In this Instructable, learn how to anodize titanium objects at home. The process is fairly quick and simple, but you will need to do a little legwork to get the right supplies before you can start.
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Step 1: Gather Supplies
1. Power Supply: In order to have full control of the voltage, we used a 120V power supply from Amazon :
You can use regular 9V household batteries for your power supply, but you will be limited to using voltages in increments of 9V and you will miss some of the colors available on the anodizing spectrum. Overall, we felt that using the power supply was safer and easier to control.
2. Alligator Clip Leads: You need one for positive flow and one for negative flow. We used these: http://www.amazon.com/Elenco-Electronics-TL-16-Ban...
3. Trisodium Phosphate: Will be referred to as TSP. Similar to dishwashing detergent. A little goes a very long way, so this $4 box will last you forever :http://www.amazon.com/Savogran-10621-Trisodium-Pho...
4. Titanium Sheet: This is one of the harder items to locate. Basically, in addition to the titanium object which you wish to anodize, you will need another titanium object that has more surface area than the original object. It doesn't have to be a sheet. Actually, if you are going to anodize something small (like a ring) you can substitute a large amount of wadded up titanium wire for the titanium sheet as long as it has more surface area than the ring. The object you wish to anodize (in our case a ring or a spork) will serve as the anode, and the other titanium object with more surface area (in this case a titanium sheet or wadded up wire) will serve as the cathode. The both of the titanium objects will need to fit in your large bin (item #6).
5. Titanium Wire: Again, a little goes a long way. You will probably only need about a foot of this wire if you also have the sheet (item #4) and you will be able to re-use it infinitely. Make sure it is 100% titanium like this one :http://www.amazon.com/Pure-Titanium-Round-Resistan...
While shopping, we learned that this product is also popular for vaping?
6. Large Plastic Bin: You will need the bin to be large enough to hold your titanium sheet, your titanium object for anodizing, and enough water to fully submerge your object to be anodized. We used this kitchen scale for measuring water and Trisodium Phosphate, but it is not strictly necessary. We used this biohazard bin that was lying around ;)
7. Isopropyl Alcohol: For cleaning the object you want to anodize. Not strictly necessary, but will yield better results. Should cost about $2 at your drugstore.
8. Titanium object to Anodize: This is the fun part. If you are going to go through all of these steps, I suggest that you have a variety of titanium objects on hand to make the most of your setup efforts. The important part is that the object by 100% titanium. We experimented with a few that were clearly not truly 100% titanium and it isn't necessarily dangerous, it just won't look as good. I ordered my Spork here: http://www.amazon.com/Light-My-Fire-Titanium-Spork...
We also tried some rings, cuff links, and a camping mug (didn't work well)
Additional household supplies:
Small plastic cup
Newspaper (for covering the table)
Step 2: Prepare Your Supplies
Cover your surface in newspaper if you like.
In order to fill your plastic bin with the correct water/TSP ratio, follow this rule : 5g TSP / Liter of water
Since a liter of water weighs 1000g, we zeroed the scale with the bin on it (NOT PICTURED) and then added 3000g of water (3 liters). We then zeroed the scale with a smaller cup on it (NOT PICTURED) and then added 15g of TSP.
We then used a plastic spoon to mix the 3000g of water with the 15g of TSP.
Step 3: Prepare Your Circuit
Put your titanium sheet into your plastic bin. As you can see, the water line on my titanium sheet shows that the titanium is about half submerged. The submerged part must have a surface area greater than the object you will anodize. If it is not bigger, make more solution of water and TSP so that the titanium sheet will be further submerged in the solution. If the ends of your alligator clip leads are not titanium (ours aren't) then you want to make sure that there is enough of the sheet sticking out of the water for the clip to attach onto without getting wet.
Once the sheet is in the bin, connect your leads to the power source. The power source should be OFF at this point for safety.
Next, connect the alligator clip lead attached to the NEGATIVE output of the power source to your titanium sheet. This will be the CATHODE.
Step 4: Prepare Your Item for Anodization
Wipe down your object with the isopropyl alcohol to clean it if you like.
Next, wrap the titanium wire around your object a couple of times. You need the titanium wire to be wrapped enough to form a secure hold on the spork and a solid electrical connection. You want enough wire left over to create a "handle"
Attach the remaining wire to the alligator clip connected to the power supply's positive output
Step 5: Now for the Fun Part!
Once your leads are all set up, it's time to turn on the Power Supply and start anodizing.
The basic overview: You will be turning on the power supply, dipping your object into the solution, adjusting the voltage, and checking to see what color your titanium has turned. The important thing here is that you need to know that the ANODE SHOULD NEVER TOUCH THE CATHODE. This means that the spork should never touch the titanium sheet. If you do this, you will form an arc and short the circuit. With low voltage, it won't hurt anyone, but the higher your turn up the knob, the more dangerous the potential for harm. So BE CAREFUL and LEAVE SPACE.
The space I am referring to is demonstrated in the first picture on this step.
Put on a pair of safety gloves (a good idea) and grab the positive lead. Holding the end of the lead, slowly dip the spork into the tub of water until it is completely submerged (as seen in the second photo). Turn up the power supply in intervals of 5V or 10V and wait a few seconds at each interval. Check the color of your spork after each change in voltage.
Since we are amateurs, we were mostly experimenting with the correct # of volts to create our desired colors of anodization. There are many websites with varying graphics of the relationship between the volts and the colors produced. I like the one at the bottom of this page: Mr. Titanium . Most sources say you won't get much color change until about 20-25V. The important thing to know here is that you cannot reverse the anodizing. If you anodize at 50V, you will never be able to return to the colors produced at 40V, so go slowly.
Step 6: Keep Experimenting
You probably won't get the desired result on the first try. After multiple attempts, here are some pictures of what we anodized during this session.
You will get variance in color based on the finish on your object (hammered, sandblasted, shiny, etc.) and other variance based on the purity of the titanium. You will discover that many titanium products you buy online doesn't end up being 100% titanium and the anodization will look wonky.
PS Wash off your utensils before using them :P