I just found a great way to get orange peel texture on D2.
After heat treating and tempering some D2 blades that I had run to 400 grit before treatment, I tried cleaning them up with a 400 grit Scotch Brite belt. This produced the most complete coverage of orange peel that I have had so far.

Needless to say, I won't repeat this experiment.

I did the same thing and got the same thing. For one, I actually LIKE the orange peel texture. But basically whats happening is that the "soft" abrasive texture of the Scotchbrite belt is eating away at the softer matrix quicker than at the notoriously coarse (but hard) grain of the D2 carbides.

You want more orange peel - try this. Finish to 1200grit, then 2-5 minutes in ferric chloride, then either Scothbrite again or buff - it will look a little like "Crazy Wootz" !!! :D ;)

Someone I'm sure will have a use for this.... Jason.

I thought the orange peel was caused by plucking of carbides on the surface.

I have gotten very interesting random wootz like texture by etching in undiluted muriatic acid (.375 N HCl) for about 15 minutes. This gives a dull gray colored finish. I haven't run into anyone but me that likes it, though.

I etch all my CPM-3V blades and many 154CM and S30V blades in Ferric Chloride for about 10 minutes. I then brush it out to get a durable nonreflective finish that I like better than bead blasted. It's also more corrosion resistant, essentially the same as passivating the steel. I haven't tried Muriatic Acid; I'll have to see how it looks. How long do you leave it in the acid?

I haven't tried any CPM in muriatic, but 10 minutes for D2 gives a dull solid gray finish. At 12 to 15 minutes you can start to see a grain structure that I assume to be carbides on the surface.
I think it really pulls the chrome out as the acid gets a very greenish tint to it.

BTW, my FeCl is 50% in water. With the HCl you're also making FeCl and that's greenish in color as well.

One problem I've had with S30V treated this way is that it is occassionally less homogenous than the other steels, so you sometimes see strange spots or small areas that etch differently than the rest. In those cases, I remove the finish back to full bright.

Using an resist, you can do some interesting things with acid. I call this, Yuppie Camo.

http://hossom.com/test/index_image044.jpg

I like the yuppie camo. Do youi coat the unetched areas with paraffin?

The uneven etch is one reason I don't do it more often. It seems a high percent of blades seem to have spots or streaks of slightly different texture.

I have been mixing FeCl with white vinegar, a method that was recommended by a damascus dealer i have used.

I use artists' etch resist like that used on copper plates to make etchings. It's call Universal Ground and I get it from Graphic Chemical and Ink Co in Chicago. They have a website, but I don't have the link offhand. It's very thin and you can just paint it on with a soft brush. I think those blades were etched for 30 minutes in the FeCl.

What quality does the white vinegar add to the FeCl?

I am not sure on the vinegar, I have assumed it was used as a pH buffer. I only use it when I want the solution to be strong, as for a black finish. I got the recipe from the makers of ThunderForged damascus.