There was a great thread a while back about this and I learned alot from it. I am now working on a 1095 hunter that has a pretty good "temper line" but I am having a hard time bringing it out the way I want.

I have etched and sanded a few times but never with the results I want. At first it either stayed too oxidized or I sanded the line out altogether--I am looking for something in the middle. Well, now, after several etches, the steel from the middle to the back polishes up nicely but the steel along the blade is "permanently" oxidized and very slightly pitted. The difference in the grain/texture of the two sections shows a sort of temper line but I don't want to leave the blade in a condition that looks mildly corroded.

I took the blade to 600 before etching and polished with 1,000 and 1,500. I think this may have "smeared" the etch a bit.

Also, and this was really interesting to me, along the transition zone, small portions of the steel grain are somewhat open and "woody," looking almost like the grain of a pourous hardwook like walnut. It almost looks like 60 grit scratches were left in the blade along the temper line. Can this happen in the quench, the same way previously unseen flaws open up in damascus when hardened?

I know in the last series Ed recommended taking everything back down to 400 and going from there. I will probably do this. But what are my other options?

Thanks,

John

Hi John!

Sounds like you've really gone after the etching! Great! 1095 is one of those steels that sometimes etches great and other times you work yourself to death just to get a temper line to show up.
If you've gotten those pits in the edge section, and the "woody" grain in the transition zone, it's just spent too much time in the etch.
You basically have two options.......1. You can leave it like it is. 2. Regrind it, starting with a 120grit, and working you way back down, then etch it again.

I really hate to see those little pits show up in the edge....they are a real booger to get rid of, and it seems that by the time a person manages to "erase" them, you've just about run out of blade.

Concerning the 60 grit scratch looking stuff. It's very likely that those are a magnification of a scratch that were missed during hand sanding. Prior to etching, you must examine the blade very carefully to ensure ALL scratches are gone, even those tiney "shadow scratches" which are the ones only visibile as shadows when you turn the blade this way and that under a strong light, will etch out to look horrible in the finished blade.
Try different methods of cleaning up after the etch. Make sure you soak in baking soda or TSP to kill the etch, and then try #0000 steel wool, or flitz/semi-chrome, or a combo of the two. I've found that with the flitz or semi-chrome you can achieve whatever level of finish you like, just by how long you work at it.

Come on folks, let's hear some other comments that I missed!!

About those "shadow scratches". The lighting in my shop ain't the best and I've had them show up later on. I now take a "Sharpey" permanet magic marker and color the whole blade between belt grit changes. Once I'm done with 60 grit I color it . While I'm using a 220 grit, all the 60 grit lines show up. Do this all the way through 600 grit. It is very easy to see any missed scratches, they stay black until ground away. Less strain on the eyes also.

I was going to suggest a little ferric inbetween grit to show the some times evasive scratch. I'm not an expert on bringing out a temper line with etchents, but if your interested I will leave a thread on exactly how we sequentaily temper 1095. The temper line is highly visible due to oxides that form on the blade at dif. temperatures and no pitting... Of coarse there are other pitfalls

http://www.aptelcommunications.com/images/userSubmitted/16/16_4_4649_image.JPG

If you are interested in trying your hand at the torche draw, then you get the most visible line. Check out our site under Tech. Info./Methodes.

By the way, I know that there are many ways to skin a cat. I was always skeptical of the use of a torche on a blade, or a brine quench, but for no good reason. We have flexed 1095 after 1095 peace and its rugged will flex 90 deg. with just a blue spring back (no gray normalized steel). The oxide on the blade also prohibits rust.

Hope you get your temper line.

Your problem sounds like too mutch etch all at once. If you're getting pits, i'm assuming you're using ferric chloride to etch with. It's a salt and works very fast and has a tendency to pit things at higher concentrations. Naval jelly does the same thing.

Try shorter etching cycles with light sanding in between each cycle (like with 1000 grit paper, just enough to remove the oxides). I like to use very dilute etchant (4-5 parts water to 1 part FeCl board etchant already diluted straight out of the bottle). I etch for about 20-30 seconds, then lightly sand, then etch again. It gives a softer, more even appearance.

A 4-5% nitric acid solution is a really nice etchant, again with multiple cycles.

Thanks.

So am I correct in assuming the FeCl attacks the hardented steel more aggressively and that is why I am getting the pitting only there? Or is it that the pitting sands out of the softer steel more easily? Or a combination of both? Somehow this is counterintuitive--I would think that the softer the steel the more quickly it would etch.

John

yep, the hardened steel gets etched quicker. FeCl is nasty stuff if you're steel, but pretty safe otherwise. Think of it like acidic saltwater. Vinegar etches nicely as long as you break the surface tension.

Thanks to everyone. This blade is deeply etched and already pretty thin, so regrinding is not really an option. I took it down to 400 and still have a visible "temper line" simply due to the mild oxidization/corrosion of the hardened portion. Fortunately this knife is being traded for elk antlers and the eventual owner already implied that he wanted a sort of antique finish to the antler and a brass guard rather than nickel silver to complete the old look. So this piece will be sort of a differential hardening meets buckskinner. I am finally getting a digital camera and will try to post pictures soon.

You guys are the best,

John