440s is pretty hard, huh?

[Eric Olson]

I have been practicing on a "tree" brand pocket knife that I found at a flea market.
I engraved the spring along the back of the knife (with much sharpening and changing of angles),
But when I tried to continue the pattern on the back of the blade it seemed impossible.

Should I give up on the blade?

Thanks-

 

[Sam]

For all pracitcal purposes, it's impossible.

 

[Ray Cover]

I would not mess with the blade. For what it's worth you may not have done the knife any favors by engraving the spring. By engraving the spring you have in essence created break starts all along he spring. A brick layer will score a brick then tap the brick with a hammer to cut it. The brick breaks along the score line he made. The spring works the same way. when that hardened steel gets put under pressure all those cuts do the same job the score line on the brick does. You may get away with it for a while but it is taking a great risk engraving a spring, especially with any line that goes all the way across.

A lock bar on a lock back you can get away with but springs are very risky for breakage.

Ray

Ray

 

[BrianPowley]

Is 440 hard?
As my dad would say, "Harder than Chinese Arithmetic".
About the only thing I can do with those blades is diamond drag pantograph them. You ain't gonna cut it.

 

[billrice@charter.net]

Hi Guys

The question of is 440 Stainless hard in this context is about a steel that has been Heat treated stainless steel. Yes this is going to be imposssible to hand engrave as Sam has said and I throughly agree with Ray on the spring since this also has been heated treated to spring hard.
However some knife makers use 440c stainless not heat treated for the knife handle parts such as bolsters. Which you can Engrave.
Though stainless is not like mild steel, brass, copper,silver or gold it has a toughness depending on which model of stainless you are working with that you can apply the methods that have been talked about on this forum.

Just thought I would put my 2 cents in

 

[KSnyder]

knife springs are file worked before hardening & tempering. Tree brand was Solingen, Germany till Boker changed that, I think they went to the dark side, (China). its never a good idea to try to cut something that is made to cut something as generally its too hard.

 

[Brian Hochstrat]

440c is tough engraving even in it's annealed state. Many integral knives are fabricated out of it. I did one for Ron Best a few years ago, it was not fun. The first and certainly the last integral of my career.

 

[dimovengraving]

...Should I give up on the blade? ...

After hardening, 440C have near 60 HRC
I have bad memories , even in engraving of unfired 440C

 

[willy]

Annealing 440c : Full annealing range is 1550-1650 degree F. Cool slowly in furnace.
Hardening : 1850-1950 degree F, quench large sections in oil. Small sections may be quenched in air. Temper as required.

 

[monk]

i've engraved many blades over the years. fortunately, the makers sent them to me in the annealed state. even in that state, some were miserably tough to work with. i'd never try one that's been hardened. the only exceptions are acid etching, pantograph, laser, and rotary diamond. none of which are really hand engraving.

 

[Marrinan]

I currently have a knife on my vise that is made out of a sawmill saw blade. Hardened by years of heating while it did its work. Carbide has barely able to scratch it. Since it is way to hard to a decent job of cutting I decided to venture into "strong water" territory for the first time. Currently going through the tutorials on the Café forum about the use of acid and mordants to accomplish a monogram on it. Will see how it comes out. The knife was made by a friend using a bench grinder rather than belt grinder and the finish is taking quite a bit of time to get a nice job on. I owe the guy a couple of favors so it is a free-bee but I try to do my best work always. -Fred