When you are making holes in aluminium its important to use a drill-stand and new fresh drill-bits. I used drill-bits from Black & Decker and Bosch. Black & Deckers Piranha drill-bits worked really well.
Aluminium – Use lubricant/cooler
Aluminium have a tendency to get sticky when it gets warm, so its important to use some kind of lubricant/cooler. Methylated Spirit works really well as lubricant/cooler, you can also use a special kind of wax from your local hardware store.
Aluminium – Use high speed and low pressure
The technique you use when drilling in soft metals such as aluminium is different compared to hard metal drilling. Aluminium builds up “swarf” (showed in the picture) that sticks to the drill-bit’s. When drilling in aluminium you should use a fast rotation speed and low pressure, this in combination with the lubricant/cooler will reduce the “sticky” problem.
Aluminium – Avoid using iron or steel screws
Aluminium is highly resistant to corrosion and has the greatest ratio of strength to weight of any of the different metals. However mixing aluminium with other metals like iron or steel will make the aluminium to corrode. I have used stainless steel screws, screw nuts and washers, since stainless steel is compatible with aluminium.
Recommended aluminium drill speed chart
5 mm drill – 3180
10 mm drill – 1590
15 mm drill – 1060
15 mm drill – 790