Having designed a plasterboard fixing capable of withstanding high load factors, we thought the next logical step would be to design a picture hook to work in perfect harmony.
These hooks (roundels) are particularly effective when used as horizontally opposed pairs for hanging large, heavy items such as mirrors. Conventional hooks are not designed to work in pairs as they are not optimised to work with the lateral forces that are generated when more than one fixing is deployed – they skew from their vertical position, which can be problematic. Our hook can connect directly to the plasterboard as there is no protruding front flange from the fixing itself. This is highly advantageous due to the extended surface area in contact with the plasterboard, which produces a strengthening “sandwiching” effect on the plasterboard and also gives us the opportunity to utilise a locating ring to assist with installation. Orientation issues are permanently removed. Unlike conventional hooks, the central fixing bolt resides underneath the picture wire, which acts as a further failsafe.
The Hook from Grapplefix has some distinct advantages over conventional (hook-shaped) hooks, summarised below:
The hook works equally well for smaller, lighter loads, but when hanging significant loads (above 10 Kg), we recommend using a 7 x 7 (49 individual strands) 1.5 mm stainless steel wire, preferably PVC coated to reduce fraying (total diameter 2 mm).
The breaking strain of this type of wire is usually around 140 Kg (check the specification prior to installation). It is made up of 7 bundles, each containing 7 strands. This configuration gives the wire the required flexibility.
Other wire configurations such as 7 x 19 are even more flexible (therefore allowing for increased diameters) and a 2 mm, 7 x 19 uncoated stainless steel wire would give a breaking strain up to 230 Kg where extra safety multiples are required. Again, check the specification carefully prior to installation.
It should be noted that the picture hook slot is limited to wires (including any additional coating) of 2.5 mm (maximum) diameter.
Optimally, the ends of the wire should be as close to vertical as possible (with the two hooks positioned horizontally apart as far as possible), as this represents the configuration with the lowest resulting tension in the wire. However, this may not always be practical and is an optional configuration. The ends of the wire may diverge (as shown below – the less the better), be almost vertical (preferred) or even converge if required.