Cleaning a tight pattern after etch?

[M&J]

This is a Daryl Meier piece that I etched today. Any tips on cleaning it up when the pattern is so tight that getting between the ridges is difficult. I leaves it splotchy and has some lines that I don't like.

I thought I finished it evenly enough prior but it has me wondering if I've done something wrong along the way. I suspect that I'll rub it out then etch again.

Tips-suggestions...?

[billyO]

Originally Posted by M&J

Any tips on cleaning it up when the pattern is so tight that getting between the ridges is difficult.

What grit? I finish my damascus with 5000 grit paper.
RE: tips - make sure you have your paper tight against whatever backing piece/sanding stick you are using.

But if it's a really high layer count (>300-400) then this is possibly something that you won't be able to change as it's the nature of a really high layer count.

[M&J]

I initially used a brass wire brush to get the chunky stuff off then rubbed with 3M 6000G/2micron polishing paper. That wasn't progressing well so I also tried a lead remover polishing cloth which actually worked fairly well. I'm unable to remove some of the deposits so it has a splotchy look including those lines.

It looks like I over rubbed it which wasn't the look desired.

[Ed Caffrey]

Originally Posted by M&J

I initially used a brass wire brush to get the chunky stuff off then rubbed with 3M 6000G/2micron polishing paper. That wasn't progressing well so I also tried a lead remover polishing cloth which actually worked fairly well. I'm unable to remove some of the deposits so it has a splotchy look including those lines.

It looks like I over rubbed it which wasn't the look desired.

I might not fully be on "the same page"..... Are you saying that you didn't do any hand sanding/finishing on it? If so, that is a big red flag to me.
When preparing damascus for etching, nothing will give you better results then hand sanding/finishing it. Even with a very fine machine finish, the etch simply will not come out looking as good as hand sanding.
Also, any type of buffing/polishing is a big no-no....the etch has to have something to "bite"....and very often a polished finish on damascus tends to results in blotchy/smeared looks. If that "lead remover polishing cloth" has been used on anything else/before, it's likely a contaminate.

It's obvious to me from viewing the pic, that the piece has the potential for a lot of chatoyance.... it just needs better prep before etching.

OK.... all that being said, if it were me, I would go to the grinder with a new 220 and clean the piece, then to 400, and 600. Then go to the bench and hand finish starting with 400, and go to at least 800. If you want the chatoyance to jump out... take it to 1200-1500.

I'm sure this is preaching to the choir, but CLEAN is the name of the game! I guess I should not make any assumptions, and ask what you are using for etchant? Hopefully Ferric Chloride.... that is going to give you a higher level of etch quality than anything else.

I typically put on the latex/nitrile gloves, clean the damascus with acetone and a CLEAN/NEW cotton rag, or if you use paper towels.... ONLY the scott brand blue "shop towels" variety. (typical paper towels, that are white, are processed with some type of detergent during production that will leave a film when used with acetone, and will cause streaks and smear in the etch). Then clean it a second time with windex, dry and then use compressed air to ensure it fully dry..... then into the etch. The etchant should be around 70F (Ferric Chloride) and diluted 3-1 or 4-1 with DISTILLED water. A slower etch always produces a better overall etch on damascus.

Here's a link to a really old video of mine on etching....but it's still true and useful: https://www.youtube.com/watch?v=7NknW9Z7_pI

[KenH]

Ed, that info is what I've followed for etching with good results. One thing that can bite you, "IF" the FeCl etching solution has gotten contaminated the etch can be affected. When having problems with an etch, first this is new clean etching solution.

Ed, you're still my mentor

[M&J]

Thanks Ed.

I'd finished it up to a 1K grit level then etched it. It's not coming along as I would like so I may mix up a fresh batch of ferric chloride to see how it does. This has been the more frustrating sample I've had in a spell.

After the sanding was sprayed with a degreaser and wiped it off with an unprinted paper towel. This particular degreaser leaves no noticeable film and the same one I've been using for the past 15+ years. (It isn't allowed in CA due to EPA so you know it is good stuff. LOL)

Edit additional info:

On the second etch yesterday, put in the solution for about 10-12 minutes and it was at a level I liked. Ambient temps are running 75F now so just about right. Neutralized then rubbed with 4000G 3M polishing paper. Still unhappy.

The depth is great and it does show lots of promise but not at a finish level that I want it to be. The first one I had issues with too and that was done about 20 years ago. Similar complaints and redo's as well. I may be working it incorrectly to get the desired results.

I've not struggled this much to get looking good. Been quite a learning experience.

[Ed Caffrey]

Now it becomes a process of elimination.... trying to find what is causing the issue where it's happening in the process.

If your ferric is over a year old, or if it is possibly contaminated, then mixing a new batch is a good idea. Just remember to mix it, and let is set overnight before you use it.

I can't be sure of what to say about the cleaner you use.... except to suggest you try the acetone, then windex cleaning. When you say "unprinted paper towel".... is it the white paper towels most folks use? If so, then that is very possibly at least part of the issue. ANY paper towel that I have tried, will leave a film that impedes etching. The ONLY "paper towel" I've found that doesn't leave the film are the blue colored "Scott Shop Towels" paper towels. Clean cotton rags work too.

Sounds like the etch temp is good....and the time too. I typically don't make time the determining factor when etching.... I typically etch until I can feel the topography with a fingertip. That tends to be a shorter length of time for tight patterns like in you pic.... and longer for larger, more open patterns.

Once the etching is complete, the after actions are important too... Neutralizing the etch is imperative. A saturated TSP solution (tri-sodium phosphate), with a few minutes soak. Keep that "dark" or "black" which happens in the lows of the topography is a challenge. Folks try all kinds of things to keep it, but as it comes out of the etch, you want to get rid of that stuff....it is nothing more then sludge, from dissolved steel. If left, it acts like a sponge drawing moisture, and causing rust.

Were it me, and considering the what I see of the damascus in the pic, I would etch it to depth, then after neutralizing, scrub it in clean/soapy water with #0000 steel wool until clean. It should start to show some chatoyance by then, and then would give it a good cleaning/polishing BY HAND with a clean cotton or microfiber cloth, and something like Wenol, or Flitz metal polish. This is not something I often do, but it is effective on tight patterns that have the potential for good chatoyance (such as I see in this piece of Damascus).

I didn't see what the steels where in that damascus, but that can possibly have an impact on the etch too. Most of the time I assume folks are etching/using 1080 or 1084, and 15N20.

[M&J]

Thanks Ed.

Called the electronics shops in the area and both were out of ferric chloride. One had some coming in on Tuesday and the other had no idea when to expect it. After I get some I'll revisit.

I don't recall the steel composition on this one. Any thoughts what Daryl Meir was known for in his damascus from the early 2000's? Want to recall I picked the bar up at the Orlando Guild show.