Teks Self Drilling Screws Wood to Metal Applications on Roofs

Building on the knowledge gained from manufacturing dual purpose batten fixings, BDN Fasteners have further enhanced the already super-efficient, fool proof POLY-FAST™ Metal and POLY-FAST™ Timber fasteners. We have now come up with a Dual Purpose tek self drilling screw for wood to metal applications, which we named POLY-FAST™ Duo!

Why Choose POLY-FAST™ Duo Teks Self Drilling Screws for Wood to Metal?

POLY-FAST™ Duo is a dual-purpose Teks Self Drilling Screw for Wood to Metal Applications on Roofs. It combines all the fascinating features of its Metal and Timber specific siblings, and is designed for users who are leaning towards a one screw to do it all solution. Why carry two items when you can get things done with only one?

No More Pre-Drilling Expansion Holes

POLY-FAST™ Duo incorporates a thermal expansion hole cutter which creates a sufficiently large, 11mm hole in polycarbonate sheeting to allow for thermal expansion and contraction without the need for reaming a pilot hole, allowing for single tool installation.

Integrated Depth Stop Knurls to Prevent Overdriving

Having additional knurling on the shaft right after the threads is a second feature designed to prevent damage from overdriven screws which deforms the affixed polycarbonate sheets. Knurls on Teks Self Drilling Screws Wood to Metal Applications on Roofs act as a brush to clear off excess swarf created during the drill and drive process.

On Poly-Fast fasteners however, the Depth Stop Knurls acts as a stopper for the thermal expansion hole cutter, which comes to a stop upon coming in contact with the purlins, the depth of which was designed according to polycarbonate ROMA and GRECA profiles; enough so that it provides a perfect seal on the enlarged hole, but not deform the corrugations.

The creme de la creme of the design is the dual purpose Doufix V-Drill, which is capable of drilling through both thick steel and hard timber with ease.

Domed, Weatherseal, Anti-static EPDM Washer

A large Domed Weatherseal EPDM washer with two concentric sealing rims on the washer underside completes the package –

The domed structure provides superior strength against high winds.Two concentric sealing rims holds the 11mm Thermal Expansion Hole Cutter in place prior to drilling and keeps the expansion hole fully sealed after installation.
Two concentric sealing rims hold the 11mm Thermal Expansion Hole Cutter in place prior to drilling and keep the expansion hole fully sealed after installation.