Damascus Etch Question

[PeterAtwood]

I've looked through the past threads and there seems to be quite a few different ways to arrive at success. But none of them are quite working for me. I'm getting a spotty etch, or I should say, I'm getting an etch, just spotty contrast. The metal is getting eaten away for sure but it is not developing a black oxide layer in a uniform manner. Some areas are very black and others have nothing but the layers are distinct.

The bevels have the best finish. They etched quite deep and I have now masked them off with nail polish while I work on catching the rest of the blade up. They were finished with a fine scotchbrite belt.

The flats are where the trouble is. They were finished with a Norax belt to approximately 400 grit. During the course of the day I have refinished the flats with the scotchbrite belt thinking I had better match the bevels for consistency. Still no effect. There are some areas that just won't seem to turn color no matter what I do. But other parts of the flats have etched deeply and are showing a dark black. I mask them off as they are done.

I'm cleaning the steel with acetone then windex then scrubbing with dish detergent and rinsing well. I'm careful not to touch the blade with fingers. So I don't think it a finger oil or dirt issue.


I'm using 4 parts water and one part ferric chloride on Devin Thomas SS damascus. The original solution was 50-50 ferric and water and was not warm but I have also tried it with a warm solution.

Right now about 90 % of the blade is done enough and is masked off with nail polish. It's just that last little bit that would make the blade really look finished.


Any ideas? I'm sure it is something I'm doing wrong and it can be fixed.

[GANNMADE]

try hand sanding to 800 grit then etch repeat until you get a good etch.this is what works for me.

[Ray Rogers]

I have used that steel and had very good results with the 50-50 ferric chloride mixture. From your description of your process it sounds like you are doing everything right. However, one thing you said may raise an issue.

You finished to 400 grit and that is what Devon recommends but he says use a sharp belt. You used a Norax belt and sometimes Scotch brite. Neither is really a 'sharp' belt. I wonder if those softer belts are blurring the harder steel over the softer parts and blocking out the acid? That might explain the splotchiness that you experienced and why you were able to over come the problem in small areas.

Anyway, it's a thought. Try a conventional belt or maybe even hand sanding .........

[PeterAtwood]

That would make sense Ray, except the bevels came out so crisp and clear with the scotchbrite. Well, I will certainly give it a try anyway with a sharp fresh belt. Maybe that is the answer after all...

So, normally you guys are getting uniform dark adn light areas all over the blade? Or does everyone go through this same sort of selective etching?

Thanks!

[Ray Rogers]

With a high quality piece of steel like that, I expect to get it the first time. On Devon's steel, I finish to 400, clean it, drop in it warm 50-50 for 10 minutes, wash it in water and dry. That's usually all it takes but if necessary I'll put it back for 5 more mintes, wash, dry, etc until I get it as dark as I want it .

One thing: when you wash in running water you rub gently to remove the acid and the loose deposits. 'Gently' is very important as it doesn't take much to rub the black deposit right off the blade. After it dries for an hour or more the black 'sets' and is much harder to remove....

[Brett Schaller]

I hand finish the flats with a fresh piece of 400 silicon carbide paper on my granite block, and the bevels with a fresh 400 belt on my contact wheel. This seems to help keep the etch pretty consistant throughout.

[PeterAtwood]

Well, I totally refinished the blade and tried again this time with a brand new bottle of ferric. Wow! What a difference. After 5 minutes I had a clear crisp etch. I'm thinking it was the ferric. must have been at least 2-3 years old and at this point I was no longer positive of the dilution percentages.