Newbie questions about hardening and tempering

[jimmyw]

Hello.

I'm Jimmy and I'm very new to blacksmithing. I've recently set up a workshop and started to forge a bit. I'm very intrested of making hammers and I've watched a ton of videos on YouTube about pretty much everything there is somethings I just can't make clear and I hope someone can make them clear for me today.

 

First off, Right now I'm making a hammer eye punch out of an old cross peen hammer I found out in the garage. It's an old hammer so I guess it's been hardened and tempered before, right? So, do I need to normalize it before forging it? And if I got the normalize part right, I heat it up to cherry red and then just let it cool by itself? Or can I just forge it without normalizing it? Alright, so when I get to the point where I've forged out the punch and all, to temper it I heat it up to red hot, then quenching it in water. Then to anneal(?) it, as it's very fragile at this point I heat up a drift and place the hammer head over that until I get like a violet color on both sides?

 

I hope to get some help here as the only Swedish forum Antracit.se seems to be completely dead for many years.

I'm planning to make my hammers with C45/SS 1672 steel to begin with

Thanks,

Sincerely.

[Steve Sells]

try reading the pinned post explaining this THEN ask questions, after that we will be glad to help , heating to red will ruin any temper left in it

[jimmyw]

Alright. I've read "Introduction to heat treating" and it doesn't answer my question about normalizing the old hammer before I forge it into a punch. But if I understand correctly, I don't need to normalize it? Or rather, It normalizes in between my heats while forging the piece. In that case I can just heat it up, forge it as I want > Harden it again > temper. Or am I wrong here? 

There may be a language barrier here. 

But as I read the post, to harden it - Yes, I heat it up to critical temperature(where the magnet no longer holds) and then quench it fast in water. Then to temper, you mentioned to use an oven for example and pre-heat it. For my case I can't use the kitchen oven, but I've seen people on YouTube heat up a drift and then placing the hammer head over the drift and let it set.

[Latticino]

The process description seems very close, but you have misused a couple of terms so it is not always easy to understand you.

I forge my hammer eye punches from bar stock, though an old ball peen could work provided it is made of medium carbon steel in the first place. 

A simple process would be to  first spark test the head to ensure it has decent quantity of carbon to harden sufficiently.  Then forge to shape keeping the stock in the red to yellow range while forging.  Let cool slowly from last heat buried in wood ash or vermiculite if possible to anneal.  Grind to shape.  Normalize the steel by heating up to austenizing temperature and air cooling, then to just below non-magnetic and air cooling, then to just barely glowing red in dim light and air cooling.  Harden by heating to austinitizing temperature (a little bit above non-magnetic) then quenching just the business end in water for a slow count of 10 and pulling it out to autotemper.  To autotemper you "run the colors" by quickly cleaning off the still hot business end with a pad of sandpaper or piece of grinding stone  and watching the tempering colors run up to the tip of the business end.  When that reaches a straw color quench that section again in water for a short count and repeat the autotempering.  Repeat until the colors stop running.  I would then torch temper the struck end and eye to a blue to be sure they are soft (or you can use a heated drift as you note above).

Of course what you also will need is a hammer eye drift .  I like to make mine out of 1" rod stock (4140 or the like) with long handles for ease of manipulation, but some make them just long enough to bottom out on the anvil in use.

Hammer making isn't really a good early beginner project IMHO.  You would certainly be well served getting direct instruction in making hammers from someone who has done it before. 

[ThomasPowers]

No, no normalizing before forging is needed.

Yes normalize before hardening.

Depending on the alloy; hardening in oil may be better than water. (I generally start with oil and if I find it too soft, go to a brine quench.)

Depending on the alloy; the correct temperature/colour to temper too may differ---make sure the struck end is fairly soft! (Or use a soft faced hammer on it.)

[jimmyw]

21 hours ago, Latticino said:

The process description seems very close, but you have misused a couple of terms so it is not always easy to understand you.

Terms are really crashing between english and swedish and even more as I don't understand the terms, or rather how to use the different techniques. I can't seem to find just clear information like a step-by-step how to actually harden/temper any piece.

The reason I'm using the hammer is because that's what I have. I got the idea from Old Hickory Forge on YouTube as he makes a hammer eye punch from an old ball peen hammer. I don't have too much material yet so I'm using what I have.

