anodizing for beginners

T

ThirdTooth

Joined
Mar 21, 2012
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I expected to find a lot of great tips on this online but I was actually pretty disappointed. if this is a thread thats been made a million times try t be merciful XP

what does a beginner need to know for this? as I understand you just blast your metalic target with a propane tourch and it'll give you funky rainbows of color. what are the subtitles of it though? does the same approach work for both titanium and regular steels? is it easy to damage hardware this way? whats the best way to set things up (what with dealing with flames and hot steel and all).

Its for a gift I'm making so I need to make sure I do it right.
I plan on anodizing the hardware and liners on a knife (not the blade though)

thanks!
 
That is heat coloring. Anodizing is a totally different process.
Heating steel changes it's hardness-usually making it softer.
 
Flame colouring or heating is not anodizing.. Anodizing invloves an electrical power source, an acid bath, acid circulation, ventilation, and respiratory filters and a cathode, along with the parts to be coated which act as the anode... (hence anodizing...) The colours generally are a dye that fills the pores of the coating that is created in the anodizing process.

Thick type III can have its own greyish-greenish-blackish colour, but it requires still more hardware (chillers) and time... If you want to pursue this let me know and I can provide more info, as I have some experience with small scale production of Type III anodizing.

Flame colouring is much easier and faster.
 
Rapt_up said:
Flame colouring or heating is not anodizing.. Anodizing invloves an electrical power source, an acid bath, acid circulation, ventilation, and respiratory filters and a cathode, along with the parts to be coated which act as the anode... (hence anodizing...) The colours generally are a dye that fills the pores of the coating that is created in the anodizing process.

Thick type III can have its own greyish-greenish-blackish colour, but it requires still more hardware (chillers) and time... If you want to pursue this let me know and I can provide more info, as I have some experience with small scale production of Type III anodizing.

Flame colouring is much easier and faster.
Click to expand...

Hmm can you give me some more details? I think anodizing looks awesome, as does heat/flame coloring. I have no experience with any of it though and I'm wondering if it is extremely difficult, expensive, time consuming, etc.
 
dust. said:
Hmm can you give me some more details? I think anodizing looks awesome, as does heat/flame coloring. I have no experience with any of it though and I'm wondering if it is extremely difficult, expensive, time consuming, etc.
Click to expand...

I second this request! I'm curious if I can change my Benchmade 940's purple titanium backspacer to blue?
 
I'm less familliar with Ti anodizing, I was talking more about Al anodizing, but the principles are the same, with the exception that the colours are the result of the thickness of the anodized coating with Ti. So its more critical that you have the variables in control if you want specific and consistent results.

First off, its dangerous to your health, you are dealing with an acid bath, and you are running electricity through it. You can cause all sorts of dangerous and un healthy situations. What I describe is in no way exhaustive or "safe", anything you do is taking responsibility for your own safety or lack of it.

With Ti I've heard that virtually any acid solution will allow you to anodize it. There is even info on the web about using cola, and the colour and thickness are controlled by your voltage. The larger the surface area to be anodized the more current you will need.

With Aluminum the best choice is sulphuric (battery) acid, and current and voltage are related to rate of finish buildup, and both thickness and pore size which affect hardness. Also temperature increases with higher current and can cause some vapourization of the acid, as can agitation to avoid bubble formation and which may produce acid mist. All of which are dangerous, the fumes/mist may not be visible and inhalation WILL damage your lungs. You may not even be aware of it at the time since your lungs lack nerve endings so there is no sensation. Respirators and ful protection (gloves aprons, splashproof goggles etc) are all bare minimums with sulphuric acid.

The basic principle is you connect the part to an electrical lead and suspend it in the acid bath the other electrical lead makes contact with a "sacrificial cathode" to complete the circuit. Then you run current/voltage through the part and the bath until your desired level of coating is complete. .Once complete the electricity is shut off, the part removed and cleaned/neutralized. If its Aluminum it will be dyed and sealed. And cleaned again. Except type III (Which is military hardcoat, which is usually self coloured and must be done at temperatures near freezing. Typically it will be cleaned neutrralized after anodizing and either just sealed, or lubricated and sealed.

resources for materials can be found at Caswell Plating. They have lots of supplies for all sorts of finishing processes.
 
