Building up to another week off

Since I have some holiday stored up, I'm taking this week off work to make more progress on the Sprite.

In preparation of having the time off, I wanted to get the Mini uprights cleaned up and in primer. I need to get the outer suspension components together so that I can set the wheels correctly in relation to the shell before moving onto making a trial set of wishbones. The easiest way I know of cleaning up old rusty parts is using the power of science.

Since they were free, they used to look a little worse for wear, like this:




But if you put them in a bucket of water mixed with soda crystals and add a battery charger you can use the electricity to reduce the rust on the surface back to iron. This process takes about half a day for each part in my little plastic tub, but that's about all. It's cheap, a piece of piss to do and makes very little mess. It also leaves any machined surfaces perfectly intact and can remove a fair bit of grease too. This was my initial set up, and they were left in overnight:

 

Once taken out, they look better. Not great, but better. Ideally, you should surround each part with anodes (the scrap bits of steel), but I only had two usable bits to hand.

Since they weren't great, I decided to put them back in individually to get them looking better. Once they're given a quick wire brushing to remove any flakes of rust/iron, they look like this:



Not bad for 10-15 minutes work. OK, a blast cleaner would probably do just as well, if not better, but I don't have one of those where as I do have a battery charger and a bucket. This process can be applied to any iron/steel item and the only real limit is the size of the tub and the charger.


IMPORTANT 'Ealth and Safety bit: should you fancy having a go at home, please do. But DO NOT use stainless for the anodes. It makes a rather nasty chemical in the water called [url=http://en.wikipedia.org/wiki/Hexavalent_chromium]hexavalent chromium[/url]. It's mildly carcinogenic and can cause contact dermatitis. Make sure you put the negative wire on the thing to be de-rusted, as getting it wrong makes the part more rusty! Where possible ensure it's done in a ventilated space as the process gives off hydrogen gas in small volumes.


Once they were both clean and dried off, a few coats of engine primer were applied. I'm using that over other stuff as it's supposed to resist temps up to 500F, which should be way above what the uprights see. At some point I'll probably paint them black but they'll only get knocked in the next few weeks, so I don't see the point yet.