Adding color to aluminum by anodizing

[John K Jordan]

I've been reading about electrolysis anodization of aluminum to add color and increase surface hardness. I'd like to try turning some aluminum items on the wood lathe and adding color after turning. I'm considering small items perhaps an inch or so in diameter and a bit longer.

Has anyone tried this? I've read about voltages schedules and such. Any suggested references for practical information/instructions, amperage, chemicals? Is acid etching needed? I have variable voltage DC power sources.

JKJ

 

[Gregory Hickman]

I have variable voltage DC power sources

Everything I've read about home anodizing, suggest this is very helpful. I've not done this myself, but the process isn't rocket science. Controlling your voltage and your times would create a very repeatable result. I'm looking forward to your results, às I'm interested in this myself.

Gregory

 

[Doug Rasmussen]

Everything I've read about home anodizing, suggest this is very helpful. I've not done this myself, but the process isn't rocket science. Controlling your voltage and your times would create a very repeatable result. I'm looking forward to your results, às I'm interested in this myself.

Home anodizing???? In theory, yes, but the professionals can't even get it right. Anodizing has been a nightmare for shops like mine. Repeatable results, no, colors from one batch to another don't match. If the color is wrong to redo an acid etch is done which destroys shiny machined surfaces. Anodizers frequently ruin parts.

Hard anodizing is a process that gives a very hard protective surface, it's hardness is easily noticeable in machining hard anodized parts. I don't know that it can be done at home. Color anodizing is a much simpler process. But the color is not permanent or protective, various household products like Easy Off oven cleaner will remove color anodizing.

 

[Bryan Field]

I've done a few anodized pens on the wood lathe. The process is complex and results vary. I used a variable supply as you need to adjust it as you are setting up. Cleanliness is everything!
Brad Gothard has some excellent YouTube's on the process.
If you DM me, I can send you his PDF "How to Anodize at Home"

 

[Kent Reisdorph]

I can't give you any recent experience. When I was in college I worked for a place that made racquetball racquets. I went to the anodizing shop and watched the process. I know they started with an acid bath, but that's about all I can tell you.

 

[robo hippy]

I know anodizing is done to prevent the aluminum from "oxidizing". This is critical to aviation manufacturing. Not sure about the exact process, but along with the acid bath, I think it involves electricity, maybe remotely related to galvanizing.

robo hippy

 

[Bill Alston]

I looked into this many years ago. Choosing the correct type of aluminium alloy and using proper dyes were the major points I learned. It all sounded a but long winded in the end so I didn’t pursue it any further. I’ve seen some wonderful patterns produced by anodising using wax resists though if that’s the correct term?

I made quite a few parts maybe 20 years ago that needed anodising, the cost was very reasonable and the results exactly what I wanted. I didn’t specifically ask for it but they “Hard Anodised” them. This is done at sub zero temperatures and produces a much thicker, more durable oxide layer.