Help Needed!!

[D.J. Smith]

I was at work the other day and was thinking about building a knife so, I found a rail road spike and took a rose bud and hammer to it and beat the crap out of it until I got a shape I like. Now that I got it close to straight and shaped like I wanted, My question is, What's the best way to harden the blade???? Thanks

[kansas stik man]

well the spike is still hard so you need to soften it first by anealing, this is heating to non magnetic 'critical' temp.  after that either put it in ashes to cool slowly or if you have a fire that you used to heat it just leave it in the fire tell it dies out completly after that you can file and sand the blade to shape then you harden.  to harded you need to heat to non magnetic again then quench it in oil very quickly. after that the blade is very brittle so be very careful with it. you will need to sand off the oil on the steel.  after that it will need to be tempered , this can be done in your oven and the temp will very depending on steel type but a good place to start is 350*.  you will leave it in for two hours and then let cool in the oven.  then another cycle of two hours and let cool again.  after that you need to test the blade to see if its too hard, it will chip the blade.  if its to soft it will not hold an edge.  i know it sounds confusing but that process was taught to me and will help a great deal.  lots of guys on here with tons more experiance than me.  lin , karl, steve. they all have great advice to offer.

[Cody D Works]

good advice! It actually depends on the rr spike I believe. If it's a high carbon one you need to edge quench it. In water I think I read. As far as tempering after that you may want to test the edge before tempering. Everything I have read on rr spike knives is that they are cool and great to learn on but aren't practical as knives bc they don't hold an edge well. I have done a ton of reading on this hopefully gonna get my forge welded up tomorrow so I can get started myself.

check out the i-forge section on anvilfire.com it has a rr spike knife tutorial on there that may help.

[D.J. Smith]

Thanks for all the help, At what temp will the metal become non-magnetic and can I cover the blade in sand for anealing.

[kansas stik man]

the temp will depend on the type of steel it is but you can litterally heat the blade tell its glowing redish orange and try to stick a magnet on it. if it dont stick be fast and quench if it sticks then put it back in the fire. and no you can not use sand it has very little insulative properties.  simple wood ash is the best for insulation.  just put it after heating it and put it in the ashes for a day and forget about.

[D.J. Smith]

I got the steel soft, I can cut it with a file now. I have been shaping it today. I will try to get it harden this week at work. Thanks

[kbaknife]

I thought I might toss this is here for anyone who is interested, but for nearly all of the steels we work with, they ALL go non-magnetic at 1414 degrees.
It's the IRON in the steel that is going non-magnetic.
And the IRON is the same in all of the different steels.
We can only use non-magnetic as an indication that we are approaching our different austenizing temps for whatever steel we are working.

[Scott Roush]

rr spike blades make fine knives as long as they stamped HC. They just need to be sharpened more often.

I've quenched mine (whole blade) in brine and they do fine.  Just dissolve as much salt into your water as it will hold. I've never bothered tempering them. Why make them less hard? They don't get that hard anyway.  If you do temper I would maybe just do it the 300 range just for stress relief (and maybe taking care of retained austentite?) rather than drawing back too much hardness. They don't get brittle.. believe me. I've made quite a few rr spike tomahawks and I haven't tempered any of them.  I've yet to chip a blade chopping with em...

[D.J. Smith]

I dont know if it was stamed HC, I didn't look to tell you the truth. What temp. should I get the blade before quench in the brine??

[kbaknife]

That's good info, Scott.

If you have a good steady heat source, bring that blade up and as it starts getting brighter and brighter, check frequently with a magnet of some type.
Pay close attention to the color of the cutting portion of the blade and keep heating it until it goes to the NEXT color phase brighter than what it was at non-mag.
Do like Scott said and quench in brine - a mixture of water and enough salt to float a raw egg.
Temper like Scott said, he would know.
I've got a whole pile of brand new "HC" spikes.
(Hope the RR doesn't miss them!)

[D.J. Smith]

Thanks for all the info,
I work at a place where I can have all the fire bricks and nicholsen files I want. This weekend I will build me a propane forge. I like the looks of all the spike and file knives on here, I like the rustic look.