anodized metal

I was wondering, what exactly is anodizing?

From Wikipedia

It’s a surface treatment that protects the metal and can also give it nice colors. It’s more durable than paint. Typically done on aluminum alloy parts. I don’t believe you can anodize steel.

is it expensive to have done, and how does it last compared to a powdercoat?

It can be expensive, or it can be cheap. Depends on the type of anodizing and where you get it done. If you can get it done with another batch of parts it can be cheaper, but then you’ll be limited in color choices.

It also depends on what you’re getting anodized. If you’re anodizing an entire frame it is going to be more expensive in part because they’ll need a larger tub to dip it in. Small parts are cheaper and more convenient to do, and some you can even do yourself at home.

I’m not sure of what kind of price range to expect.

What do you want to anodize?

how does one go about annodizing at home? (without burning down the house or voiding the warranty on just about everything in the house)

a rim.

a 19" rim.

Proper anodizing at home is a little involved. It requires a DC electric charge from something like a car battery charger and chemicals like sulphuric acid. It’s a full blown potentially dangerous chemistry lab experiment at home. Google for something like “DIY anodizing” or “home anodizing”.

The more practical way to do it at home is chemical etching. It’s not anodizing. However, it’s more convenient to do at home than proper anodizing. You don’t need the DC current, but you still need some potentially nasty chemicals. I’m not sure what this method is called so Googling for a DIY guide is a little difficult. It’s all a chemical process, no electricity involved, so more practical to do at home. Colors are not going to be the same as for proper anodizing. And chemical etching actually removes material so will not be appropriate for all parts.

Talk to local machine shops and plating shops. See what they suggest or what they can do. I don’t know what kind of ballpark price you can expect for something like that.

Anodising involves putting aluminium in an electrolyte bath (acid) with a DC current running through it. The part becomes the anode of the electricity supply, hence the name. What happens is, the electricity causes the surface of the metal to oxidise. This oxidisation is porous so if you want colour (which is mostly the point of it but it’s not necessary) the piece can then be put into a dye bath and the pores are then sealed to retain the colour. It’s not as hard to do at home as you may think as long as you’ve done your research. You need a power supply that can be had from ebay, wire, some battery acid will work for the electrolyte, a couple of chemical resistant tubs, and the dye. Not any old dye will work. The right ones can be found at a website i’ll get for you but certain RIT fabric dyes will work although the colours are limited.

Titanium, Niobium and Zirconium can also be anodised and are slightly easier since they don’t require dye. They just require a variable voltage in acid to create different thickness oxide layers which changes the refraction properties.

The best websites I know of are:
http://www.focuser.com/atm/anodize/anodize99.html
http://www.caswellplating.com/ (this place has all the dyes and a good forum to ask questions)
If you’re interested, http://mrtitanium.com/ has some info on titanium and instructions on how to build an anodiser (it wont work for aluminium though since they require different voltages and amperages).

I might be able to help out if you’ve got specific questions but i’m by no means an expert.

Siege

i’ve got a 5 litre tub of sulfuric acid in the shed.
i’ve got a 12 volt charger i can use.
i’ve got buckets and whats not.

i dont have dye for it.
i dont have anything to annodize.

i really want to annodize something but i havent got anything DAMNIT what can i use thats aluminium?

try aluminium. what about buying some metal, make something creative and then do it

thats no fun, i need to do something i’ve already got. hmmmm.

Do you have a bike with aluminium brake levers? Or a Magura, the levers on them are aluminium.

It would be more fun to buy some aluminium and make something though, like a seatpost clamp or something.

I might try this to anodise some stuff for my car!

Rock on!
Edd

you have a 5 litre tub of sulfuric acid? why?

i’m not sure why we’ve got it. but it was funny, i put it in the shed next to the tub of chlorine which is next to the bag of fertilizer. dad was like “shit i hope the cops dont see this they’ll think we’re friggen terrorists”

you gotta be the worlds lamest terrorist

You can make a pretty good bomb with some fertilizer and other household ingredients (not mentioning them here for safety’s sake). throw in some sulfuric acid and it becomes even more dangerous…

Timothy McVeigh made a pretty devastating bomb(s) from easily-obtainable supplies - I wouldn’t call him an especially ‘lame’ terrorist.

hey guys, is it possible to annodize some aluminium with HCl instead of sulfuric acid??

you could do my nimbu’s cranks (but if you srew it up then :angry: BAM)