Saturday, June 2, 2012

Chrome Dome

Well, the long, long effort to shine the dome is complete. I've been working on and off at sanding the outer dome over the last year. With so much elbow grease involved, it's not something I cared to do all in one shot, but rather whenever I got an itch to. My goal was to get out the spin lines and have a nice dull shine, similar to the medal ceremony scene at the end of Episode 4.



I initially attempted to get the spin lines out by hand, but soon realized that it was probably too big an undertaking without getting carpal tunnel. So I broke down and bought a Black & Decker Mouse Sander at Lowe's. The reviews were mediocre, and had many reports of breaking rather fast. I can vouch that within a few minutes, my first one broke while using the attachment piece. Luckily Lowe's took it back no questions asked and I got a second. I didn't bother with the attachments and it ended up doing a great job. Over the period of a few weeks I used the 80 grit to get out all the spin lines in both the Inner and Outer Dome. Then I used 120 & 220 grits to get the dome to the point you see here:



From that point I resorted to hand sanding using two 3M sponge sanding blocks at 100 and 180 grit. These can be found in the painting department at any Lowe's Walmart, etc. I really liked these since they were able to bend to the shape of the dome and made it a little easier on the hands. I went over the whole dome using vertical motions from top to bottom several times with the 100 grit until I was satisfied that most of the pitting from the mouse sander was gone. Then I used the 180 grit sponge several times as well.



From there I used 400 grit paper dry, and then started a round with it wet. Being single has its advantages in that I just sat the dome hanging over the kitchen sink without anyone complaining. Plus, I was able to watch the living room TV during this phase. I spent an evening each on a grit of paper, wet sanding with 600, 800, 1000 and finally 2000, always using the same vertical motion. At this point the dome felt silky smooth but still had visible sanding lines.



That's where a little tip I picked up watching the webcast of last year's DroidCon came into play. I bought some Bombs Away Metal Polish last year after hearing about it during the Dome presentation. I'd used it a few times on some of the other parts, including the Center Vents. It seemed to do a pretty good job so I decided to go ahead and use it on the Dome as well. After seeing Lasse's results with a drill polishing attachment, I'd had my eye on one from the auto department at Walmart. I finally broke down and got it once I'd finished all the sanding on the dome. You can see the results of using the Bombs Away and polishing ball together.



One pass of the polish still left some unevenness so I worked my way around the dome with two applications to each area. I was very careful on the lower portions where the aluminum is quite thin. I kept the drill as slow as possible in those areas so I wouldn't accidentally break anything if the polishing ball caught the metal. Then I made one final application to the middle, wide section of the dome in order to get out as much of the splotchiness as I could. All-in-all I'm fairly happy with the results. It has a nice shine to it, there's no spin lines at all, and its not quite a mirror finish while still having a few very small imperfections when you look close. Its a good start before I eventually weather it down the road.


1 comment:

  1. This post was a huge help to me! Thanks for posting it.

    ReplyDelete