Cleaning cases

[thebossdj]

Hello!

I started restoring a narrow case Diana 10 years ago and stalled. Mocked most of the bike up in primer, got it running then life, missing parts etc got in the way of finishing it. It will be done by the summer..

Questions are these. After having the motor sit for 10 years after being bead blasted and looking like new they are now looking not as nice plus there is a bit of "flowering" black ugly oxidizing going on the top of the bottom end. Can I re be blast or can using like oven cleaner take the 10 years of age off? Any suggestions?? Tips?

Question 2. I have any un blasted ugly old set of cases I am ready to blast.. what media does everyone use on here for getting them clean. I forgot as it has been years plus I do not have a blast cabinet...

Thanks for sharing your knowledge.

B

[ducridersantafe]

My friend has a vapor blast business, that's what I use. Comes out factory fresh! I have had parts soda blasted before, but I prefer the vapor blasting. Here's a couple of before and after pics on some 250 parts.

[Jordan]

As you have found, standard bead blasting leaves an open-pored, matte finish that is prone to oxidising and also staining.
When new, the crankcases were unpolished as cast, and the covers on both sides were highly polished.
I usually try to clean unpolished Al castings with a hand held wire brush, which leaves a burnished finish, closer to original than bead blasting and not quite so prone to oxidising. Maybe give your cases the wire brush treatment?
It is a sin to use a power tools to restore soft metal, either wire brush or polishing buffer.

Jordan

[ducridersantafe]

My go to method is first a good degreasing with straight simple green, then hit it with 0000 steel wool and Blue Magic metal polishing creme. Keep rubbing until the color and sheen is even, then use a dry, soft cloth (with more polish if needed) to buff it to a nice shine.