Some high-end Thinkpad had MgCast (magnesium alloy, really aluminum with magnesium) lids. And it was better than plastic. I haven't seen better material for that purpose (Thinkpad down base could be carbon fiber). On other side it can be a good solution to cover aluminum edges with rubber (easier to fabricate than plastic, or even standard rubber with custom cut). --- Double Post Merged, Apr 17, 2019 at 7:41 PM, Original Post Date: Apr 17, 2019 at 7:34 PM --- There are high-end aluminum smartphones by millions and millions, and their wireless coms work without magic A solution is simply: you left a very thin window for radio signals and cover it with rubber. Lots of aluminum phones had this solution. Other solution is to add rubber pieces on aluminum edges, in this way you get shock protection and a way for radio signals, even better grip and even they can work as surface contact when using in a table.