De-anodize frame

[Anders Kolpen]

Hello in the group 

I've seen some of the fantastic 'raw' work people do here on TF to de-anodize parts and frames

 

I have a anodized frame that I want to raw. 

 

I've de-anodized a couple of small parts in small containers with luck, but a not a whole frame. 

 

Would you mind sharing some tips for a good result on large items? 

 

Like, does the frame have to be fully submerged in the bath or can I like, do half'n half without any transition in the final finish in a smaller container? 

 

What ratio/concentration did you find works best for caustic soda/water? And also would you recommend hot water? 

And also, would actually suggest oven cleaner instead of caustic soda solution? 

 

 

Thank you very much for any help on this one! 

 

Greetings from Denmark 

 

Anders Kolpen 

[Julius Czar]

The only experience I've had with this was a few smaller components, headset, cranks etc.

I used an oven cleaner solution with hot water and left it for around 20 minutes, checking on it periodically. It removed the anodising from the parts completely, even in the hard to reach places. 

As for quantity I used roughly 50ml in 1L of hot water, but I suppose you could add more if it's not effective enough. I cant see it causing any issues as long as you remove it as soon as it's free of the colour and rinse it thoroughly afterwards. It will start to etch the aluminium if left too long!

As I said I haven't done anything as big as a frame, but I'd personally recommend getting a big enough container to fully submerge it and turning it over periodically to ensure the solution is getting all of the frame.

[craigjames]

Caustic soda is whats in over cleaner and removes anodising from Aluminium. You need to be careful with it, it's nasty stuff, so glasses, long sleeves and gloves are a good idea. Also you need to protect any threads on the Frame as it can and will eat away at them if you leave the frame in it for too long.

Bear in mind that once you've removed the anodising the aluminium will oxidise and go dull reasonably quickly

[Jere_h]

I've stripped multiple things with pipe opener, such as Trialtech rims and a front hub. Clear coated with acrylic after that. It's really easy, but your object is quite large so avoid breathing the vapors too much. It's really nasty smelling stuff and starts to burn in your lungs pretty quickly. Probably not very healthy, recommend doing it outdoors.

No need to submerge, a large paint brush works well for spreading the chemical over the surface and rubbing the color away. Very easy to control it that way so it won't eat the alloy too much. You typically need to repeat the "painting" process few times until all the color is gone.