Q. for folks who have tried electro-etching

[WalterK]

When done on stainless steel, is the surface-feel of this type of etching smoother/similar/coarser than sandblasting?

 

[WalterK]

bump

 

[bberg100]

No one? We finally found a topic with no experience here?
Having done a fair amount of sandblasting I have never got as smooth of finish as etched items I've bought.

 

[Slash McCoy]

I never tried etching SS.

 

[WalterK]

Thank you for the information, it's very tough to judge smoothness from pictures and youtube videos.

 

[That1guy]

When etching i have always reversed polarity to give a deeper "etch" but one thing i noticed was the solution (salt water) when fresh and watered down would give a smooth even etch but in a few minutes would start to thicken and get chunky from the "swarf" and start to etch closer to the sand blast you are talking about. So if you want a smooth consistent etch you will need a fresh solution to conduct your current evenly but remember different solutions will have different properties. So far i have only used salt and tap water but now i am wondering if using distilled water or the vinegar solution would give a smoother finish. But in the end the more consistent you can transfer the electrical current to the area you wish to etch will give you the smoother finish and vise versa. Sorry for the jumbled ramblings as i'm a few beers in, hope that helps.

 

[WalterK]

... in a few minutes would start to thicken and get chunky from the "swarf" and start to etch closer to the sand blast you are talking about...

According to your experience, could a finish rougher than sandblasting be possible?

 

[That1guy]

Definitely, when the solution starts to thicken up to a paste consistency it starts to roughen up the finish the deeper it goes. Since electro etching is a forced corrosion of the metal just think of how rust progresses by stage, light rust only penetrates the surface and discolors but can be wiped off and you still have a surface finish similar to how it was originally but heavy rust starts to eat down and pitting occurs with a rough irregular surface finish. I might have this backwards but (-) to the work piece and (+) to your electrode will discolor and "anodize" in a way the surface where as (+) to the work piece and (-) to the electrode is where the forced corrosion is done and the etch will penetrate into the material. One last thing, when the solution starts to thicken it really slows down the etching but refreshing the solution doesn't make the etch smoother so you will not loose the rough finish you are trying for.

 

[WalterK]

Definitely... will not loose the rough finish you are trying for.

Thank-you, I see experimentation in my future!

 

[Slash McCoy]

Also after conventional cathode etching (negative dc electrode, positive ground) you can bypass the rectifier and go straight from the transformer with 9vac to 24vac whatevah and this will blacken the etching nicely. At least it does on carbon steel.

 

[WalterK]

Thanks Slash

 

[That1guy]

very cool now slash has my mind going. @Slash i wonder if we etched DCEN then used your process or DCEP with a Patina solution to plate the etch with copper or colors. I know of a few local shops that have a wide selection of metal patinas so next time i go i will ask them if they have a solution that is not toxic and works well with simple DC power.