Drilling holes in aluminium

So I had a go at drilling holes in my aluminium section. They needed to be 5mm for the pillow blocks I bought. I've got a dremel drill press. It handles bits up to 2mm and vibrates so spectacularly anyway that I gave up on it immediately. That left me with my trusty cordless drill. I used an automatic punch to get started, but couldn't get the bit to stay put, even with a 2mm pilot.

This is going to be a bit of a problem: positioning the bearings in-line is rather important.

I'd love to buy a mini drill press or milling machine, but it's a little hard to justify, because I have limited storage space, let a lone a bench to attach it to, which would make it unlikely I'd get it out and use it much.

London Hackspace have a small milling machine. Perhaps I should join. They look a lot better organised in their new premises.

Anyway, on my travels I found IXI-Devices. They might solve my problem in several ways: They have pre drilled aluminium angles and stips. They sell very tiny milling machines.

Finally, they have turntable bearing rings. These give me a completely different way to solve the problem: I just attach the two hemispheres to the turntable bearing, and instantly, they are rigidly connected. Or maybe you can only push down on the turntable, and not pull. And they are steel so I guess they may be heavy. I guess I'll have to get one to find out. It's the cheapest potential solution so far, anyway.

On the off chance anyone stumbles on this, feel free to leave comments regarding the efficacy of Bohler/Kaleas mini tools. They are pretty reasonably priced, and look like they are the sort of scale I could use on my desk.

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