I can confirm that cleaning the rust and crap off the bottom of a car is not something you want to do. you want to pay someone else to do it. There is no fun, pleasure or joy in doing this. Anyway, I went through this to show you why you don't want to.
First, get a selection of wire wheels that will fit in your hand drill. I started using a battery drill but even using an 18v Panasonic drill, the corded version was so much better and the cord didn't really get in the way when working. The ones on the right were good for most surfaces. The bright copper wheels were best for cleaning narrow pipes as you could get them to clean all around the pipes and tubes. The skinny round on on the left was okay for small spaces.
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WCA!, on Flickr
Here is a 'before' of the hub
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A close up of my finger tip and the cracking rusty surface of the metal.
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Breathing mask and goggles before starting. Believe me, you really, really want to be wearing these or preferably one of those fully enclosed white space suits.
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The wire brush in action. Be careful not to brush the rubber bits as they disappear quicker than the rust.
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I am not sure of the benefits of removing rust from the brake discs but they were easy to get at so I gave them a quick once over.
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A bit less scabby now.
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The crusty flaky surface is now smoother. Still some rust but I plan to paint it all with POR15 which is fine only small amounts of rust as long as you remove the flaky bits.
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Having cleaned up the drivers side hub I decided to start at the front of the car and work my way back underneath it. Lots of pictures, mainly for my own record but basically you are stuck in a cramped space in a cloud of rusty dust with a drill whirring in front of your face. No pleasure at all.
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This got me about half way along the car and I decided to call it a day. I know it is an early finish but I am not being paid so there is no rush.
And this is what my nice woollen carpet looked like after all that cleaning
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WCA!, on Flickr
I shook the carpet out but needed to clear out all the dust. Google suggests compressed air so I opened the garage door and generated some compressed air in my own special way.
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