First, I will post pictures, design, etc...when I have a little more of it built. But right now I have the following problem:
Explanation of Problem:
I have my T-slots cut, and have the hardware to put it together. I use brackets in some places (a no-brainer) and Anchor-Fastner/Butt-Fastner in others. The Anchor-Fastner/Butt-Fastners are round disks that sit in the T-Slots, but you have to drill a hole somehow for them to sit in the metal extrusions. The hole has to be 13/16 diameter with a flat bottom, about 3/4" deep. T-slots Inc does sell a bit which they call a "13/16 Counterbore Cutter". They don't say wheather it's for a drill or a mill. It costs $62.50 US which just isn't going to happen. I need a cheaper fix.
Question:
So, how can I drill a 13/16" diameter hole, 3/4" deep, with a flat bottom in aluminum with my Ryobi 10" Drill Press?
Things I thought of:
1. I thought about using a regular bit and just not going all the way down, then taking my air-powered die-grinder and boring the hole deeper. Very messy and not very precise.
2. Thought about using a Pilot-Point bit which is flat with a small guide point in the middle. But the guide point would put a 1/4" hole all the way through the metal. I don't like that.
3. I can't afford to take it to a shop.
Any ideas? Some special or weird bit? What am I overlooking?