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Matthew Marolt

Destruction

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So my kith originally started as a five layer billet of 52100 and 1095, weighing around 2.5 to 3 pounds if i was to guess. Welded the layers together and drew it out to show five straight layers of steel. got the blade somewhat shaped. So far so good. BUT, after allowing it to cool I discovered a crack. Tried to seal it up but it wouldn't take. Took it to the grinder to see how deep it was. Nearly through the whole thinkness of the spine. So there went the first blade. :/

 

After my first failure I decided to start essentially the same blade but a bit smaller and straight 1095. Forged it completely out. This blade hardly touched the grinder at all. It was all forge work. Which would be my first blade to fully forge the profile and bevels. (what would have been my fourth knife) I was very proud of it! I normalized it twice thinking it would be enough. But I guess not. The blade slightly warped and bent during heat treat. I fully tempered the blade to a straw brown. After I tempered it I got out the torch and tried to straighten it up. So reading in the complete blade smith it says to place the blade in a vise with the "kink" sticking out about an inch or so. Using the torch heat a small section of the spine to the straw brown range and torque it in straight. Well I did as I read and ended up with about 2 inches of the tip in my tongs and the rest of the blade firmly in the vise. Obviously too much torque even though I felt I was being pretty gentle with it. The grain actually looks okay to my untrained eyes.

 

Needless to say...I'm bowing down from the kith as I have no third backup and the deadline is tomorrow. :(

 

I'll post pictures tomorrow. As I'm too tired and bummed to do so tonight.

Maybe one of you guys can help me out with what went wrong?

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With the 1095...the normalizing you did may very well have been sufficient. You can normalize 3 times even and still have significant warpage.

 

When you quenched, (I'm assuming you quenched in oil. In my experience water quenching 1095 is very hard to do without cracking the blade.) did you agitate the blade? In my experience, that's been the most imporant factor in reducing warpage. You've got to move the blade back and forth along the axis you'd measure the width of the blade along (i.e. up and down or towards the spine then towards the blade, but not side to side), if that makes sense. You don't have to agitate with a very large amplitude, just 2-3 inches of constant movement during the quench will suffice.

 

As for straightening while tempering, I think what Jim meant in his book (I might be wrong here, and Jim might be able to correct me here) is to use that method for kinks that were closer to the center of the blade, not near the tip. Bending only the tip will usually break the blade before it fixes the bend, as you almost always bend too fast/hard when using tongs and a vice. A more controlled method is to put shims in your vice and bend the blade past straight in the other direction of the warpage using those shime (three of them, to be exact), after heating the spine with a torch. This way you can adjust pressure very slowly using the screw on your vice.

 

The way I fix warpage is to bend the blade over a wood dowel or similar object. I put on big thick heat-resistant gloves (firefighter's gloves, actually) so that I can touch the blade while it's hot from tempering, then press the bend back to straight over the wood dowel. This way, I can slowly apply my body weight to the blade, slowly increasing pressure until I feel I've fixed the warpage. Then I look at it again and repeat with very slightly more pressure if the warpage wasn't fixed. Sometimes it takes me 3-4 times of doing this, and every time you must be careful not to let the heat bleed to the edge. I think the key is to just take it as slow as possible. Any fast motions will frighten the grain structure, and steel breaks down very quickly when it gets scared :P .

 

Also, you really need to apply force evenly across the entire blade. This means using leather or a soft wood (both will burn, so they must be relatively expendable) between whatever you use to apply bending force and the blade. Soft things squish and distribute the force more evenly, reducing the chance of breakage.

 

Anyway, it is also helpful to practice warp straightening on scrap blades. I find it's the hardest and most nerve-wracking thing I do while making a blade, but I got way better after doing it about 10 times on practice blades.

 

Good luck, and sad to hear you won't be able to make it on this KITH.

 

-Dan

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Thanks Dan! that's a great bit of advice! I did not agitate it at all. just a straight quench in transmission fluid. I've done the same with smaller 1095 blades and it seemed to work well.

 

anyway, here are the pictures i promised

 

2012-03-01154443.jpg

 

2012-03-01154501.jpg

 

2012-03-01154524.jpg

 

2012-03-01155301.jpg

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I agree with troy, it looks big enough that you might be able to grind a new tip on it!

 

Also, in you picture, it looks sort of discolored towards the spine, could this have been a small crack you did not see. if so, that may have contributed to the break.

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I dont believe there was any crack there. It did however crack right on a notch I filed on the spine. I think the discoloration was from me using the torch on the spine. I heated it to about that color then tried to torque it in straight. I believe thats what its from but, I could be wrong.

I never saw a crack though

 

I am going to salvage the blade. Just wont be done for the kith :(

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garrett its just the pictures. My crapy phone cant take great pictures. The grain looks pretty fine but I do agree it could be a bit smaller

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Matthew... I was just reading through all the KITH threads and saw this. That grain is huge. Fine grain in a normalized blade is like silk pie. I wish I had some pictures to show you...

 

I would look closely for any other cracks around that broken spot, reshape and do further normalizing cycles.. one or two at subcritical. The blade is salvageable... but you sure need to do some grain refinement.

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