anodizing a design
May 10, 2005 7:11 AM Subscribe
I saw a neat clock the other day on MoCoLoco and I was wondering process is used to get the design printed/dyed on the face. It says that it's anodized, and from my research this seems pretty straightforward, but my question is how is the printing/masking done? Are the dyes added in stages using a photomask? Or is it masked in the anodizing stage? You can see a good example of the colors here
When you anodize aluminum you pop it in a bath of acid and run electricity through it that causes the aluminum to corrode and become coated in aluminum oxide; which is porous. You then pop it in a cold bath of dye to color it, and seal it by popping it in hot water. The part I don't get is how you go about masking it so you can get a cool design on it like the clock face with multiple dyes (could you silkscreen it after anodizing?) Apologies for the rambling :)
When you anodize aluminum you pop it in a bath of acid and run electricity through it that causes the aluminum to corrode and become coated in aluminum oxide; which is porous. You then pop it in a cold bath of dye to color it, and seal it by popping it in hot water. The part I don't get is how you go about masking it so you can get a cool design on it like the clock face with multiple dyes (could you silkscreen it after anodizing?) Apologies for the rambling :)
Response by poster: I see. How long does the surface remain porous after anodizing, days, weeks, longer? Does it just remain porous indefinitely? As a side question what kind of business would do this kind of work, and any idea of the approximate costs?
posted by zeoslap at 8:19 AM on May 10, 2005
posted by zeoslap at 8:19 AM on May 10, 2005
Response by poster: The plan is to make myself something similar. With regards anodizing from what I've read the dye itself isn't bonded to the metal, the anodizing process just leaves a porous surface of aluminum oxide on the metal a few microns thick which can then be dyed. My best guess at the mo is that they anodize the whole sheet and then silkscreen the three colors of the design onto it.
posted by zeoslap at 1:16 PM on May 10, 2005
posted by zeoslap at 1:16 PM on May 10, 2005
Best answer: You are correct in assuming that the aluminum is anodized and then has the graphics silkscreened onto it. Doing it any other way would be prohibitively expensive, and to get a consistent finish, the masking would have to be removed, and the OPPOSITE areas masked, and the rest would be clear anodized. That's definitely not what they're doing. In fact, the whole thing may not be aluminum at all- there are many paints for steel that closely resemble aluminum. (Though that's unlikely.)
I can help you locate a company to get the metal anodized if you like, email is in profile. (I run a machine shop.)
posted by wzcx at 2:03 PM on May 10, 2005
I can help you locate a company to get the metal anodized if you like, email is in profile. (I run a machine shop.)
posted by wzcx at 2:03 PM on May 10, 2005
Anodize is generally used to protect aluminum from oxidizing, either because of the environment or because of a galvanic corrosion.
You can have different types and thickness of anodize. There is one anodize material (Tuff-Ram I think it is called) that is teflon impregnated to provide a very hard surface that has a low coefficient of friction. This is used in sliding parts like valves.
Like wzcx said, any machine shop will know how to get this done. Your best bet from a business standpoint would be to get the machine shop to do all of the processes. You don't want to get involved in the transfer of parts between the processes, and the machine shop will know who they work with best.
You can get anodize in many colors. If you look at bicycle parts with bright colors, like electric blue or even pink, those are anodized parts.
Another process that is used to protect aluminum is chem-film or chemical conversion coat. This is a very think film that is applied to aluminum from a bath dip. This protects a little, but also allows for electrical conductivity across the surfaces.
What surface finish are you aiming for? Do you want it to look metallic, painted, coated, bare? Many people assume that aluminum wont corrode. Those people are wrong.
posted by jonah at 3:37 PM on May 10, 2005
You can have different types and thickness of anodize. There is one anodize material (Tuff-Ram I think it is called) that is teflon impregnated to provide a very hard surface that has a low coefficient of friction. This is used in sliding parts like valves.
Like wzcx said, any machine shop will know how to get this done. Your best bet from a business standpoint would be to get the machine shop to do all of the processes. You don't want to get involved in the transfer of parts between the processes, and the machine shop will know who they work with best.
You can get anodize in many colors. If you look at bicycle parts with bright colors, like electric blue or even pink, those are anodized parts.
Another process that is used to protect aluminum is chem-film or chemical conversion coat. This is a very think film that is applied to aluminum from a bath dip. This protects a little, but also allows for electrical conductivity across the surfaces.
What surface finish are you aiming for? Do you want it to look metallic, painted, coated, bare? Many people assume that aluminum wont corrode. Those people are wrong.
posted by jonah at 3:37 PM on May 10, 2005
Another (much cheaper) way to do it is to have it printed on transparent adhesive vinyl. This is how a lot of metal storefront signs and car decals are created. Think of it as a piece of advertising and talk to a signwriting company
posted by -harlequin- at 1:29 AM on May 11, 2005
posted by -harlequin- at 1:29 AM on May 11, 2005
This thread is closed to new comments.
You can easily stencil anodized surfaces using an airbrush and the correct ink/paint. This is my guess though, I'm not 100%.
posted by jonah at 7:42 AM on May 10, 2005