I've recently been approached by a few people asking for advice on how to remove the anodizing from the Cobalt in places that it's important to do so. So, I will post a detailed instruction guide on how I do it with pictures.
Before I post the how to here is a list of things you will need and might want to get.
100% Lye drain cleaner (
http://www.truevalue.com/product/Rooto-Crystals-of-100-Lye-Household-Drain-Opener-1-lb/14320.uts
Standard Rubber cement (
http://www.amazon.com/s?ie=UTF8&page=1&rh=n:12900041 )
Eye dropper or pipette (
http://www.walgreens.com/store/c/walgreens-eye/ear-dropper/ID=prod6002858-product ) (
http://wizardlabs.us/index.php?route=product/product&filter_name=pipette&product_id=98 )
Toothbrush or any soft brush
Lapping compound for Valves (
http://www.autozone.com/autozone/ac...-Compound/_/N-2592?itemIdentifier=526806_0_0_ )
First off let me say that Lye when mixed is incredibly caustic and will burn your skin, so you may want to use rubber gloves during this. Since it is so caustic, it will eat the anodizing off your device pretty quickly. It heats up when added to water because of an exothermic reaction so also be cautious that you don't burn yourself.
Mix 1-2 tbs of lye crystals into 1 cup of warm water. (this stuff works better when it's hot) Mix thoroughly to make sure there are no crystals clumped on the bottom.
You may want to "mask" the anodizing you DON'T want to be removed with the rubber cement. If you have steady hands and believe that you can control the liquid from going where you DON'T want it, you can skip this step. place the rubber cement right on the metal and allow it to dry. You may want to apply several layers until it's thick. This will make removal so much easier as it will just "peel" right off.
Fill your dropper or pipette with lye from the cup and apply the solution to the atty deck in the negative screw hole. You will only want 1 drop because it will NOT go down into the hole all the way unless you use a hypodermic to spray it down into the very bottom. Take care this stuff produces hydrogen gas when it eats away the aluminum and will bubble and cause the stuff to spread droplets of lye around. (it's why I recommend masking with the rubber cement.) You do not want to just get it in the hole. You also want it to remove the anodizing directly UNDER the screw head itself. You want the coil to touch as much exposed aluminum as possible.
Now, it may LOOK like this has already been done to your unit, and you can verify if it's down to metal by quickly scraping over it with your xacto knife. I've yet to meet a Cobalt that had truly had all the anodizing removed here. I may look removed, but it's not 100% gone most of the time.
You can use a xacto knife or something flat to scrape away the dye and anodized layer as it's working to facilitate this going faster. It should only take 2-3 minutes. You'll know when your successful when you can lightly scratch the aluminum and actually see the scratch. Anodized layer is hard to scratch when light pressure is applied. Rinse THOROUGHLY with water when done. Use a toothbrush to remove any smut layer (light or dark grey metal) When your done, apply a little dab of grinding compound to the threads with a toothpick and work the screw in and out until the screw has sanded away any smut or anodizing left inside. Rinse with hot soapy water as best you can. You may also try denatured alcohol or other solvents to truly remove the grinding compound.
Move next to the inside of the battery area. You have 2 options available to you in doing this. You can FILL entirely the tube up to the top of the tube, or you can apply the lye only to the threaded area. The only place it's IMPORTANT that it go, is the threaded area. if you apply it with a dropper onto the threads, slowly turn the tube to allow the solution to sit in the threads and eat away at the anodizing. When you are done (again it should only take 2-3 minutes) immediately rinse with tap water and use your toothbrush to remove any smut as you rinse. You'll want to take a incredibly small dab of valve grinding fluid and using a q-tip place it in the threaded area in one small dot. (1/8" dot is more than enough) Thread the tailcap on and slowly work it back and forth until it can thread all the way on. This material actually contains an abrasive and will sand down the threads so that you have true bare metal on the threads. When your done with the valve compound, rinse it clean with soap and water and your toothbrush.
Should look like this when your done.
Next take apart the switch assembly and mask this sucker. I HIGHLY advise you mask this or you most likely will spill it where you don't want it. Here is a picture of where I stripped and any place that is STILL blue needs to be masked with rubber cement.
Apply the lye solution until it fills the entire bottom of the switch spring area and the screw area. Allow it to work and rinse away any remaining smut with a toothbrush when done. When you are done with that, hold the post into the cup of lye and allow the remainder of teh anodizing to be removed from the side of the post. May take a few minutes of patience for it to work. Again brush and rinse. Now you've removed all the anodizing from the vital areas and we are going to again apply a little grinding compount to a Q-tip and put it down into the spring resting area and spin our Q-tip around the bottom using the Q-tip as the "sandpaper" that we ordinarily wouldn't be able to fit down in this area. You can also use it to sand down the top of the side of the switch. Any place you removed anodizing can use the compound to sand it back down past any smut layer that may remain from the lye. When you are done grinding rinse with soap and water and a toothbrush and reassemble everything and vape happily knowing you've done everything in your power to make sure that your anodizing is gone and where it's not supposed to be!
I hope that this helps everyone get their Cobalts working 100% as they truly are an incredibly beautiful PV.