Tapping Aluminium extrusion

[Web Goblin]

Hi all,
I thought i would make a start on my router build but have hit a problem already.
Tapping the aluminium extrusion wasnt as easy as I thought it would be. Normal straight flute taps are no good for this because the hole is not completely surrounded by material. As you can see it doesnt work vey well.
Looks like I will need to wait till I get back to work on Wednesday to get some spiral flute taps.


Ian