 

I don't have a blow torch yet. I only have my homemade forge made out of an old fireplace, a anvil and my current hammer pretty much. I've made a pair of "african style" tongs and a pair of flat bit tongs out of rebar that works somewhat okay.

21 hours ago, ThomasPowers said:

No, no normalizing before forging is needed.  Yes normalize before hardening.

Alright Thomas. So Forge it to what I want it to look like, grind it etc > Normalize it (3 times as Latticini said?) > heat up the punching side > quench > temper it by heating up a drift and placing it on it

am I getting this right? 

Thank you all for help.

[ThomasPowers]

As I recall you are not the only smith from Sweden that has posted on here.  It might help to dig out others and try to get in touch with them to deal with language issues.

Normalize: heat above the critical temperature and let cool in still air. (Not all alloys require/profit from/can be normalized).

Harden: heat above the critical temperature and quench in the medium appropriate for the alloy, the item and your preferences. (May be done differentialy)

Temper: done IMMEDIATELY after hardening by reheating to a lower temperature based on the alloy, the item and your preferences. (May be done differentialy---some areas are heated more than others so the hardness may differ as well)

Steve; you agree with my take on it?

[jimmyw]

Alright so I've read on some other forums and they say you don't need to harden and temper Struck tools, so in that case what we've talked about already only applies to making new hammers or knives etc?

 

[Marc1]

When I check the terms for hardening and tempering in swedish, it seems they are used interchangeably like the case in Italian and spanish. Hardened steel translate into acciaio temperato in italian or acero templado in spanish. The hardening side of things is lost in translation. German seems to be more precise in the use of words, with Härten und Anlassen.

Considering that hardening and tempering is an industrial process not easily understood, this is not surprising. Add to it the secrecy around the process that shrouded it for centuries as if black magic, up to this very day it seems ... to understand what to do with your hammer forged into a punch, I suggest to read a textbook in your language that describes the process in detail. Sweden has been the capital of the best steel since the times of the Vikings who, if historian are to be trusted, improved their own steel with techniques and material taken from the arabs. 

A visit to your local state library will most likely yield good results.

Med vänliga hälsningar

[Irondragon Forge ClayWorks]

Welcome aboard Jimmy, I always recommend this thread to new folks to the forum. READ THIS FIRST   It will help with getting the best out of IFI.

[ThomasPowers]

JW the answer to if you need to harden and temper struck tools is YES, NO, MAYBE---depending a a lot of different factors. There is NO single answer!  There is no single answer! There is no single answer!

If you find a site that promotes a single answer then you are either not understanding all the variables they may mention or they are being inaccurate. Perhaps by merely not knowing enough about the subject; perhaps by trying not to confuse people. (Anyone who suggests the same heat treat for say D2, 52100 and 1040 steels is NOT to be trusted in anything they say!)

Most answers will depend on alloy used, intended use, shape/cross section of the item and personal preferences---some folks heat treat almost all their tools as they prefer them that way. Some folks will just normalize tools, (which is a heat treat!), and so use alloys where just normalization works.

Historically the term "tempering" was used to refer both to the hardening and drawing hardness in tools as it was generally done in one go---you did an interrupted quench and used the residual heat to 'draw the temper' in the quenched part.  Even now days it's strongly suggested to go directly to tempering after hardening so even though they are separate steps they are done one right after the other.  On this site we tend to break down each step and use a different term for each so as to not confuse them---so: annealing, normalizing, hardening, tempering, cryo-quenching, re-tempering may be referred to---but not all alloys will go through all the steps, some won't need them---why cryoquench a steel with minimal retained austenite? Others won't profit by them or they won't work---trying to normalize air hardening steels for instance.

Alloys generally used for hammer heads tend to be fairly low alloy medium carbon steels.  I would generally oil quench and draw substantially back for things like drifts and punches and in use I would quench them in water every 3 hammer hits of so to keep them cool and not draw the temper any further. Note that *old* tools may be higher carbon or lower carbon than what we may expect today!

HOWEVER; not having YOUR piece in my hands all I can say is you need to experiment and find out what works best for YOU!  This is the basic rule of using scrap steel rather than a known alloy new from a dealer where you know the specs for working and heat treat to get what you want.

[jimmyw]

I do want to say I really appreciate the help I'm getting from you guys. I also understand you get these kind of questions daily and It's frustrating. As your last message Thomas, you're right. I just have to try and see what happens. I mean, I can always harden the piece if I see it's too soft after normalizing it. I understand the harden/temper in the same heat so I will give that a try tonight after I get home from work with some pieces of square stock.

