Jump to content

Flint and steel, made out of spring steel


Recommended Posts

Hello to everyone!

 

My last project was the steel for a flint and steel tool. 

The steel used for it was coil spring that I got from my mechanic. The design was the same as the one my sister has. After forging it out I quenched it at a non-magnetic dull red in canola oil. After sanding of the oxides I tried it out... couldn't get any sparks. While sanding it sparked a lot, maybe the hardening process didn't work? Because when I used the flint on it, after a few tries, there where some scratches.

Has any one of you got any hints?

 

Greetings from Italy

Alex

1652293044976233340647348197759.jpg

Link to post
Share on other sites

Might try it hotter for the quench. Grain growth wouldn't be an issue as it would with a blade.

 

Make sure your steel is cleaned to bright before you quench, and the clean it again after hardening.

 

The coil spring could be in the 5160 family and a water quench might crack it.

 

I use old files with a water quench and then suspend them in boiling water for about an hour to (possibly) temper them a little bit. Maybe I just imagine the boiling helps.

 

And also, I do normalize them like a blade before I harden... heat to critical, cool to black, heat to critical, cool to black, then clean it up and quench it.

Link to post
Share on other sites

If it is 5160, you didn't get it hot enough.  It must be at least 38 degrees C (100 F) hotter than nonmagnetic, or a bright red in low light.  Grain growth is actually a good thing with fire steels, as the larger grains make bigger sparks.  

 

As Don said, old files are a better choice for this application.  You want as much carbon as you can get, within reason.  

 

You did a great job on the forging, though!  Looks good. 

Link to post
Share on other sites
6 minutes ago, Don Abbott said:

Might try it hotter for the quench. Grain growth wouldn't be an issue as it would with a blade.

 

Make sure your steel is cleaned to bright before you quench, and the clean it again after hardening.

 

The coil spring could be in the 5160 family and a water quench might crack it.

 

I use old files with a water quench and then suspend them in boiling water for about an hour to (possibly) temper them a little bit. Maybe I just imagine the boiling helps.

 

And also, I do normalize them like a blade before I harden... heat to critical, cool to black, heat to critical, cool to black, then clean it up and quench it.

Okay I'll try to quench it again with the cleaned surface, but should the oil be hot or is it okay if it's room temperature?

1 minute ago, Alan Longmire said:

If it is 5160, you didn't get it hot enough.  It must be at least 38 degrees C (100 F) hotter than nonmagnetic, or a bright red in low light.  Grain growth is actually a good thing with fire steels, as the larger grains make bigger sparks.  

 

As Don said, old files are a better choice for this application.  You want as much carbon as you can get, within reason.  

 

You did a great job on the forging, though!  Looks good. 

Okay thank you, I'll keep that in mind.

And thank you for the compliment!

Link to post
Share on other sites

Okay so I tried it again but it still didn't work, I got the oil at about 50°C, the steel was at orange and I quenched it until it was cold, steering it around in the oil. It don't get it. And as a beginner I'm not even sure if its really hardened, I tried the file test and it sounds like it's hardened, but still I feel like it's not. Is there any other way to check if it's hardened apart hammering it in the vice until it breaks or bends?

Link to post
Share on other sites

If a file skates off it, that tells you it's hard.  For a real test, as you said, put it in a vice and give it a smack and see if it breaks.  I have to say, 5160 (coil spring) is not my favorite material for strikers.  Old files, crow bars, and old tire irons (not the chromed ones, nice old rusty ones) are better.  Water quenched 1095 always works for me.

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

Link to post
Share on other sites

Greetings Alex,

 

Listen to the metallurgists on the forum, I'm not one of them.      But, I seem to recall reading something about chromium in steels like 5160 negatively affecting fire striker performance.   I could be wrong.  But as everyone has said, a different steel may be a better choice for this project.    Something simpler in the 1070+  range, perhaps?   But if you wish to keep trying this particular piece,  maybe you can try and obscenely long soak time before the heat treat.  Maybe get it up near welding temp and hold it there for a while, maybe 5-15 minutes?   But that is also likely to cause a lot of decarb, which is not great for this application using 5160.   This might help increase the grain size.    Then maybe leave the striker surface a bit rougher, instead of so flat and polished.   Might give something more for the flint to bite on.   I mean the whole reason the thing works is because the flint is cutting off pieces of steel.  Maybe try a sharper piece of flint ?

 

Also, "coil spring from my mechanic", does not definitively mean that it's 5160.  Coil springs can be made from all sorts of stuff across different countries.  Like 9260 for one.  Which I'm not sure is a good material for a fire striker. 

 

I wonder if doing a blister steel kind of cook canister on a that material would make a difference?   But most likely not for the expense, time and effort, versus buying a small piece of the appropriate steel or just an old file.

 

As far as hardness testing.  The old file skate test to a good indicator.  Just be sure that you are not hitting scale when you are testing it, because that stuff is way hard, and could give you a false reading.  Also, if you are suffering from decarb, then on the contrary, a deeper grind might present some of the better high carbon material.  I'm not sure on how deep decarb can go.

 

If you got a good old knife you don't care about, that you know is good and hard, you can try using that knife to shave or cut into the fire striker.   If you can cut pieces off, or make and indentation with the knife onto the fire striker, then chances are the fire striker is not hard enough.   I believe strikers are supposed to be in the 60+ Rockwell range.  Again, could be wrong.

 

Good Luck

Edited by Bruno
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...