Epic fail drilling into aluminum

[fastpakr]

I have a set of signal lights to add on to the hard cases that live semi permanently on the motorcycle. After gathering the lights, ordering a breakout harness for the factory wiring (to avoid cutting into anything), finding weatherproof screw down connectors to pass everything through, etc, I thought I had a solid plan.

Then came the showstopper I never expected…

The cases are just aluminum, maybe 1/16 thick. And I have failed MISERABLY at drilling into it. Every bit I’ve tried just happily spins right on the surface without biting in at all.

I’ve got a nice center punched dimple to get things started, so the bit isn’t walking at all. Brand new titanium coated bits. Oil to keep the bit from overheating. Pressure against the back of the drill. Steady low rpm. After minutes of consistent drilling, I’m lucky to have a decent mark showing where the bit was turning.

What the heck am I missing? I’ve drilled through thick steel faster than this. So far I’ve managed one hole after hours of experimenting, and that one mostly involved frustration and burning my way though. That leaves another 14 holes to drill and I’ll be lucky to finish before Medicare kicks in.

All I need is a 1/8 hole. Once I have that, a step bit rips through the aluminum to whatever size I need (the one successful hole proved that). It’s not that the aluminum is exceptionally strong or anything. It’s just protected by Elvish incantations that are beyond my skills.

 

[Curious Hound]

Try putting the drill in "forward".


Seriously, it sounds like you're drilling stainless steel.

 

[fastpakr]

Try putting the drill in "forward".


Seriously, it sounds like you're drilling stainless steel.

I have checked the drill direction so. many. times. Everything in me wants that to be it.

I guess it’s possible that they’re really stainless, but they certainly aren’t advertised as steel. Magnet test?

 

[Curious Hound]

Magnet test?

Most stainless steel alloys are non-magnetic. so, that may not tell you much.

 

[Roert42]

Could be chrome plated.

Chrome is very hard, very adverse to abrasion.

Aluminum is very soft, like copper, and drills super fast.

 

[fastpakr]

Could be chrome plated.

Chrome is very hard, very adverse to abrasion.

Aluminum is very soft, like copper, and drills super fast.

Yeah I’ve never experienced anything like this before with aluminum.

 

[alwaysFlOoReD]

Cobalt drill bits work on stainless. If that doesn't work then it's chrome plated. For that use a dremel grind stone to remove the chrome.

 

[85_Ranger4x4]