Coloured Dome Caps
These Domed Cover Caps are made from hard-wearing polyamide for increased durability. They have a two piece construction with ‘click-on’ action for speed of installation. Offers a concealed yet aesthetically pleasing finish where screws would normally be bared to the elements or the eye. Used for many sign and sanitary installations as well as cupboard and carcass assembly.
Coloured 2 Part Cap & Washer Screw Covers
2-part product, comprising:
- a plastic washer (base), through which the screw or other fixing is inserted, and
- a plastic cap (dome), which locks over the washer, providing an air & watertight seal that protects the fastener head from rust and corrosion.
Available in three sizes:
- Size 4/5 suits 4gge to 5gge (Metric 3 – 3.5);
- Size 6/8 suits 6gge to 8gge (Metric 3.5 to 4.2); and
- Size 10/12 suits 10gge to 12gge and ¼” (Metric 4.5 to 6)
2 Part Product
With 96 colours and your choice of Gloss or Matt finishes (all held in stock in the UK). We can match 1000’s of materials, including laminates, composite panels, paints, fabrics, powder coats & vinyls used in the UK – making our 2 part caps a very cost-effective way to not just hide, but also protect your fixings.
The 2 part Cap & washer is available to suit either Countersunk screws, or for any of the ‘Flat-Bottom’ fixings (such as pan-head screws). Using the correct washer type will support your fixing properly, giving improved clamping performance and prevent the screw distorting the washer.
How to use 2 piece Caps
The fixing is secured through the washer into the workpiece. The cap is then “snapped” over the washer, mating by means of an interlocking peripheral groove and flange. This provides an airtight and seal that excludes atmosphere and protects the fastener head from rust and corrosion.
Why is the airtight seal important?
It all has to do with how gases and water vapour behave in enclosed spaces, and is governed by a few Laws of Physics, such as Boyle’s, Charles’, Dalton’s & Henry’s. In essence, once water enters a space (because it is not sealed properly) instead of the water evaporating out again later, it becomes water vapour and remains in the space for a much longer time.
In a climate such as the UK’s, this means the screw-head is continually in water & oxygen environment, never getting to dry out properly. This can cause the fastener to corrode (rust) up to 20 times faster than if a cap had NOT been used! This effect can be easily confirmed, by examining vehicles that use hinge-caps over the number-plate fixings. Even on cars less than 6 months old, zinc-coated screws will show signs of advanced corrosion.
Similar issues arise with ‘polytop’ style plastic-coated screws. Often the plastic coating will crack as the screw is being tightened into place. Water can enter these cracks and cause accelerated corrosion, resulting in visible rust streaks.
Uses & Applications
Because they are UV-stabilised and completely seal the head of the fixing, our 2 part caps are ideal for exterior as well as interior applications.
Even in extreme environments, Caps can be expected to last for 10-15 years, all the while protecting the screw head against corrosion.
These caps are used in the following industries:
- Aluminium frames (shower screens, windows, doors and wardrobes)
- Shop fitters
- Caravans, mobile homes & transportable homes
- Boats (from small runabouts to Navy frigates, high-speed ferries and ocean liners)
- Signs
- Vehicle number plates – specific colours are available to match UK front and rear plates
- Cabinetry (concealing all types of fixings, incl. the screws used with door handles and knobs)
- Furniture upholstery
- White goods
- Electrical and signalling control boxes and panels
- Other vehicle applications – buses, trains etc, Horse floats and other trailers
- Aircraft – private and corporate aircraft up to BA 777’s and Airbuses
- Aftermarket decoration of motorcycles, SUV’s, lorries and HGV cabs