temper line fade

[Mike Byrd]

Hi world, this is my first foray into the realm of knifemakers.

Being a beginning knifemaker I have encoiuntered many problems. The most current is fading temper lines. My blades made of L6, 1075 and 1095 appear to harden o.k., using Wayne Goddards differential quench method and his goop recipe. Although, I used transmission fluid on the 1095 steel. They are then triple tempered between 325-375deg. When I etch them, using ferric chloride, the temper lines are well defined. As I sand and polish them the temper lines fade and disappear. I can't figure out what I am missing. Or am I failing in my hardening process? Any ideas or suggestions are appreciated. Anyone with info please e-mail me direct or post on the forum.

 

[Chiro75]

That's what'll happen. The etch is sort of a cheat for a temper line. If you polish the steel adequately, you'll see it on it's own without an etch. I'm trying to think of a good example, but I really can't think of a pic to link to. Anyway, when you sand after etching you're removing the etched steel. In my experience with 1084, I can barely see the temper line at 320-400 grit without etching if I angle the blade right in the light. But, Japanese swords have beautiful temper lines (hamon) without any etching, brought out by the special finishing and polishing process they use. If you can get a 1000-2000 grit finish on it you'll see the temper line on its own, but it woon't be as dramatic as an etched finish.

What I generally do is finish to a good 400-600 grit finish by hand, get a good etch using ferric chloride, then use wet steel wool to smooth it out and lighten it up a bit. That seems to work nicely for me. Hopefully Mike Burch will chime in because his temper lines are unbelievable! Here's what mine typically end up looking like using this method:

So, your temper line is still there, you just have to make it show itself!

 

[Burchtree]

When you etch the two sides oxidize differently and that's why you get the nice line. Getting a good "western" line is a balance point between polishing the oxidation off while still maintaining the difference. Leave the etching until after you've sanded the blade (usually 1000grit or more) then stick it in the etchant for just a bit. I few wipes with simichrome or flitz will clean up the really dark oxidation and still leave you with a nice line. Of course, the fun is in experimenting, so try plenty of different stuff -- there are a thousand different ways to make it work for you.

Good luck, and show us some pics!

Edited to add: Thanks for the kind works Steve, but hopefully some of the real hamon specialist will chime in with some advice.

 

[Chiro75]

Edited to add: Thanks for the kind works Steve, but hopefully some of the real hamon specialist will chime in with some advice.

Is Don Fogg a member here? Trust me, Mike, your hamons and finishes are some of the best I've seen (either that or you're a whiz with the Photoshop!), so there!