Blackening brass problem

[Maury S]

I've run into a problem blackening some brass parts.  I've done it hundreds of times before without a problem.  Sand or file the pieces, pickle in vinegar for an hour and rinse.  Soak in Acetone for an hour and rinse.  Put in 1:5 dilute Blacken-It for an hour.  There is a reaction, but the result is a pinkish color, not black.  Does Blacken-It go bad?  Mine's 5 year's old.  I understand it's not sold any more.  I used Apple Cider vinegar the first time and thought it might be that, but a repeat of the process with white vinegar produced the same result.  Any thoughts?

Maury

[Tadeusz43]

Hi,

Try again with new Blacken-It .

This you have lost of power.

Most of the chemicals is limited shelf life.

 

Tadeusz

[figuerres]

I have heard that this can be used, "Birchwood Casey Brass Black"  look on amazon or at gunsmith supply places

[Dan Vadas]

I have heard that this can be used, "Birchwood Casey Brass Black"  look on amazon or at gunsmith supply places

 

That's what I use. You only need to soak the piece for a minute or two depending on how "black" you want it.

 

 Danny

[egkb]

I've had mixed results due to the brass used being of different (poor ?) quality compared with previously successfully blackened brass.

 

Eamonn

[Maury S]

Thanks all!

Maury

[gjdale]

Maury,

 

Sorry, I posted on your build log before I saw this thread. I started using the Birchwood Casey brass black on Danny's advice after a lot of unsuccessful attempts with Blacken-it. I haven't had a problem since, including soldered pieces.

[kurtvd19]

I too am a proponent of Birchwood Casey Brass Black.  Pickling in vinegar for an hour is OK I guess.  I use warm Sparex for that for 10 minutes or so and then a rinse in water.  If you do a rinse in acetone you only need to do so for a few seconds - longer isn't doing anything except wasting time.  Dip the clean brass part in the Brass Black for just a few seconds using tweezers - keep the part moving gently while immersed and then lift out with the tweezers, and let the solution drip back into the container.  Dip again and let it drip while watching for the degree of black you want.  Don't soak for extended times it will build up a crust that will flake off.  Rinse well in water and let dry - don't handle the part.  If it's not dark enough repeat the process in the Brass Black - no need to reclean or soak in etch if you don't handle with your bare fingers. 

I don't dilute the Brass Black (always did so with Blacken It but I will not use it for brass again) and can't advise one way or the other on doing so but even diluted I would not leave the part in it for any length of time.  Hold the part with tweezers and agitate the solution by moving the part gently in the solution and you will get good blackening.

Kurt

[hornet]

Another fan of birchwood casey brass black. It is available on eBay by the way. I have had a couple of failures with it but I suspect that the brass content was not high enough to get a good chemical reaction going in those cases. If blackening is unsuccessful, might I suggest using admiralty acrylic paint - matt (metal) black. I have had excellent results with this paint. It looks just as good as genuine blackening. .

Edited February 18, 2015 by hornet

[Maury S]

I've ordered the Brass Black.  Kurt, thanks for the instructions for use!

Maury

[tlevine]

Maury, I typically dilute the Birchwood Casey 1:10.  I have never tried it full strength.

[FredSC]

Query:  If Admiralty black acrylic (which I have used) works as well as blackening, why go to the extra trouble?

[hornet]

I use the blackened because you can get different 'shades' according to how long or how many times you soak it. It is also quicker than painting which is an issue if you have a heap of cannons to do. You also don't have to wait for it to dry.

[Dan Vadas]

I use the blackened because you can get different 'shades' according to how long or how many times you soak it. It is also quicker than painting which is an issue if you have a heap of cannons to do. You also don't have to wait for it to dry.

 

To demonstrate hornet's post above, you can't get this kind of effect with paint (unless you're a VERY good painter) :

 

 

 

 Danny

[FredSC]

Thanks, Dan.  I'm convinced.  There's nothing like actually seeing it.

[Dan Vadas]

Danny

 

How long at a time do you soak it in Blacken It before letting it drain

 

Geoff, I use Birchwood Casey Brass Black - not Blacken-it. The B/C only needs about 30 to 45 seconds to do the job.

 

 Danny