Hi again, I've been somewhat occupied with work lately, hence, the radio silence. I've got offers on nearly all main components and the intended design seems to be within budget. One loose end is the aluminium plates which I'll have to have made for me and to that end I wanted to ask a practical question (as I have very limited experience working with metals); what tolerances do you use on screw holes? More specifically, I'll probably end up using a combination of M5, M6 and M12 screws and 20mm aluminium plates.