Brass Blackening

Kramer

Kramer

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Hey shipbuilders! I have a question about brass blackening for those of you with experience with it. For the brass blackening, does anyone know how long until it's totally set? I've let it sit for 24 hours and it's dry, but still a little chalky and rubs off a bit on my finger. Just curious if it's always going to be chalky and I can handle it now. I'm using Birchwood Casey Brass Blackening. It looks great! Nice and matte, deep black, doesn't look like paint. Very easy process...if I did it right. I soaked the pieces in acetone first for 5 minutes, then dried them off. Put them in a bath of brass blackening which worked immediately.
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Did you dilute the Brass Black? If you leave it too long then it gets chalky. The length of time you leave it depends on the strength of the solution. I read somewhere that making a very weak solution and soaking a long time makes for a more durable finish. I haven't tried that. I use a 50/50 mix. What I try and do is get it out just as it starts to turn blackish, not the deep beautiful black that comes with longer soaking. Once it's on the ship the blackish finish looks fine to me.
 
Don Case said:
Did you dilute the Brass Black? If you leave it too long then it gets chalky. The length of time you leave it depends on the strength of the solution. I read somewhere that making a very weak solution and soaking a long time makes for a more durable finish. I haven't tried that. I use a 50/50 mix. What I try and do is get it out just as it starts to turn blackish, not the deep beautiful black that comes with longer soaking. Once it's on the ship the blackish finish looks fine to me.
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Hey Don, I did not dilute it. Hadn't heard to do that. And I may have left some pieces in too long. I assumed you I had to leave them in for a long time, but after seeing how fast it worked, I started taking the pieces out after a minute. Some tiny pieces got a longer bath as I hunted for them in the solution. Do you dilute it with just water?
 
Yup. I don't know if it should be distilled water. Brass Black is acidic so alkaline water may affect it. Maybe someone else can help with that. We are blessed with very pure water(we can fill batteries right out of the tap) so I don't think about that much.
I diluted some and keep it in a second jar. It seems to last a long time. I don't think the dilution rate is critical, just the more you dilute it, the longer the soak.
 
I found that leaving the pieces in just long enough to darken, removing and rinsing in water, then buffing with a soft cloth (old t-shirt) will provide a nice dark patina. Leaving it in too long causes too much corrosion and wipes pretty much back to brass when burnished. I have left a piece in over night and it badly corrodes the brass and eventually will dissolve it completely. Periodically, I filter the solution through a paper filter to remove the crap and wash the jar before replacing. I also bought 'Brass Ager' from Amazon. It works well, is way cheaper than brass black but ages the brass MUCH slower. Screenshot_20230122-091956_Chrome.jpgScreenshot_20221119-185117_Gallery.jpg
 
I took Philski's advice and rinsed the pieces in water and laid them out to air dry. The pieces are so small there'll be no buffing, I'll just have to go with what I've got. I don't have to use the pieces for a while so hopefully time will help.
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Casey's Brass Black is a super product. Preparation of the brass is crucial. Once out of your acetone bath the pieces should not be handled with the human hand. Otherwise oils from our skin will cause issues.

I use a 1:10 ratio of Brass Black:Water. As expected it takes quite a bit longer to blacken. Stir with a paint brush or wooden stick. Something without any metal on it. With a diluted solution the chemical reaction is slowed and allows you to inspect over time, rather than the brass turning black quickly with a "scaly" or "chalky" appearance. TIP: if you do end up with a rough appearance, you can take a small container, any thing you can seal. Put some regular sand and fill to about 3/4 full. Add you small pieces and then gently shake it for about 10-15 mins. The sand will gently scrub the scale and chalky residue off your blackened brass and you will be a happy modeler.
 
