Posts Tagged ‘self tapping screw’

Fastener Facts and FAQs

Keeping up with technology is a challenge. Each new gadget has a different feature than its predecessor, but who really knows the difference between the two? If you want to know the difference between the iPhone4 and the iPhone5, you ask someone who works for the company. If you want to know the pros and cons of HDTV versus 3D, you ask somebody in the television industry. If you want to know about construction fasteners, ask us. Below are some questions we are asked more often than others.

What type of screw gun should be used to install self drilling screws?

For optimal performance, the screw gun should meet the following characteristics:

  • 1800 to 2500 RPM variable speed
  • 6 to 8 amp motor
  • adjustable torque sensitive clutch mechanism
  • depth adjusting nosepiece

What is the difference between a self drilling screw and a self tapping screw?

Just because the names sound similar doesn’t mean they are one in the same. A self drilling screw is designed with a drill bit point. That special point helps to drill into metal without requiring holes to be pre-drilled. Primarily used for metal only, self drilling screws are also known as “tek” screws.

A self tapping screw, on the other hand, has a sharp point with threads and is usually designated as either type “A” or “AB”. (The difference between the two types is the thread size and pitch.) A self tapping screw carves its own thread as it’s being installed, similar to a tap. The difference lies in the fact that a self tapping screw, unlike a tap, requires a pre-drilled hole.

What is the difference between 304 and 316 Stainless Steel?

Not only does the shape of the screw, the style of the tip or the pitch of the threads matter, so does the material that makes up the screw. 304 Stainless Steel contains 18% chromium and 8% nickel. Molybdenum (“Moly”) is added in the 316 Stainless Steel so the percentages differ slightly, with 316 containing 16% chromium, 10% nickel and 2% molybdenum. The purpose of adding the moly is to help the fasteners last longer by resisting corrosion to chlorides like salt water or de-icing materials.

What is a flat undercut screw head?

There are circumstances in which you need more thread and less head in a small amount of space. Flat undercut screw heads are supplied to allow more room on the body of the screw for usable thread. The head height of undercut screws is approximately two-thirds the height of standard flat head screws. Drive depths are reduced proportionately.

Is there a security nut available that cannot be removed?

Security fasteners protect property from theft and misuse. Security screws are constructed with specialty heads that prevent any unauthorized person (anyone without the proper, hard-to-obtain tool) from removing them. And, yes, there are security nuts, too. After tightening to the proper torque, the hex section of a break-away nut shears off leaving a conical nut that cannot be removed.