I am trying to join 2 pieces of Aluminum angles (6061, 90 degree, 1/16" thick) together using this self-driving screw:

  • Extra-Wide Rounded Head Drilling Screws for Metal
  • #8
  • 1/2" length
  • From McMaster Carr (Part # 91515A100)

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Problem: Since the 1/2" long screw is longer than two 1/16" thick Aluminum angles stack together, the sharp end of the screw will be protruding out and may injure someone.

Ideal Method: Quick, cheap and safe. Need to make thousands of connections in a day. Looks does not matter.

Is there a quick way to make the end less blunt?

Or will you suggest replacing the self-drilling screws with self-tapping screws which have a blunt end?

Background: I am using self drilling screws with a 20V cordless drill because it is quicker using than using rivets, and I need to make thousands of connections in a reasonable time frame. The rivet gun seems like it will tire me out real quick. I also have no experience using rivets.

  • "Self-piloting". No screws drive themselves. :) Just grind it off with an abrasive wheel. The alternative is to drill and tap for machine screws of appropriate length.
    – isherwood
    Jan 22, 2018 at 20:03
  • @isherwood Sorry for that! I have a cordless Dremel that can attach an abrasive wheel (Dremel Aluminum Oxide Abrasive Wheel 1" Diameter). Do you this this is suitable, or will it wear out quickly after using on 10-20 screws?
    – Nyxynyx
    Jan 22, 2018 at 20:16
  • Self tapping will still be able to scratch a person. They are not as sharp as the self drilling, but they will scratch. Rivets seem like a good choice because both sides are blunt, and you can get an electric rivet gun.
    – JPhi1618
    Jan 22, 2018 at 20:17
  • You could cut roughly that number of screws with a Dremel wheel. You won't grind them off, but you'll cut them and maybe grind with a stone bit. An angle grinder with an abrasive disk would be better.
    – isherwood
    Jan 22, 2018 at 20:47
  • Take an angle grinder or Dremel and cut off the protrusion
    – Hari
    Jan 22, 2018 at 21:32

1 Answer 1


I would suggest "brute force"; put in nuts and bolts. Although for a similar situation I have used 3 electric drills; One drill puts a pilot hole through both members, the second puts a clearance hole in one member only. the third drives a self tapping screw ( passing through the first member and threading into the second.)

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