Blade bites it..again..

[RainsFire]

so, I've taken two swings at making a katana blade, one out of 1050 steel, and one out of a car coil spring.. which I've heard is something like 1060..

the first one I made to thin, and hit one to many times after the heat treat so it snapped in two about mid length.. I just assumed this was my fault.. which it probably was.

The second one, I made as perfect as is humanly possible for using a coil spring, 28in blade length, hammered close to perfect shape, ground and sen'd to final shape, and clay coated with a really thick coat on the spine, and a fine coat on the bit.. did every thing the best to my ability following the "craft of the japanese sword" descriptions and images. I even normalized it 2-3times by bringing it to light oarnge heat and letting it sit in my cooling gas forge. (very slow cool)

anyway, my steel still had a gentle curve to the left with the spine facing down, so I stuck one end in the hardie hole to gently bend it back after the quench. needless to say it snapped.. I was kinda xxxxxx but not especially.. theres a point when you've worked on something for so long that when it breaks its like it doesn't matter.. but then I had a wakisashi, then a tanto, then a pocket knife..
now I have some prime damascus highcarbon steel billets.. I suppose I could take the 1050 from one blade, and the 1060ish stuff from the other and make a damascus katana..

anyway, at the end of this terribly long post... I would really like some suggestions.. cuzz I dont want to waste hours of work again.

I think the steel I used was an oil quench steel.. because that really shouldn't of happened, It wasn't even heated to the de-magnetization point and it fractures all over.

yep, so thats my vent..

[GVR-4579]

Wish i could help more, all i know is they use a damascas that is hard-soft-hard so the center keeps the blade from being too brittle, and the outside stays sharp. im not to the point of being able to weld or make damascas yet so i have no experience there.

[RainsFire]

ya, I had forgotten about that.. that might be a little bit responsible, but I still dont think a sword should snap in half that easily.. I was literally lightly tapping the spine of the blade on my anvil horn breaking it into 2in sections..

[brucegodlesky]

How many tempering cycles and at what temperatuere??

[RainsFire]

It was at a light oarnge, and I normalized it 3times by laying it in my firebrick annealing bed.
I heated it to a final heat of just under loss of magnetization, after clay coating with satanite with an almost 1/8th inch thick coat on the spine, and quenched it in a cool waterbath.

[Sam Salvati]

How long did you TEMPER it after the hardening?

[RainsFire]

I didn't.. which is probably a big part of what went wrong.. but I still don't think that was all of it. I literally tapped, like you would to lightly beat in a brad, the blade on the horn of my anvil and it shattered.. I have a good 6-8 2-4in peices..
Plus I polished up a few of these peices to see if I actually got a hamon, and found it to be cracked in many places.. (ending at the ashi so something worked..)

also, I thought tempering wasn't necessary because of the hamon?

[Ian]

If I were you I'd PM a gent called JPH who posts on here with your question, he's also known as Jim Hrisoulas, author of a few books on making sharp pointy things. As to my own two cents it 'may' be possible that the coil spring was full of microscopic cracks to begin with, especially if it was a used spring. Thats one of the pitfalls of using junkyard steel, no way to really tell unless you have a big microscope or a friendly metallurgist with a lab on hand. As to the first blade I really don't know, others with more know how will have to offer up their own two cents for you mate.

[pete46]

Forge Thick Grind Thin ?:confused:

[sandpile]

Rainsfire-- You have been starting right but getting off base for the finish.

Normalizing for a knife maker is taking it just to non-mag and dropping all the color out and most of the heat---then do it again, The last heat is the sure nuff normalizing according to the metal people. Set the blade in a holder of some kind that is not such a heat sink(alu.) letting the blade take its time to cool in still air. Straightening right after heat on each normalizing and it should stay straight through your hardening.

The time to straighten is while you are hardening the blade after a interrupted quench you have a short period of time to straigthen the blade. Once it gets below say 600 degrees you better be careful. Never --ever put a cool blade on the horn and hit it. Until you temper a blade it is as fragile as glass-=---sometimes it will sit on a cold table and break by its self. Temper just as soon as you have straightened it. Take it to a bronze or a light blue. Try a file on it if it is still too hard put a little higher temper(draw) on it.

Hope this is what you wanted..

Chuck Bennett

[Sam Salvati]

I didn't.. which is probably a big part of what went wrong.. but I still don't think that was all of it. I literally tapped, like you would to lightly beat in a brad, the blade on the horn of my anvil and it shattered.. I have a good 6-8 2-4in peices..
Plus I polished up a few of these peices to see if I actually got a hamon, and found it to be cracked in many places.. (ending at the ashi so something worked..)

also, I thought tempering wasn't necessary because of the hamon?

