You told me 'handheld drill'
I found some die grinders with adjustable speed. But that's not the problem, if I must use tungsten carbide rotary file so I will use one. I just searched the tool I need.
It's not only for the weight but also because I love to have pimp parts on my bike, doing myself some prepared parts, ... I really enjoy doing mechanic on bike (even if I prefer all the same ride my bike).
and as I've already said it, the tool will be not only for rims But also for works others than on the bike