We know that Dynabolts and other mechanical anchors exist for fixing into concrete without the need for any adhesive. And they hold pretty significant loads.

But what about more light duty applications where fasteners need to be less obtrusive? For example, when fixing window frames into concrete, brick or masonry substrates, you need decent holding power and the ability to have moving parts such as sliding window panes move freely over the fastener.

This is where concrete screws come into play. Add the torx head (i.e. a ‘masonry torx screw’) concrete screw, and you have the perfect solution.

With a masonry torx screw, you can easily and quickly fix aluminium extrusions, aluminium windows, timber battens, metal brackets, hinges and light duty metal plating to masonry. A secure hold is enabled by coarse “hi-lo” cutting threads—a combination of a 6mm shaft diameter and a 7.5mm thread width—that can withstand the force of embedment without any damage.

If you use a more generic type of fastener for these applications, you may find that it will securely fix itself into the substrate, but not grip well to the material being fixed. But with the undercut head featuring ribbing underneath, the head itself grips very firmly with the material’s pre-drilled countersunk hole.

But what about that strange-looking head? This is the ‘torx’ part. A six-sided star-shaped driver bit fits perfectly into this part of the head and will withstand greater rotational force than a chisel or philips head before any camming or stripping occurs. Being less common, this type of head is also good for security purposes – reducing the risk of tampering due to the reduced availability of the correct driver bit for the would-be thief.

Mechanical anchors need room in the substrate to expand and grip without cracking the masonry. Masonry torx screws—due to the narrow shaft width and coarse thread—allow for fixing close to the edge of a window frame or any other narrow strip of masonry.

These screws are also available in galvanised class 3 finish.

For more on available concrete screw anchors click here or For All Things Fixings contact us anytime.