OH ..............*slaps forehead. WHoever said you don;t need to temper? The hard steel along the edge is still HARD STEEL. But it also sounds like there was cracks all over it before you even hit it, which means DON"T USE WATER. You can get some amazing hamons in oil try that next time/.

[RainsFire]

I think you guy's hit it on the head, I need to temper, I need to normalize more, and I need to quench in oil.

my 3rd attempt will work I feel lol.. It may be a wakizashi, but it'll be folded steel, and won't snap in half..

How high a carbon content do you want for the jacket steel? would my 1060 shattered blade damascus work? lol.. maybe I end up with a wootz steel look..

[cdent]

I've never tried a sword, but of the things you've tried, I'd consider going back to the 1050 and sticking with it for a bit. My tendency would be to try and minimize the variables and try not to be discouraged by the set backs.

Best of luck, Craig

[Rich Hale]

I think you would benefit a lot if you would go back to basics,,,I just seems to me to put so much hard work in a blade and not be real sure of the heat treat is not a productive way to work try and tip the scales in your favor forge some simple shaes of blades from whatever kind of high carbon steel you wish. harden and temper them and the try a bend test in a vise with proper protection a blade shoul bed and return to center,,,not stay bent and not snap,,then grind an edge on it and sharpen and try cutting cardboard with it,,,If that still gives you fits then why take the time to make a great looking blade and have another failure?

[RainsFire]

right, thanks you guys..

Apprentice man, I was being a little sarcastic.. I am making damascus out of the shattered blade, but It'll just be an experiment..
and I know what wootz is.. I just couldn't think of anything more witty and clever to say..

anyway, I thought if you quenched in oil you could get an opposite curve..thats one of the main reasons I've been sticking with water..
Also, is it possible to over heat the blade making the entire blade turn to the same kind of steel structure?
Is it neccessary that I use an interrupted quench to make a hamon?
also, where is a good supplier of 1060/1050 steel? online would be dandy..

thanks guys.

[Mike Turner]

On your shattered blade i would just toss that it is only going to cause you problems. I have not done any swords but have helped a friend do some heat treat on some Tantos. These were clay coated and from what I understand it is the difference in cooling rates from the spine and edge that causes the blade to curve not the quench medium. Some of the best makers I know get crazy hamons quenching in oil. I would suggest starting with some smaller blades and do lots of reading JPH has 3 of the best books I have read on the subject if you don't have them get them he has a link I think on his website. I also hope to be reading book #4 when he gets it finished. Here is a link to JPH's website Salamander Armoury. If I was you I would start with a knife get the idea of the steps involved otherwise you will just continue to waste steel and more important your time.

[ThomasPowers]

Coil spring is usually 5160 NOT "something like 1060". If you do not know the difference you are probably not ready for bladesmithing. There is a reason that bladesmithing is generally considered the pinnacle of blacksmithing, *lots* more stuff to know and juggle while forging and heat treating a blade.

It's much more deep hardening than 1060 so you may have through hardened it even with a clay cover. Then you take a brittle as glass blade and flex it at all and you are wondering at it breaking? Did you check the hardness on the edge and spine to see if they did differ?

It may have also micro cracked during the quench; how good was your temperature control before you quenched it? How thick was the edge? No coarse scratches on the metal before quenching?

Light orange sounds way too hot for that process and alloy---but you didn't mention what colourit was when you quenched it...The clay hardening process is generally done at a pretty low hardening temp. It's really based on a quite shallow hardening steel with a pretty low carbon content.

Tempering would have helped a lot if it was not already microcracked, this is not the steel that japanese swordsmiths worked out their heat treat for where they didn't temper after quenching. (well most schools, there were a few who tempered as a secret process step...) Car spring is an excellent alloy for sword blades being able to be hardened and tempered tough and springy; but it is not generally an alloy you try differential hardening with.

As for not wasting time, I'd say you have already shown a willingness to do so by not doing your homework first! A hard lesson and why I teach people to start with knives so their mistakes don't waste so much time and effort, cause you are going to make them!

A professional blademaker once told me to expect to throw away your weight in failures before you get *good*; sure wish I had done all of them when I younger and weighed a lot less...I had a piece of 100+ year old buggy spring for a late 19th century bowie knife fail in quench recently. As it did not work well in warm vegetable oil---too soft and shattered in warm water I'm going to shell out the money for some commercial fast quenching oil and try again

[ThomasPowers]

So your third blade is going to be "folded" would this be your first try at billet making then?

if so queue the "paying the dues" blues...and start with a tanto, please!

