I read here that aluminium should be cleaned with a metal brush reserved to this usage prior to welding. So I went to my favourite shop to buy a new brush for my grinder. Then I realise that there are
2 sorts of stainless brushes: one where the bristles are individually free and one where the bristles are grouped and twisted together. Normally, I use the second type for steel, it is much stronger. But aluminium is softer than steel, so the brush that works better with steel maybe too hard for aluminium.I feel a bit silly for bothering the group with such a simple question. Maybe half the people here use one and the other half the other?