How To Size Sheet Metal Screws

This is how the diameter is represented for screws in the metric system.

How to size sheet metal screws.

8 x 1 2 8 x 3 4 8 x 1 by jetovo 12 99 12. Us sheet metal screw diameters. The oval head types of sheet metal screws resemble the regular flat head screws but have slight variation. The engineered drill point and flute remove material efficiently and properly size the hole for threads.

Consequently burrs are common. Types a and ab are usually considered interchangeable. 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.

The diameter refers to the major diameter or outside edge of the threads. Regardless of the material the driving point needs to be larger than the depth of the material being driven into. These rivets feature more girdles on top which help in providing a more finished appearance. 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.

Screws with a diameter smaller than 1 4 have a nominal size indicated by a number e g. 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. Hex head roofing screws provide secure metal to metal fastening with strong holding power without the need to pre drill.

If you have some stray screws and bolts a k a. 1 4 and larger diameters are shown as inches. 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. Hex head roofing screws teks 9 x 1 1 2 in.

Decimal nearest fractional 4 112. Types a and ab which have a standard point and blunt point type b are common sheet metal screws. Print this page. For example 5 0 means the screws have a diameter of 5 mm.

If the metal is thicker and harder thread cutting screws are used.