[dustman]

For the experts what?s the best technique for drilling holes in alum that doesn?t destroy the material? Specifically I need to drill the boltholes for the center section bulkhead. I know a couple of wrong ways now. Is there a particular type of drill bit that works best or is a punch a better approach? Type aircraft RV3 Thanks for any help

 

[Mel]

Not quite sure what you're asking here. If you are asking for normal drilling techniques;
For soft materials like aluminum, use high speed (air drill), low pressure.
For harder materials like steel, use low speed (electric drill), and high pressure with plenty of lubrication.
And it goes without saying, always use sharp drills.
A punch is fine if you have the correct size.