Tonight I spent some time sanding smooth certain portions on the inner dome.
The first section I worked on was the area around the rear PSI. Recall that no panel from the outer dome conceals this space, so it's important to sand it smooth before painting. I started with 60 grit sand paper to work out the deepest spin lines, and worked my way up to 220 grit.
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Once that was done, I wrapped some 100 grit sand paper around an old bottle and worked on sanding the hole for the rear PSI to be as circular as possible. I also did a fair amount of sanding by hand for fine adjustments.
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I periodically overlaid the throwaway panel over the hole to make sure I was sanding to the right size and curvature.
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The last item of business was to sand the area on the inner dome underneath the "picture frame" panel. This area also shows through to the outside world.
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Starting with 100 grit sand paper and working up to 400 grit, I sanded this reasonably smooth.
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I propped the panel that will eventually go on the dome in place, so I could ensure that enough area had been sanded. I may do a little more fine sanding, but for now this will do.
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Incidentally, here are was these two areas look like on droid #1.