Does anyone here ever get perfectly straight knife blades?

[webradbury]

I have made several knives so far, and none have been absolutely straight, nor noticeably warped. The most recent, I am very happy with, even though the blade is not perfect. It's hard to tell, but if I sight down the blade holding several different ways, I can make out a little warp. It's really hard to see unless you hold it just right.  Happened during the quench. I tweeker it gently after quenching and thought I got it out but saw it again after tempering. Am I being too much of a perfectionist? Does a tiny bit of catiwompus add character and set a handmade knife apart from mass produced cookie cutter store bought knives. I will always strive for perfect in my work, but I don't intend to scrap a very nice functional blade due to an imperfection. What say ye, gentlemen?

I have to finish the handle and pommel tomorrow and I will post pics.

[B.Barker]

Some times the way a blade gets filed can cause it to look warped but it was actually done when filed or ground not when quenched. Yes blades do come out straight after heat treating when everything is done right. It takes experience though. Don't get discouraged though, as the saying goes Rome wasn't built in a day and neither are good knife makers. Back when I made more knifes I got pretty good at it. Lately it seems three out of five blades get a little warp. But I've not been blade making for a few years. You can straighten them out when drawing the blade in an oven. Wick Elerby wrote how to do it in a post a year or two back. 

[tippit]

What steel are you using and what are you quenching it in?  Are you forging or stock removal?

My blades are ground straight before I quench...but I've been doing it for over twelve years.  I use Parks 50 which is a very fast quench and mostly work with 1084, 5160, and 5210 occasionally files and springs.  If your grind is uneven, then your blade will probably warp at quench.  Even straight blades can warp at quench, but you can straighten some warp by hand at quench.  I will quench for the count of 10 then pull the blade out handling it with welder gloves.  You can take out most warps just by straighten/bending with your gloved hands or light taps on the anvil.  Then throw it back into the quench.  You have probably a couple of minutes before the crystalline structure of the steel changes and is still malleable before hardening.  If my blade comes out with a warp, I throw it back in the forge and re-quench.  You need to try to straighten at quench not at tempering because that's when the steel hasn't hardened yet...the change in crystalline structure is called the Perlite Nose Curve.

If you are forging and just starting, I'd recommend taking a weekend Hammer-In Course from the  American Bladesmith Society (ABS)...you will cut years off your learning experience.

tippit

[webradbury]

It's 1084 steel. I forge it out then finish grind. I normalized twice and quenched in 130 degree canola oil. Used a jet treat oven so I know the temps were correct. Oh, well. Practice does make perfect

[tippit]

webradbury,
When you quench, pull it out of the quench after 10 seconds with gloves and a wad of paper towels to wipe off the canola oil.  You will be surprised how much you can blend the blade by hand to straighten it or very light hammer taps on the anvil.  It doesn't take much pressure as you can over do it.  Then stick it back into your oil.  The nice thing about 1084 is you have time to straighten it.  1095 hardens much faster, giving you less time to straighten.  If you get serious about forging, try to find some Parks 50 quench oil or the equivalent.

I forge to almost finish before I quench giving me very little room to grind out a warp after quench.  I always check my straightness that way.

Where do you live?  If there are any ABS smiths in your area, I'm sure they would help you.  I am a moderator on Trad Gang in the Hunting Knives and Crafters forum.  We have some amazing Master and Journeyman smiths that will answer any question.  I've had Mastersmiths and Hall of Famer Smiths take me into their shops and show me everything they do.  No petty secrets with bladesmiths.  That's the nice thing about this site too.

Good Luck...tippit

[tippit]

One more bit of advise...don't throw away any of your knives that you don't like.  Throw them in a bucket and as you get better re-grind them.  You will be surprised by what you can learn.

[webradbury]

I cut myself with this blade already so we have a blood bond. Up to now, the first thing my knives cut is me! I'm clumsy and have big hands.

[tippit]

Welcome to the Bond   Twelve years ago I bought a caper for hunting.  I told the maker how much I liked it. I also told him I make most of my hunting gear and wanted to make my own knife.  We have horses and our farrier gave me an anvil and old gas forge.  He then taught me over the internet how to forge a knife.  He is the ranch manager of Brokaw's Montana ranch.  It turned into a great friendship.  We bowhunt and fly fish together in Montana, on my  South Carolina farm, and my hog lease in south Georgia.

Knife making has it's perks!

[LRB]

  The safest method of straightening a warp is after at least one temper cycle. The blade is clamped to a straight thick piece of steel with a small wedge insert between the steel and the blade at the area of apex, causing a slight degree of over straight in the blade. A penny is used by many for this wedge. Then do another temper cycle. Repeat if necessary. Repeated tempers make no changes to the tempered hardness as long as they are all done at the same temp. Some steels such as 01 can be hand pressure straightened for as long as a 5 or so minute window after quench. Beware doing this hand straightening the first time. With 01 it is easy to over straighten during the first couple of minutes.

[Ky-Flinter]

LRB,

Good to see you back!

-Ron