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Old 11-24-2017, 09:44 AM
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Default reheating metal

Hello all, pardon my ignorance. I'm making some fire strikers and know that the edges need to be brittle so that the metal gets shaved off when striking against a piece of flint. now, after I hardened it and need to make changes to the configuration of the striker, if I reheat it, will it make the striker more brittle? Thanks
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Old 11-24-2017, 11:03 AM
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If you heat it hot enough to bend or shape, you will have to quench it a 2nd time for it to still be hard.
Heat treat can be done over and over but it can't be done halfway. If you get it hot enough to soften it, it has to be quenched again.
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Old 11-24-2017, 03:03 PM
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And if you used regular A36 no amount of quenching will make it hard enough. Kasenit almost comes close, but the surface hardness wears off fast.
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Old 11-24-2017, 04:44 PM
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An iron/steel alloy with sufficient carbon has to be heated to a non-magnetic point so all the goodies go "into solution", or thereabouts. Sort of like dissolving sugar in hot water. Then it is quenched to solidify it quickly enough that there's some hard crystals that form during cooling, not just taffy. Then you "temper" to get a balance of hardness and toughness by eliminating the amount of the hard crystal structures.

It's a bit like making ice cream that isn't gritty or soupy. Let it soften up too much and you have to start the cycle again, not just throw it back in the freezer.
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Old 11-24-2017, 09:40 PM
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thanks everyone.
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Old 11-24-2017, 10:15 PM
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Biker555, I learned a bit from a 70 year old blacksmith in Thailand just by observing him. I couldn't speak the language worth a crap for the first couple years, and he spoke a different dialect anyway. I wish I'd had a clue about what he was doing at the time about hardening and tempering spring steel. But I did learn how to pump the "bellows" to his satisfaction so that the heat was right and no charcoal was wasted.
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Old 12-03-2017, 07:14 PM
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Biker555, I learned a bit from a 70 year old blacksmith in Thailand just by observing him. I couldn't speak the language worth a crap for the first couple years, and he spoke a different dialect anyway. I wish I'd had a clue about what he was doing at the time about hardening and tempering spring steel. But I did learn how to pump the "bellows" to his satisfaction so that the heat was right and no charcoal was wasted.
NICE..

you going to the ABANA conference in 2018.. Its down the road from you.. Dayville I believe..

I'll be going..

Old fashioned strikers were made from case hardened wrought iron.. As were most parts on flint lock rifles..

Today with steel being so cheap, the best fire starters would be as high a carbon content as possible..

Also there is some carbon loss with each heat, reheat cycle but for you intended purposes it won't harm anything..

Practice makes perfect..
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Old 12-04-2017, 09:45 AM
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Jenn, the ABANA conference will be at the Meadow Event Park north of Richmond near King's Dominion amusement park, June 27-30. Used to be a racehorse farm. "Secretariat" was raised there. It's about 35 miles north of me. They have the state fair there and gun shows and stuff. I used to take the kids shooting at my buddy's property just a mile or so beyond there.

It's definitely something I'd like to see. Keep me appraised of your plans and maybe we can meet up. I could give you a handful of Thai machetes.

Here's the type of "bellows" I used to operate. More like butter churns.
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Old 12-04-2017, 11:23 AM
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Originally Posted by USMCPOP View Post
Jenn, the ABANA conference will be at the Meadow Event Park north of Richmond near King's Dominion amusement park, June 27-30. Used to be a racehorse farm. "Secretariat" was raised there. It's about 35 miles north of me. They have the state fair there and gun shows and stuff. I used to take the kids shooting at my buddy's property just a mile or so beyond there.

It's definitely something I'd like to see. Keep me appraised of your plans and maybe we can meet up. I could give you a handful of Thai machetes.

Here's the type of "bellows" I used to operate. More like butter churns.
I certainly will keep you in the loop.. I'm going down for a week.. My Mom lives in Scottsville so will be staying with her.. I'll PM you my contact info when the time grows near..

I love them bellows.. Looks like an arm pumper workout..
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My attack thoughts are attacking my invulnerability.

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Another Johnson model J Project
Lathe? Maybe..... 1958 SBL 13"
Yeti Esseti Aka running welder on 3phase.
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Old 12-04-2017, 04:14 PM
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I bought my old Idealarc 250 welder near Scottsville a few years ago. I know the Scottsville library Branch Manager. My old high school sweetheart.

Those butter churn air pumps are easy to work. The pistons are a wooden disk on a piece of bamboo. Seals are chicken feathers glued around the perimeter with resin or natural shellac. Very little friction.
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