Lyman, any time we deform cold metal at all we introduce strain energy, strain energy does not necessarily have to be a problem if it is uniform, e.g. cold hammering all down one side of a bar and not the other will almost be certain to result in warpage. And with that last example we can also consider another major factor in the amount of strain. I often think about all of these things along with your same concerns whenever I straighten an annealed blade while it is cold, but I go ahead and do it anyhow. The small amount of strain to remove a slight curve is very minimal and widely distributed compared to other factors such as heavy grinding, or less than perfectly even heating.

I would handle it in one of a couple ways-

1. Straighten it cold and proceed as normal, interrupt the quench (at 450F for 5160) and see if there is any warpage. If there is, put the gloves on and push it straight before it cools.

2. If I was really concerned after straightening it cold, I would do a stress relieving heat treatment on the blade. This is not normalizing and only requires a quick heat to around 1200F (dark black/red)to annihilate any strain issues that could have been introduced. After this I would then proceed as usual. I recently did exactly this when I had a blade do something so odd that I just didn't trust the situation. I had a fully annealed blade trued up totally straight and flat according to a surface plate, but the next day found it had inexplicably warped for no reason at all as it sat overnight in the annealed state. This should not happen! This flustered me so much that after I re-straightened the blade it went straight into a 1200F kiln, just to be safe. The blade behaved itself completely after that but it definitely made me feel better to do the stress relief.

Normalizing really is not a stress relieving operation as much as it is for "normalizing" the internal structure of the steel, thus it is done at higher temperatures and results in affecting grain, more chance of decarb and scaling. Stress relieving, costs the steel very little surface carbon, practically no scale and leaves the internal structure exactly as you left it from the anneal, while it zaps any strain energy (stress) that could give you problems.

You could also only heat to a dull red and push it straight but your control over the operation will be less by not being able to just handle the blade.

In any case there are several very good options at your disposal without the headache of another normalization or anneal.

P.S. Thank you for your question, I really like this new forum, and it is nice to see participation here where we can help each other out. I think an online source for people to go to the ABS knowledge pool is going to be a really big benefit to the bladesmithing community and I find it very rewarding to participate.

Thanks Kevin

I'm going out there to have at it, I'll let ya know how it turns out <img src=' http://www.americanbladesmiths.com/ipboard/public/style_emoticons//biggrin.gi f' class='bbc_emoticon' alt=':D' />

So I went for it and straitened it cold in a vice with blocks of wood and it looked good to go it didn't look warped as it got hot but when it came out of the quench it has twice the bend that it had before. Not sure where I went wrong but the other 3 came out so I'm going to finish them up and then get back to this one

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So I went for it and straitened it cold in a vice with blocks of wood and it looked good to go it didn't look warped as it got hot but when it came out of the quench it has twice the bend that it had before. Not sure where I went wrong but the other 3 came out so I'm going to finish them up and then get back to this one

put the tip of the warped one in a vice and hold a soaking wet cloth against the edge while you heat the spine and body of the blade with a torch to turn it blue. Apply presure on the tang while it is hot and push it straight. The wet cloth will protect the edge and when the main part of the blade is hot it will move better. Above 350F the modulus of elasticity and brittle failure modes of the steel begin to get skewed out of whack and you can bend and move it without worrying about thigns that would happen if it were cold. You can also correct slight warps during your temper with simpler steels like 1080 and 1095.

The fact that it warped intitally as well as during the hardening says that there were some larger issues in the blade. You may want to adjsut your annealing cycle. How do you anneal your blades?