Blackening brass advice

[Bossman]

Ladies and gents, i blackened the cannons for the Confederacy I am building. I used dvm27’s excellent tutorial on this. As you can see, my first batch did not turn out so good. The second batch is perfect. I figured out what I did wrong with the first batch. My question is, doi need to take the first batch back down to brass before re blackening or just redo? Thanks in advance for advice. 

[James H]

I would make sure your parts are thoroughly degreased before blackening them. A good way to do that is to wash them in acetone or ethanol etc. 

 

That 'might' be your issue. 

[Bossman]

James, thank you for the quick reply. As you can see, the second batch is perfect. Yes, they were both pickled, neutralized, cleaned in acetone and blackened. Actually, the culprit was not leaving them in long enough. My question is, when I redo the bad batch, do I need to take them back down to brass first and start from scratch or just redo following the above without taking off what blackening is there. 

[allanyed]

Boss,

If the culprit was not pickling and cleaning long enough, the contaminant may still be there.   If you have a small wire brush wheel for a rotary tool, I would use that first and get back to bare metal then pickle and degrease.   If not, you can try  to  just pickle it again, then clean with the acetone before re-blackening.     I am pretty sure most of us have had the same issue at times and these methods have worked for me in the past.

Allan

 

[Bossman]

Allen, thank you Sir! I’ll take it down and redo. 

[Jorge Hedges]

Hello!  What is the link for the tutorial?  Thanks!

 

EDIT - Never mind...  just found it.

 

Thanks again!

 

Jorge

 

[James H]

I hope you post your results after this.

[Bossman]

2 hours ago, James H said:

I hope you post your results after this.

Will do!

[dvm27]

I agree with Alan. Second attempts have not turned out as well for me. Go back to bare metal using a wire wheel to get in all the nooks and crannies. Congrats on the good results for the other batch!

[Jorge Hedges]

Just ordered all of the products for the blackening process as well; will post results plus any observations during the process.

 

Thanks!

 

Jorge

[Beef Wellington]

You don't mention how you used the blackening solution and how much you diluted.   I've found results to be much more predicable with a more dilute solution, and using a nylon brush to apply while agitating the surface.  Once the reagent is spent on a small area (turning from blue colour to brown), then the brush can be simply washed in water, dried on a paper towel, and a fresh brush load applied.  I've had much less predictable results using a larger 'bath' to submerge items in.

[Bossman]

Jason, I used about 1 to 7 Jax Black and Water respectively in a bath. 

[Bossman]

Update. I finally got around to redoing the 1st cannons that did not go well. I first steel wooled the crap out of them and then reblackened following the tutorial. Success. There is a glare in the picture but they are a nice even black. Greg, thanks again for the tutorial. 

[dvm27]

Those look great. If you're wanting to go a step further you can use a felt or flannel polishing pad attached to your Dremel or regular drill at low speed. It gets into all the nooks and crannies and creates a perfect uniform polished finish. Depends on your preference.

[Bossman]

Thanks Greg.  The picture was taken just after blackening and a quick wipe with a cloth to make sure it was  permanent. Thanks again for the excellent tutorial.