Diy Ti annodising

[02GF74]

I'm after some long M5 Ti bolts which unfortunately are available in multi coloured.

Annodising to change looks pretty simple. , alkaline solution and power supply (i got bench power supply, +/-30v so should do)

I've looked online and colour is precisely controlled by voltage.
I'm looking to change them to be blue.
Has anyone tried it?

[Mackers]

A few years ago there was an sizeable topic about exactly this subject.

[Vertigo Cycles]

Blue is ~25-30V and will shift from dark to light as you go through the voltage.

[02GF74]

Yes, I did it. Had to use fine wet and dry to remove the oxide first. Came out a pale blue, was hoping for stronger colour but at least no longer multicoloured

[Carcinogent]

One thing that needs to be mentioned is that you need to test *your* particular conditions. Ie 25-30v is blue though it depends on the strength of your solution, so it might be 23-28v for example. Ti builders (Firefly) test on a scrap ti tube to get a 'spectrum' for precise calibration of their conditions. Of course it depends on how fussy are you and what your final goal is. For just a couple of bolts you might just need a ballpark voltage range. =)

[02GF74]

I got a psu with variable voltage, started off low and once I was happy with the blue colour I stopped.