I have an interesting update to this topic. This new idea is not for the faint of heart however! Some of you may see it the same way I do; the yellowed white bricks are ruined anyways, so what the heck.
For quite some time I've been using this polishing kit to remove printing from tiles. It's far quicker than brasso and waaaay less work.
I tried sanding on my heavily yellowed white bricks (this brick was almost the colour of proper LEGO tan!) with one of the mid-grit films and in just a couple of passes, the yellowing started to go away. The materiel removed can be measured in microns so I for one, am fairly comfortable using this process. I'll get some before and after pics up soon but for now I'm going to enjoy my Sunday morning pot of coffee.
Trust me, I think I'm funnier than you do.
Why do I have to add the word "minifig" to my spell checker every time
I use it?!flickrMy blog