Again, I really appreciate the help.

[swedefiddle]

Good Morning Jimmy

Welcome to this site. Please post your area in your Avatar.

The language of Heat Treating; Annealing and Normalizing are the process that removes stress and strain from your piece, BEFORE you start to harden. Hardening is the process that locks the molecules together to form a VERY BRITTLE work piece, brittle like Glass. Tempering is the process of heating your piece to a much lower heat (than what you hardened it at), the tempering process takes the brittleness out and puts toughness into your work piece. If you are not satisfied with your Heat Treat Results, you can start over, from the beginning. Annealing, Hardening and Tempering. It is VERY IMPORTANT to Temper you work piece as soon after Hardening as possible. Some Steels will not Harden.

There are no Heat Treat Police!! If you use the incorrect Quench medium, your work piece may crack. If it cracks, you can throw it away and start from the beginning. Take a small piece of your work material and use it to test what Heat Treat Process works. Some Steels harden better in different types of Quench. Air Hardening, Brine Hardening, Water Hardening, Oil Hardening (the list of possibilities is too long, to post here). There are many types of Quenching Oil, there are many types of Steel, there are many different ways to Temper your work piece.

Some of the best Steel comes from Sweden!! Some of the most knowledgeable Steel workers, also are in Sweden. There are some of the finest Axes, made is Sweden. Talk to any business that works with Steel, they will help you to understand.

I also have many family members in Sweden. I have a very close friend who is working with the Axe Makers in Sweden. There is a group of Axe Makers, from all over Europe, that get together. There are many places to find knowledge, in Sweden.

Good Luck, Neil Gustavvsson

[Frosty]

11 hours ago, jimmyw said:

Terms are really crashing between english and swedish and even more as I don't understand the terms, or rather how to use the different techniques. I can't seem to find just clear information like a step-by-step how to actually harden/temper any piece.

Welcome aboard, glad to have you. You have two challenges to overcome here. First is the language differences but we can get through that, we do it pretty often so work with us and it'll be okay.

The other challenge being you frankly don't know enough to ask good questions or understand the answers. You can't help but misuse terms because you don't know which ones to use and we can answer you over and over but if you do't understand what we're saying then you aren't GETTING the answers. Make sense?

I'm not being mean I'd like to help you but I don't know if I can. There is NO simple set of directions to do what you want, heat treating isn't a simple process and it's different for different types of steel. Just because you start with a hammer doesn't tell you or anybody what kind of steel it is or what heat treatment it needs to do what you wish. 

Does that make sense? 

If you'll be patient and work with us we'll get things worked out with you. Okay?

Frosty The Lucky.

[jimmyw]

Thank you both for the welcoming.

Alright so I misunderstood the whole normalizing from the start, but I think I'm getting it better now. At first I thought I had to normalize the the old hammer head because it was hardened before, but now I understand I don't have to do that. 

As I think I understand now, as soon you warm up a hardened piece the hardening gets destroyed and I have to re-do the heat treatment again. 

I talked to a blacksmith here in Sweden he recommended I start with 1045 or 1672 steel for my hammers which both could be quenched in water. I'm gonna grab myself some pieces of 40x40mm stock of both tomorrow at the junk yard and some more stock, like 25mm 1045 to make a drift as well.

I'm very excited to improve becoming a blacksmith. I've always admired the work from a distance, since I've lived most my life in apartments. So I never really had the opportunity to try before now, when I bought a house with my girlfriend.

Thank you all for the help.

[pnut]

Remember to update us on the results and welcome aboard. Be safe and remember it's supposed to be fun. 

Pnut

[ThomasPowers]

Try to get your girlfriend interested in smithing---then you can help each other out on your separate projects or work together to make things for the house!  (There are a lot of times when having an extra pair of hands can cut down the time needed to less than 1/4 of trying to do it on your own.)

One of the "requirements" to be a curmudgeon here is being willing to answer the same questions over and over and over again.  A lot of us had to learn on our own; back when even finding books on smithing was hard, pre-internet, and so helping new folks not go through all the trial and error we had to do is "paying it forward".  Besides which the faster you get up to speed the faster you can go on to make new and unusual mistakes that you can report and WE can learn from!  None of us will live long enough to make all possible mistakes on our own!

[anvil]

Thomas, you are right on with all your posts on this thread. Great and clear advice!