I use the brass black straight from the bottle. After cleaning the brass, I soak in Isopropyl alcohol, then let it dry before putting in an empty container and adding just enough blackening solution to cover the parts. I gently agitate the solution till the parts just turn then fill the container with water and drain and continue to rinse with clean water. I then put the parts onto a paper towel to dry. Yes there will be some residual powder but parts can be gently brushed with a soft brush and they will have a dull black/blue sheen.
If you leave the parts in the solution too long, a thick coat will result and this will flake off regardless of how well you prepare the parts.
You can not make brass turn black. Your are only trying to create a patina on the brass, not coat it.
 
peter6172 said:
I use the brass black straight from the bottle. After cleaning the brass, I soak in Isopropyl alcohol, then let it dry before putting in an empty container and adding just enough blackening solution to cover the parts. I gently agitate the solution till the parts just turn then fill the container with water and drain and continue to rinse with clean water. I then put the parts onto a paper towel to dry. Yes there will be some residual powder but parts can be gently brushed with a soft brush and they will have a dull black/blue sheen.
If you leave the parts in the solution too long, a thick coat will result and this will flake off regardless of how well you prepare the parts.
You can not make brass turn black. Your are only trying to create a patina on the brass, not coat it.
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Just a quick reminder, if you leave parts in the solution too long, it will erode badly or long enough, will completely dissolve.
 
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All great information as I've been a little (VERY!) reluctant to start blackening some parts on my current build. And in my area, distilled water will probably be best. Off to Wally World as I need some for my hobby car's radiator.

Question - has anyone come up with some sort of strainer that these tiny, tiny pats can be laid on so they can be pulled out of the solution at the same time for water wash. Metal doesn't appear to be a good idea. Plastic of some sort, maybe?
 
I found some dry, fine, sand and put the already blackened pieces in a jar. Shook it gently for about 3 minutes. Took them out and wrinsed them off and the black residue is no longer coming off the pieces. And like Peter said, I'm only trying to create a pitina, not paint the pieces. I think they came out pretty good. At least for my first try. Keep track of those tiny pieces, you could easily lose them in the sand.
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Kramer said:
Hey shipbuilders! I have a question about brass blackening for those of you with experience with it. For the brass blackening, does anyone know how long until it's totally set? I've let it sit for 24 hours and it's dry, but still a little chalky and rubs off a bit on my finger. Just curious if it's always going to be chalky and I can handle it now. I'm using Birchwood Casey Brass Blackening. It looks great! Nice and matte, deep black, doesn't look like paint. Very easy process...if I did it right. I soaked the pieces in acetone first for 5 minutes, then dried them off. Put them in a bath of brass blackening which worked immediately.
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Hi Kramer
I hope the attached PDF-file will give you a detailed info about blackening of brass.Personally I use diluted seleniumoxide solution !!!!caution poisonous vapor use it in very good ventilated rooms ,using mask recommended!!!!!
Kind Regards
 

Attachments

  • MetalBlackeningGuide.pdf
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HI KORSHON, I WANT TO EXTEND MY DEEP CONDOLENCES TO YOUR HISTORIC BEAUTIFUL COUNTRY. MAY GOD ACCEPT ALL INTO HIS KINGDOM. GOD BLESS STAY SAFE YOU AND YOURS DON
 
donfarr said:
HI KORSHON, I WANT TO EXTEND MY DEEP CONDOLENCES TO YOUR HISTORIC BEAUTIFUL COUNTRY. MAY GOD ACCEPT ALL INTO HIS KINGDOM. GOD BLESS STAY SAFE YOU AND YOURS DON
Click to expand...
HI DON ,THANK YOU VERY MUCH FOR YOUR DEEPEST SYMPATHY AND COMPASSION FOR ALL AND FOR MY COUNTRY , MY FRIEND.
WISH YOU ALL THE BEST,TAKE GOOD CARE OF YOURSELF AND GOD BLESS YOU.
 
pour ma part :
dilution 20% (1+4 eau)
durée : 2 à 3 minutes dans le bain
puis séchage + lustrage au chiffon doux

Je répette l'opération 3 à 4 fois jusqu'à atteindre le noircissement voulu , puis rinçage à l'eau
pour finir , frotter au chiffon huilé pour un aspect satiné


for my part :
dilution 20% (1+4 water)
duration: 2 to 3 minutes in the bath
then drying + buffing with a soft cloth

I repeat the operation 3 to 4 times until I reach the desired darkening, then rinse with water
to finish, rub with an oiled cloth for a satin appearance
 
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