Advice Needed, Drilling A Hole On The Edge Of A Piece.

I one time ran into a problem similar to yours. The problem is that with the small diameter drill bit and a small runout on your drill press that bit will bend. Make jig with two holes, one that fits over that pin or what ever that is. The other hole for the bit to run through. And you may have to clamp it. If you got a xy table, use it , better yet a mill or mini mill. I can't guarantee that this will work, but maybe it is worth a try. Good luck. Mark
 
Carbide drills are much stiffer than HSS. Carbide PCB drills have 1/8" shanks and typically about 3/8" flute length. You didn't say if you were using a drill press or a mill. I would use a mill because of increased rigidity and control of the feed and positioning. When I drill something like this, I bring the drill down until the tip just touches the work and let it dwell to find its center. The drill will eventually run true. Then advance a few thousandths and repeat. Eventually, you will be deep enough the the drill won't walk and you can continue drilling. When drilling aluminum, use a lubricant like WD40 or AlumTap to prevent galling and possibly breaking the drill. PCB drills are readily available on-line.
 
I drilled the 17 pcs in the fixture, one hole wandered out of the piece.

I'm using my PM25, Its a Mill. A fixture utilizing the center boss, (.125) with the .038 hole .100 from the center would leave .020 between the guide hole in the center and the pilot hole for the .038 drill. Good Idea, but just too small.

The material is .250, unturned, can't drill first. Remember, this piece is .250 in diameter, the boss is .075 long and the whole piece is .270 long. It's a tiny thing.

I have to reorganize how I set it up, the fixture isn't as square as it ought to be, I had to move Y as I moved down the 5 inch length.

Thanks for all the help. Next load will work better, I've also ordered some new drills, hope they have a better point than the one I have. Under a loupe it looks like the end of a baseball bat.

Bye the way, there's another hole at .042 X, .080 Y. I was able to coax the drill into those holes by letting it spin on the surface until it started. I pecked the holes, .005 to .010 at a time.
 
Guys correct me please,but don't a drill bit with a 135* split point tip help keep it from wondering vs 118*?I think that is what I read someplace here----kroll
 
I've hand sharpened bits as small as .100, but .038, I can't even see the end without a loupe. Don't know about 135º as opposed to 118º. For the degree (º) sign, hold down Alt and type 0186 then release the Alt key.
 
Dang Tom LOL did not think about the size,I'm embarrassed.I wouldn't be able to tell with or without my glasses 118 or 135
 
I can't get it to work on my dell laptop--
 
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