I often drill 1 /16-in.-diameter angled bleeder holes deep within workpiece

cavities. Since standard-length drills don't reach, I use an extension made from drill rod. The trick, however, is securing the drills in the extension.

After inserting a drill into the extension, I soft soldered it in place, but the drill loosened and broke. To remedy this, I applied a few drops of 910 cyanoacrylate adhesive on the drill's shank before inserting it into the extension and gave it a few minutes to dry.

The drill didn't break or get stuck when dull. Instead, it completed the hole and then gradually loosened. I removed the drill with needle-nose pliers, reglued it into the extension, and drilled the next hole. This setup eliminates a lot of broken drills. 


http://www.americanmachinist.com/304/Issue/Article/False/9721/Issue