Drilling cast aluminum:

[A3DSAIL]

I am modding my Gigabyte 3D Aurora 570 case by drilling three 1 1/2" holes across the lower half of the front door. This is made of 3/16" (approx.) cast aluminum. I plan to use a 1 1/2" bimetal hole saw to do this. I have never cut alum this thick before and I would like advice about whether to use some kind of cutting lube because of the thickness and some idea of what drill speed I should use.

I don't have a drill press. I will be using a 1/2" B&D variable speed drill for the job. Any tips I can get would be greatly appreciated. Thanks.

[Beta-brain]

Hi, You need to go quite slowly when using hole saws as they get pretty hot, as a general rule the bigger the drill the slower you go, you can get various cutting lubricants but if nothing else is available clean engine oil or a drop of 3in1 oil is better than nothing.

Make sure the work your drilling is very securely fixed down to stop it moving and turning, use clamps, nuts and bolts or a vice with some wood in the jaws to protect the door anything as long as it won't start moving and spinning around when drilling...not good!

Have a look on this site and there's more info about drill speeds etc, (http://www.ultimatehandyman.co.uk/DIY_Metalworking/drilling_metal_technique.htm) just don't try and rush the drilling by leaning on the drill too hard, it will take a while,hope it helps.

[A3DSAIL]

Thanks Beta-brain, for the tips and the link! ;-]

Anyone else?

[Eclecticos]

Looks like Beta-Brain hit the nail on the head.

Only thing I can think to add is. .
Taking exact measurements, marking out the circle with a compass, drilling a pilot hole,
and remaining directly behind the drill while cutting out the circle.

[A3DSAIL]

Only thing I can think to add is. .
Taking exact measurements, marking out the circle with a compass, drilling a pilot hole,
and remaining directly behind the drill while cutting out the circle.

Thanks, Eclecticos, I'll keep those tips in mind. :up:

[Aud1073cH]

if you can find some heavy duty rubber blocks or pads, they can help save the rest of the finish from the clamps. if the stage of your drill press has slots wider than your piece, you can put bolts along the edges (not through) the piece, so it can't spin.

I agree -
some cutting oil would help with the heat. Just go slow and steady with a bimetal saw.

:)

[b4i7]

its kinda touchy doing it with your type of setup, you only really need to use something like wd40 or some household oil, as far as cutting...you dont want it to be too slow... because then you will just be scraping and not cutting through, scraping will wear down your hole saw