Tuesday, August 17, 2010

Acid etching

I used the same sample piece of copper for etching with ferric chloride since it was still masked with duct tape from Etching Round 1.  I traced over the monograms with a Sharpie oil-based paint marker as the resist, which seems to have a more consistent application than a regular Sharpie but is much easier to use than nail polish.  (Available in three thicknesses where art supplies are sold, in my case at Michaels.)  I let the copper plate sit in the etching solution for about an hour, checking it every 20 minutes or so to see how it was going.  It's hard for me to tell how much etching is happening because the resist itself is three-dimensional, but finally I couldn't wait any longer so I rinsed the piece off and removed the resist with acetone. 


You can actually see both rounds of etching in the top of the closer monogram and the circles around both (which were only salt water etched).  Etching is a much more subtle texture than what I normally do with PMC.  And, like I said, it's hard to tell how much etching is happening during the process, so I guess salt water etching was more effective than I thought. 

At least now I can honestly say I can etch copper.

2 comments:

Mary Meyer said...

Nice. This looks great! But did you know that there's also a dental treatment called 'acid etching' where they make use of an acidic chemical substance to prepare the tooth enamel and or dentin surface to provide retention for bonding. Do you happen to know if it's the same acid etching technique as what you did here?

Anne said...

Hi, Mary. Thanks for your comment. Acid is used to etch or give "tooth" to many types of surfaces. Different acids are used, depending on the surface. I am not a dental professional, but I doubt something as toxic as ferric chloride is applied to teeth.