Posted on

Precision masking metal fabrication

Why is masking such an important part of precision metal fabrication?

Successful metal finishing can often be dependent on precision masking,  As the finishes applied to metal can often be hard wearing in nature, it’s important that the right masking products are used to gain the desired finish to your metal parts.

Metal corrodes, particularly steel and aluminium which most metal products are made from. The primary reason you coat or “finish” metalwork is to prevent corrosion. The secondary reason is normally visual.

The reasons you would want to mask may vary. From simple applications to complex components with varied masking needs you need different tools and components to provide the best finish.

 Why use precision masking products?

  • Quality of finish
  • Safety
  • Electrical insulation
  • Thread protection

Masking threads:

Masking threaded holes, studs and bolts.

Threads can be male or female on metalwork. There are tons of different weld on and self-clinching fasteners available for designers to choose from. The coating is not always considered at the time of design. Finishes that leave a thicker coat can cause threads to become clogged. The nature of powder coating particularly makes this hard work if you don’t mask first.

Use silicone rubber caps and plugs that are available in huge varieties of shapes and styles to suit your preference and need. Put them in just before you apply powder, bake them and take them out while they’re still warm.

Shop for powder coating caps & plugs

Masking areas around threaded holes and studs

The areas around studs and holes often need to be masked to allow for usually electrical contact points or mechanical pivot points. If there’s a moving part or electrical contact is necessary, a clean metal surface is desirable.

There are tons of different shapes and sizes of standard plugs and caps available to suit most needs, particularly on the smaller side of M10 threads you find the most choice.

Silicone rubber flanged caps and ringed plugs are the quickest and most cost effective components for precision masking holes around threaded studs and holes.

Shop for flanged caps and ringed plugs


Masking flat surfaces

Simple flat surfaces

There are a number of  tapes able to withstand baking temperatures associated with more hard wearing finishes such as powdercoating. High temperature tape is applied before applying powder, baked in the oven and then removed before the components cool. You can purchase all sorts of different widths of tape on rolls. Green polyester masking tape is excellent for flat surfaces but applications requiring more flexibility in the tape benefit from thinner “conformal” tape found from quality masking suppliers.

Shop for High Temperature masking  tapes

More complex flat shapes

High temperature masking tapes can also be die cut to order to suit more complex items needing flat surfaces masking. This is common on enclosures and where gaskets and seals are part of the finished design.

You’re best going to a quality supplier that deals with custom cut shapes regularly to get the best service and advice. When getting shapes cut, you want “right first time”.

Shop for custom die cut high temperature self adhesive shapes


Bespoke silicone rubber mouldings

Even with the thousands of variations of masking solutions already available, the right shape for may well be custom. To make things easiest for a custom moulding you need a CAD/CAM file of the component in question. If that’s not available, it’s a good idea to take some pictures or a video. Your supplier should be used to handling custom mouldings and will offer you a prototype before going to full production.


AFAC offer the widest range of masking products in the UK, many of which are normally available for immediate dispatch from our UK warehouse.  We are specialists in the supply and manufacture of precision masking products for the metal finishing industries.

Call us today on 0845 094 0993 to find out more about precision masking metal fabrication or click here to find out more.