First knife Issue... Guidance needed.

G

Gottmituns78

Joined
Apr 28, 2012
Messages
125
Hello gentleman, my name is Matthew. After quite a few months of planning I finally dove into making my first knife. I read all of the threads and look lots of notes. (Literally a comp book of notes) I got ahead of myself and in grinding my bevels I forgot to keep the blade cool and I seemed to have hardened the tang. I was able to get dimples into the surface but I could not get my pin holes opened up. So I turned to my trusty comp book and decided to retemper the blade to soften it again. I built a fire and got myself plenty of coals and placed the blade into them.... Long story short I somehow managed to bend the blade. It is a pretty substantial bend. Which leads me to my question. How do I straighten it back out. I have worked my tail off on this monster and I am really proud of the work I have done. I really don't want to have to scrap it and start over. Over all it is 15" long, 1/4" thick 5160 with a full flat grind. I e reached out to a fellow forum member who is close in location, but I could really use all the advice that I can get.
 
Heat it up again a bend it back straight. Need to redo the HT but that is doable. What did you use to make the blade? You should not have hardened the blade while grinding. It was probably hard before you started. Can you re heat treat the blade?? If not someone might be able to help you out. Darren Sanders was doing a lot of HTing here. If you can't find someone or are unable to do it yourself, drop me a line. I might be able to help you out.
 
I notice that 5160 is particularly succeptable to work hardening and Just yesturday, I had the same thing happen. I went to drill the holes for the handle pins and they didn't want to drill, At that point I just toss it into the forge , or use a propane torch and heat it up, then stick it in a bucket of ashes to cool slowly.
 
Also, what kind of bits are you using? I had a bear of a time drilling some 15n20 recently, killed some bits and assumed it was work hardened. The right bits fixed everything.
 
Gottmituns78 said:
Hello gentleman, my name is Matthew. After quite a few months of planning I finally dove into making my first knife. I read all of the threads and look lots of notes. (Literally a comp book of notes) I got ahead of myself and in grinding my bevels I forgot to keep the blade cool and I seemed to have hardened the tang. I was able to get dimples into the surface but I could not get my pin holes opened up. So I turned to my trusty comp book and decided to retemper the blade to soften it again. I built a fire and got myself plenty of coals and placed the blade into them.... Long story short I somehow managed to bend the blade. It is a pretty substantial bend. Which leads me to my question. How do I straighten it back out. I have worked my tail off on this monster and I am really proud of the work I have done. I really don't want to have to scrap it and start over. Over all it is 15" long, 1/4" thick 5160 with a full flat grind. I e reached out to a fellow forum member who is close in location, but I could really use all the advice that I can get.
Click to expand...

I always try to influence the makers I teach to start with small knives. Once you have the steps down, you can move to larger knives without pitfalls knocking your feet out from under you. Small knives tend to warp less as well.

This is not an easy thing to fix. I would heat it to critical, and then cool it between two plates. That would straighten it. Then I'd soften it in vermiculite (critical, then into the vermiculite). Then Drill, then HT normally. Overheating it in a bed of coals could swell the grain and make it susceptible to breakage.

I stopped using 5160 because of PITA issues like this.
 
In the process of making this knife I have realized why it was so recammended for us to start with smaller blades. It is the one piece of advice that I intensionally ignored. I am a big kid, so I have always had a bit of an affliction for larger things. Particularly blades, the little ones just don't feel right. That being said, I've just been using Milwaukee bits that I buy from work. Mr. Richards I can heat it again, my problem is that I don't know how to straighten it once I have it heated back up. I started with a piece of 1/4" x 2"x 20" 5160 that my neighbor got from a a supply house here in louisville.
 
Once it is softened you can use anything to straighten it. Use a carpenters level for a flat surface to check for straightness and bend or pound or whatever you need to do to get it straight. Put it in a padded vice and bend it, use clamps and shims, almost anything will work, Once annealed it will bend back very easy, you are thinking its harder than it will actually be. Then make sure you normalize before heat treating or you may see that bend come back.
 
You must log in or register to reply here.
Back
Top