Anodizing Dye pH

[mcaswell ******* Inc Founder Find all posts View Profile Close mcaswell]

DYES OPTIMUM Ph

RED BORDEAUX 6

YELLOW 4A 6

BLUE 4 A 6


VIOLET 3D 6


BLACK HBL 5.5


GREEN SCG 6.6


GOLD S 6


TURQUOISE 5.5


OLIVE DRAB 7.5


GOLDEN ORANGE 7


GREY BL 5.5


BROWN GL 6.5


TEAL 5.5


ELECTRIC BLUE 6


COPPER BF 7


FLOURESCENT PINK unk

BRONZE 5.5



DEEP RED 5.5


FLOURESCENT YELLOW 6


GREEN AEN 6


VIOLET DS 6


GREY NLN 5.5


YELLOW 3GL 6


BROWN BL 6.5


FAST BLUE 5.5


ORANGE 3A 6

[blackcote Amateur Metal Finisher Find all posts View Profile Close blackcote]

Re: Anodizing Dye pH

I had to search around to find how to adjust the ph and I'd thought I'd save someone else the trouble and post a link to it. Enjoy.
http://forum.caswellplating.com/show...6387#post16387

[acidcustom New User Find all posts View Profile Close acidcustom]

Re: Anodizing Dye pH

pH for fluro pink is 5.5-6 got it from tech support today

john

[GG Engineering New User Find all posts View Profile Close GG Engineering]

Re: Anodizing Dye pH

I got a electronic PH tester. Do I put it into the black dye directly to measure the PH when the solution is cold or hot? I'm afraid the black dye is going to discolor the PH tester because it yellow plastic.

[anodizeworld New User Find all posts View Profile Close anodizeworld]

Re: Anodizing Dye pH

The plastic ph testers work well. Calibrate first. Cold Dye. Adding dye will usually raise the ph. Sometimes if ph is too high the dye won't absorb properly. We had problems with reds because of high ph in the past.

[brwn253 New User Find all posts View Profile Close brwn253]

Hey guys,

I was wondering if just "ph up" (Sodium Carbonate, Soda Ash) and "ph down" (Sodium Bisulfate) from a store would work for altering ph levels in the dyes? Or are acids necessary?

Thanks!

[Caswellplating_Jason Moderator Find all posts View Profile Close Caswellplating_Jason]

Hi Brwn253,
To raise the PH, you will need to use Sodium Hydroxide, to lower the PH, use Acetic Acid.

[Brt123 New User Find all posts View Profile Close Brt123]

Hi Brwn253,
To raise the PH, you will need to use Sodium Hydroxide, to lower the PH, use Acetic Acid.

Hi Jason,

Does the Acetic Acid need to be 99.85% can we get away with a Certified Food Grade - High Purity Ethanoic Acid at a lower grade ?
https://www.ebay.co.uk/itm/500ml-Ace...d/131775286037

Sodium Hydroxide With a purity of over 99.4% Supplied in micro prill form. be ok mixed with Distilled water ?
https://www.ebay.co.uk/itm/750g-Sodi...c/143537134686

Thanks

[KevinB Amateur Metal Finisher Find all posts View Profile Close KevinB]

It doesn't matter where you get the acid or base from, nor does it matter what the initial concentration is. What matters is that 1) it doesn't have anything else in it (i.e. it's fairly pure), and 2) you know what concentration you are starting from so you can calculate the add quantity.

Even if you don't know #2, you can still make it work by making small adds and checking the bath pH after each add.