Titanium anodizing is completely different than with aluminum. Aluminum uses acid, dye and voltage. Titanium colors are from refraction of light through an oxide layer, the thickness of the layer determines the color. This can be achieved either with heat or with a variable DC voltage supply. Acid is not needed, any electrolyte will work, I use TSP. Stainless can be heat colored. Nice technical article on the science behind titanium colors here: HERE (not my website)
 
Bill DeShivs said:
That is heat coloring. Anodizing is a totally different process.
Heating steel changes it's hardness-usually making it softer.
Click to expand...

Bill I was wondering if I take a pocket clip which is satin or polished can I take a propane torch and heat it to a color I like? If I get to the point where I like the color do I simply let it cool off at that point or is there more to it than that?
 
Glad someone with more Titanium experience could comment here too since that seems to be more where people are interested.
:thumbup:
PSD said:
Titanium anodizing is completely different than with aluminum. Aluminum uses acid, dye and voltage. Titanium colors are from refraction of light through an oxide layer, the thickness of the layer determines the color. This can be achieved either with heat or with a variable DC voltage supply. Acid is not needed, any electrolyte will work, I use TSP. Stainless can be heat colored. Nice technical article on the science behind titanium colors here: HERE (not my website)
Click to expand...
 
MTHall720 said:
Bill I was wondering if I take a pocket clip which is satin or polished can I take a propane torch and heat it to a color I like? If I get to the point where I like the color do I simply let it cool off at that point or is there more to it than that?
Click to expand...

That's all there is to it, except it may destroy the temper, and the colors are not durable.
Stainless colors are not as pronounced as carbon steel, but most stainless heat treating is not as heat sensitive as carbon steel.
 
PSD said:
Titanium anodizing is completely different than with aluminum. Aluminum uses acid, dye and voltage. Titanium colors are from refraction of light through an oxide layer, the thickness of the layer determines the color. This can be achieved either with heat or with a variable DC voltage supply. Acid is not needed, any electrolyte will work, I use TSP. Stainless can be heat colored. Nice technical article on the science behind titanium colors here: HERE (not my website)
Click to expand...

Thanks, that is very helpful! Just one more question for the experts... Is the only way to remove a color anodizing from titanium to sand down the oxidized layer? Going back to the BM 940's purple back spacer, since it is a "higher" level of anodizing than blue, do I have to remove it before I can add a blue anodizing? Or, is it not possible to change to a lower spectrum color?
 
I guess in theory you could change a lower voltage color to a higher voltage color without stripping off the color first but you might not get the results you are looking for. The surface would have to be completely oil free, also the color you are trying to change may be heat colored. I have no idea what would happen to a heat colored titanium if you tried to anodize it further. It is possible to strip off an anodized color without sanding by using a product called MULTI ETCH. This stuff is pretty toxic and needs to be used with great care. It is a surface prep for anodizing but will also 'dissolve' off an unwanted color. In addition to removing the color it will also turn the titanium dark grey and even make the surface a little matte, depends on solution temperature and exposure time.
 
PSD said:
I guess in theory you could change a lower voltage color to a higher voltage color without stripping off the color first but you might not get the results you are looking for. The surface would have to be completely oil free, also the color you are trying to change may be heat colored. I have no idea what would happen to a heat colored titanium if you tried to anodize it further. It is possible to strip off an anodized color without sanding by using a product called MULTI ETCH. This stuff is pretty toxic and needs to be used with great care. It is a surface prep for anodizing but will also 'dissolve' off an unwanted color. In addition to removing the color it will also turn the titanium dark grey and even make the surface a little matte, depends on solution temperature and exposure time.
Click to expand...

Thanks for all of you advice! Sorry, I forgot about this thread for a couple days... It's nice to know that knowledgeable people are replying even if us newbies get distracted.

I'll have to look into multi etch if I start to mod my Benchmade 940... Thanks PSD!
 
Wish I were set up to do this kind of thing. I will just stick with heat coloring of pocket clips which I first thought was called flame anodizing.
 
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