How To Size Sheet Metal Screws

Screws with a diameter smaller than 1 4 have a nominal size indicated by a number e g.

How to size sheet metal screws.

The engineered drill point and flute remove material efficiently and properly size the hole for threads. Hex head roofing screws provide secure metal to metal fastening with strong holding power without the need to pre drill. Their heads can be either phillips head or slotted head. If the screw size includes a dash with a number following it that is the number of threads per inch tpi.

If the metal is thicker and harder thread cutting screws are used. These rivets feature more girdles on top which help in providing a more finished appearance. This is how the diameter is represented for screws in the metric system. If you re buying screws with the measurements listed on the packaging in the metric system then the first number represents the diameter.

Jetovo 150 pack 410 stainless steel wafer head phillips self drilling screws sheet metal tek screws assortment kit modified truss head self driller size. Us sheet metal screw diameters. These screws are also available in stainless steel and also in zinc plated. 8 x 1 2 8 x 3 4 8 x 1 by jetovo 12 99 12.

Sheet metal screws were originally designed for metal like for use in a b vent pipe but can be used for a number of other applications too they can be used with plastics rubber or plywood. The diameter refers to the major diameter or outside edge of the threads. Teks 9 x 1 1 2 in. Consequently burrs are common.

1 4 and larger diameters are shown as inches. Decimal nearest fractional 4 112. If you have some stray screws and bolts a k a. For example 5 0 means the screws have a diameter of 5 mm.

Regardless of the material the driving point needs to be larger than the depth of the material being driven into. Fasteners lying around and aren t quite sure what size they are or if you need to replace a missing bolt on a piece of machinery and need to know what size to get here are some methods to easily figure that out. Print this page. Sizes typically range from 2 to 3 8.

Hex head roofing screws teks 9 x 1 1 2 in.