[One (M7) General] Crackanug:
THE STORY:

Since I bought this phone I wanted to do something to the back cover, I just wasn't sure what. Plus I wasn't really set on the idea of doing something to risk damaging a perfectly good (and new at the time) phone. That was until about 2 months ago when I managed to put a small hairline crack in the digitizer. Since the phone was no longer undamaged, yet still 100% functional, I figured why the hell not customize it.

I read awhile ago on XDA about some users discussing what the phone would look like with a polished look but no one was willing to take the plunge. This seemed like a good/fun project now that I didn't care if I screwed it up.

First I used 1000 grit wet/dry sandpaper to remove the anodization. While this method was working, it was painstakingly slow to get to bare metal. The interesting thing about 1000 grit though, it doesn't remove the anodizing right away yet takes out a lot of the minor blemishes due to everyday use. This could in turn be used carefully to remove any dings you have without removing the anodizing. In this photo it is hard to see, but the top half near the camera hasn't been sanded, while near the HTC logo it has.

Since 1000 grit was taking too long, I switched to 400 grit. This seemed to be a decent middle ground. It wasn't too coarse to tear up the aluminum but just enough to take off the anodization a little quicker. You can see I managed to scratch the camera lens cover a bit... don't worry ;) FYI: anodizing can be removed via a chemical bath, but who would be willing to put their whole phone in a vat of liquid....

Now that I was down to bare metal I switched to 3000 grit sandpaper I picked up from O'Reilly's Auto Parts. This smoothed out a lot of the larger scratches from the 400 grit paper and gave a good dull, almost brushed, look to the aluminum.

Now that I had a mostly blemish free surface, I used Turtle Wax Polishing Compound to smooth out any remaining small imperfections. The final step was to use Mothers Aluminum Polish to get a nice mirror finish.

I was pretty satisfied with the result, however, I had to do more...

I recently stumbled across this article on Hack A Day which gave me the inspiration to do the same.

For everyone's information, after polishing the back, this is what your phone will look like after 2 weeks of typical use (for me at least).

Before I started the etching process I had to give the back cover a good re-polishing. Once that was complete I decided on the design I wanted. Typically in most DIY etching, people use some kind of paint or resist to block the areas they don't want etched. Luckily I have an awesome brother-in-law who recently got a hold of an old plotter. So I whipped up a design in Illustrator and he took care of getting me a vinyl cutout to use. Of course I had to go with the two sites I frequent the most as my design... (yes, I know it's a little off center. I got in a hurry ha-ha)

Instead of going with a vinegar and salt solution for my etchant. I decided on a mix of Copper Sulfate, Sodium Bisulfate and table salt. I used a 45% Copper Sulfate, 45% salt, and 10% Sodium Bisulfate mix.

The Copper Sulfate comes as a chunky blue rock/crystal. So I hit it with the mortar and pestle to make dissolve better in water.

After mixing everything in hot water it was time to etch. I used an old 12 volt 1000ma wall wart I had sitting around for my power source. I wired the phone by wrapping it with 1 foot of bare copper wire and tightly wrapping the wire with electrical tape to make sure it would contact the aluminum. I wrapped another wire around a cotton swab tip and connected it to the negative terminal of the wall wart. After making sure the phone was powered off. I connected the positive terminal of the wall wart to the bare wire attached to the phone, making sure it was in contact with the aluminum by testing it with a voltmeter.

Once satisfied with the etch, I cleaned the surface off with a damp paper towel. All that was left was another polish with the Turtle Wax and the Mothers Aluminum Polish. Here is the final result.

A couple of notes:

1. The phone "seems" to get warmer than what it did before (only while watching videos or playing a graphics heavy game). I haven't checked/compared the actual stats, it's just what I have noticed while holding phone.

2. The white plastic that separates the top and bottom will get a little grey from the sanding and polishing. Goof off seems to be a great remedy to make them white again.

3. The scratches on the camera lens protective cover were buffed/polished away while using the Turtle Wax Polishing Compound. Also, the scratches were never over the center portion and did not impact the picture quality while they were there anyway.

4. The speaker phone mic will get compound/polish in it, however a light tap on a table, with the mic facing down, while the compound is still wet removes most of it. Any residual stuff left in the small hole can be removed (CAREFULLY) with the tip of an exacto blade.

5. I have not had any issues with my signal, nor any issues with the mic on the phone since doing this.

I shouldn't have to say this, but anyone who tries this, be careful. You can seriously mess up the phone and I am not responsible if you follow my examples and something goes wrong. Do this at your own risk.

If you would like to do this and have questions or need help, let me know.

-Crack