to be making punches and chisels and have been trying to understand the whole heat treating and annealing process but it seems to evade me. What is the best down and dirty way to somewhat harden the punches and chisels? Is it even worth it because they will be hot punches and chisels and wont they just lose the temper? I will continue to read and try to understand this process but thought I would throw it out to you guys and see what you think. Here is a picture of the steel after power hammered into a rough tool shape. Th piece that was drawn out was from about a 5 inch…

Hey guys, Hopefully I am not going to upset anyone for the nature of my post, but I feel like this community would really be able to help me. I am brand new to the forum, partly because of a life interest in hand crafting my own knives/swords/tools, and partly because I work as a mechanical engineer at a plant that heat treats many automotive parts. I joined the forum because I stumbled upon it once before when I was curious about choosing a type of steel for a knife I was making for my father in law. I didn't join then but it was evident that you guys were knowledgeable in this field and for that reason I am back and seeking some assistance. I am not looking …