[Conan_568]

Quench in oil if you're not doing it already.
These traditionally made Japanese swords are quenched in water, but they're made from tamahagane laminated any number of ways.
I've read that the authentic Katanas are not all that hard and that the edge down quench causes compression in the edge.
The edge down quench is what curves the blade as well.
I quenched a Bowie that way once, it was straight when it went in the oil, but when it came out it had a nice curve to it.
Chuck is right, if you check your blade after you quench it you can straighten it.
I usually pull my blades out when the flames go out and have a look.

[RainsFire]

thankyou thomas Powers, I believe that is my problem.. I read somewhere that coil spring steel was generally 1060 or 5160.. so I guess it was 5160 then..

as to the bending a brittle as glass blade, I KNEW it was super hard, and brittle.. but isn't there a period of time where you can straighten a blade directly after an interrupted quench? thats what I was doing.. not being a dumb #%$ and bending cold steel.. so I think it was fractured..

no, no coarse scratches.. and I left it 1/8th inch thick on the thinnest point.

I've tinked around with making knives and tools for a few years, and I know its involved, but I have so totally done my homework its unbelievable.. I guess its just that I am cheap, and don't want to spring for a bar of 1060.. certainly not for these practice blades.. but If I make a good one, I will obviously do it right..

First attempt at making a billet, but not at forgewelding with coal, I've pretty much got it down.. should be a cool experiement anyway..

Im a kid, and have a bit of time to blow.. so I'm really in the experimental stage, plus im trying to enjoy it ..

whats the point of doing something for my own enjoyment if I don't enjoy it? Honestly, this is strange and all.. but I didn't really mind a whole lot breaking something as strong as steel into 2inch peices with my bare hands..

any way, wheres a good source for 1060 steel stock? online would be dandy..

[kbaknife]

It was at a light oarnge, and I normalized it 3times by laying it in my firebrick annealing bed.
I heated it to a final heat of just under loss of magnetization, after clay coating with satanite with an almost 1/8th inch thick coat on the spine, and quenched it in a cool waterbath.

I would say to lose the water quench and switch to a water-speed oil like Parks #50, and you will eliminate the shock that can occur with water quenching, but the fast oil still results in the same hardness as brine.
Which makes me wonder if you were using water, or brine?
Also, the key here is the SPEED of the oil!
I saw mentioned here in this thread numerous times about quenching in "oil".
What OIL?
What makes all the difference is the oil SPEED that matches the alloy of the steel. If you don't know the steel you're working with, how can you choose the quench media?
Don't use "salvaged peanut oil mixed with 30 weight........."!
Use industry standard quenching oil designed to properly remove heat from STEEL.
Not cook french fries.
Probably the two most important things you can do here is
1) work with a known steel.
2) Use the proper quench media.

[julian]

It sounds like you missed the period of time right after the quench where you can straighten the blade.

My advice would be get your heat treat down pat before moving any further. Long blades like swords are very unforgiving when it comes to heat treat flaws due to there being so much steel to get the same hardness/flexibility; it will take some practice.

[RainsFire]

ya, I think it was a combination of a bunch of things.. next time around I'll try and nock off more variables..

1065 is a decent steel for a katana with hamon right? I might do one strictly for cutting out of 5160, but I really want a crisp hamon..
its water quench too right? or should I still spring for an oil quenchant?

[sandpile]

RAINS FIRE- After reading through some your posts. I think if I was in your shoes(we all were once)I would buy enough of one metal say 1084 or go to the spring shop and get a BUNCH of 5160 drops.

Learn how to work this one steel. You need to study up on the one steel until YOU are comfortable with the one steel and have a good working knowledge of it. How it reacts under different heat ranges and how it quenchs. You can get a Hamon from 1084 pretty easy. You can differentially(sp)harden with a torch or clay it with an interrupted quenching oil like texaco or mineral oil.. Get Mr. JIM's books or ED Fowler's books either would be a great help You could go to BOB ENGRATH's web site. Lots of good stuff in there and written where you can grasp it.

Chuck

[RainsFire]

cool, thanks.. I think I might buy alot of 1065, or like ya said 5160 spring drops.
I just got a successful temper line on a small kitchen knife out of 1050 with ashi. It came out better than I thought, but I still need to polish it like mad..
I'm at 400grit..