Instructor TIP-Etching Without ACID

By pipewelder_1999 (****)

Date 01-27-2015 04:58

Many may already know this and many may not have any issues with handling acid. I would think HS instructors may be limited on what they can do when it comes to etching.

Regular White Vinegar from the grocery store will do a pretty decent job but itt may take a day or so. Attached are some pics of a few pieces that were etched this way.

By welderbrent (*****)

Date 01-27-2015 12:43

And when only for educational purposes or personal curiosity that is a great idea.

BUT, for certification purposes I don't believe it is acceptable. I'd have to look closer at some of the guidelines for macro-etching but seems like the acids are established as to strengths and variety. Could be mistaken, don't do enough of it and already have my procedure established. Anyway, any of those established as ATF's would need to make sure of what was required.

He Is In Control, Have a Great Day, Brent

By pipewelder_1999 (****)

Date 01-27-2015 13:00

I do the Weld Tests with quicker acting acids . But I would not restrict someone from doing this should the code in question not specify what should be done.

BUT AWS D1.1-2010 says "A suitable Solution shall be used for etching to give a clear definition of the weld. "

Other codes are a bit more specific but even those in Sec IX are "Suggested" but do require a visible heat affected zone.

I have seen manufacturers use a torch and heat tint.

One thought though on the level of detail needed, typically the only thing being looked at is penetration, fusion, and discontinuities of a size that can be seen by the naked eye. (1/32" in the case of Section IX for Performance)

Have a good one.
Gerald

By TimGary (****)

Date 01-27-2015 13:51

I recently found that using "Eazy Off Heavy Duty Oven Cleaner" works OK for etching aluminum.

Tim