Technical Resources - Action Fastenings

The Mini-Undercut+ anchor is an internally threaded, self-undercutting anchor designed for performance in cracked and uncracked concrete. Suitable base materials include post-tension concrete (PT slabs), hollow-core precast concrete, normal-weight concrete, sand-lightweight concrete and concrete over steel deck. The Mini-Undercut+ anchor is installed into a pre-drilled hole with a power tool and a setting tool. The result is an anchor which can provide consistent behavior at shallow embedments as low as 3/4 of an inch. After installation, a steel element is threaded into the anchor body.

Features

Ideal for precast hollow-core plank and post-tensioned concrete slabs
Cracked concrete tested alternative to a mini dropin anchor
Redesigned ANSI carbide stop bit with enlarged shoulder for accurate depth
Anchor design allows for shallow embedment as low as 3/4 of an inch
Internally threaded anchor for easy adjustment and removability of threaded rod or bolt
Drill and drive the anchor with one tool for fast anchor installation

Applications

Tension zones, seismic and wind loading applications
Suspended Conduit
Fire Sprinkler & pipe supports
Cable Trays and Strut
Suspended Lighting

This is another category of fasteners in which this terminology gets used interchangeably on a regular basis. To find the right fastener, understanding the application is the best method. Here are a few points to remember each of these types of fasteners.

Self-Tapping

Self-Tapping screws have the ability to cut their own threads as the screw is driven into the base material. These screws are used in situations where the fastener is driven into a pre-drilled hole. Other common terms: Sheet Metal Screws

Self- Drilling

Self-Drilling Screws ARE self-tapping screw with the added feature of a drill point. The drill-shaped point that cuts through the metal or steel which eliminates the need to drill a pilot hole. The drill points are numbered between #1 thru #5 which vary based on the thickness of steel the point can drill through. Other common terms: Drill Bit Tip Screws, Tek Screws, Iron Eaters

Self-Piercing

Externally threaded fasteners with the ability to self-pierce light gauge metal and tap their own mating threads when driven. Other common terms: Needlepoint screws, Zip Screws

“I need ½” x 2” bolt” is what our customers will ask for. However, this is just the beginning information that we need to match the right fastener with the right application.

Bolts can be confusing, especially when we aren’t talking the same language. Below is a brief explanation of the differences between hex bolts, hex cap screws, and hex tap bolts.

Hex Tap Bolts

Tap Bolts fully threaded regardless of size. The threads on a tap bolt goes from the tip all the way to the underside of the head of the bolt. They have a weaker tensile strength but the extended threads make them more suitable for situations where hex cap screws may not function well. Tap bolts are popular because of the versatility a fully threaded fastener provides. One length of a fully threaded tap bolt can be used to replace several lengths of a standard (partially threaded) hex bolt.

Hex Cap Bolt

Hex cap screws may have a built-in shoulder (un-threaded area under the head) which increases tensile strength of the bolt. However, the threaded length of these screws may be limited and therefore, they are not suitable for all applications. A hex cap screw has tighter tolerances on the body dimensions and features a chamfered end and a washer face under the bolt head. A hex cap screw is often called a finished hex bolt.

Hex Bolts

Hex bolts have a flat end and lack the washer face under the head. They are typically manufactured using a hot-forging process. They typically are not fully threaded but are threaded based on the formula: Two Times the Diameter + 1/4”.