New Twist---RR Spike Style

[tippit]

I just got done reading that RR spike post.  I've always liked the look of RR spike knives but it's too much work (for me anyway) to end up with a lower quality blade edge. So I decided to see if I could do a RR spike look-a-like but with good high carbon steel.

Quest: 5160 round stock squared off to twist the handle and then to flatten the blade.  This was as much a project to help me get used to using my power hammer plus trying something different.

The handle was twisted then reverse twisted at the butt just for a different look.  Blade quenched fine with no warping even though I took the edge to finish.  Edge tested in the 60 range Rockwell as both old or new files skated without grabbing/digging in.  Blade is in the oven tempering now.  Nice thing about this one is I Don't even have to put para-cord handle on it        Doc

   

   

   

   

   

[kbaknife]

That's pretty cool looking and good exercise as well - at least for your power hammer!
Jeff, you'll come to find that warpage has far less to do with how thin your material is, or how many times you did or didn't thermal cycle, than it does to how equally and evenly your blade is shaped.
As well, blades that do NOT! get a lot of martensite created don't warp either!
(That's the first "red flag" that should go up when you hear someone say they never get warping! It's because they are probably NOT! making any martensite!)
The martensite "crystal" has a different size than the other grains in the steel - larger, actually.
So, if you shaped you blade unevenly and have more mass on one side of center than you do the other side of center, that side with the most mass wins!
It'll push your blade edge the other way.
Maybe you could make those knives and sell them to Gandy Dancers.

[tippit]

Karl,
Gandy Dancer...You got me there Karl!  I was almost afraid to Google Gandy Dancers    Jeff

[tippit]

RR spike impersonator finished.  I cut the tail off, polished blade, and put a convex edge on.  Color of blade is due to sun near sunset...kinda cool!  It feels real nice in the hand with the weight of the twisted handle.  I'll definitely do this again.  Maybe try and find some Gandy Dancers         Doc


   

   

   

   

[STILL-HUNTIN]

Prety cool little knife. It looks awkwardly heavy on the twisted end? Does it balance? Very cool looking!!! I like it!!!

[kbaknife]

Originally posted by tippit:
Karl,
Gandy Dancer...You got me there Karl!  I was almost afraid to Google Gandy Dancers     Jeff

I used to work on the railroad in 73-74. That term just always stuck with me.
Hey, I will amend my post above to say that one will also not get much warp if he is only edge quenching either - or only austenizing the cutting edge with a torch and quenching just the bottom portion.
There's a lot of ways to avoid warping, but the most important way - if you are seeking a lot of martensite - is even grinding.

[tippit]

Karl,
I do edge quench plus my grinds are near finished to 400 grit when I quench.  I also normalise even while forging by going cooler & cooler as I get near finished.  Then normalise at and below non-magnetic 3-4 times before quenching.  My broken test blades have helped me immensely to see the texture inside the blade.  

Thanks for the helping info from the likes of you, Lin, Doug and others here    

Now I have a Question:

I learned from a couple instructors at ABS symposiums that when you quench there is a short period of time right after the quench with the blade still HOT...That you can actually straighten a curve spine that may develop at quench by straightening by hand!  I have done this a couple of time with nice success.  You can not straighten a warped grind but you can straighten a curved spine.  Can you elaborate?  Thanks

Still-Huntin,
It actually balnces quite well.  The weight in the handle makes it feel very solid...Doc

[kbaknife]

Sure - it's just that once you get the steel down below 900 in the required time, hold the blade in the oil for about a count of 8-9-10 and pull the blade out.
If you get a lot of smoke - but no flame - you should be around 400 degrees.
If it dries out really quickly you are probably too hot.
If it stays wet - but no smoke - then you waited too long.
Anyway, the creation of martensite takes time. It doesn't happen immediately.
You've got to get down below 400 for the creation of martensite to begin, but you've got yourself out of the pearlite range by getting down below 900 degrees in the required time.
In this little window of opportunity - around 400 degrees - the steel is amazingly malleable.
Pull it out of the oil and give it a look. I have a hard time with it because of all the smoke! But if there is an obvious bend in the blade, you can almost bend it with bare hands! Not really bare, but with welding gloves on because it's 400 degrees - right?
It is so easy to bend that it's not difficult to bend it too far the other way! I've done that on more than one occasion.
Let me know if any of that makes sense.

[Scott Roush]

very cool...

[tippit]

I know that I can do it and I always check to see if needed...but now I know why!  Karl...thanks once again.

[Steve Nuckels]

I do like your style!  Great creation!

Steve
-------
Potomac Forge

[JMR]

Great looking knife! I love the twists and was hoping to turn my spikes into something like that after a lot of practice.

[kbaknife]

I did forget to say that once you have done your checking and fixing, and don't waste any time, you need to get your blade right back in the oil to cool.
This also helps to gradually even out the heat reduction in the blade, in addition to checking for warps, this way the different thicknesses of steel cool down at the same rate.
You may have heard the term "interrupted quench" before.
I do it whether I'm looking for warps or not.
But I'll bet you knew that.

[tippit]

Karl,
You would have lost some money on that bet     But I understand the process a lot better now. Jim Babson went over this a couple of times but it seems like I didn't have all the pieces of the puzzle.

[toppredator]

very cool...never seen one like that