Finishing & Surface Treatments for the Aerospace Industry

For many of the components we produce, the finish is as important as the machining or fabrication. Edges must be safe to handle, surfaces must be clean and free from contamination, and the appearance must match the environment the part is going into, whether that is an aircraft cabin, an avionics bay or a nuclear plant.

Finishing at GASE is used to:

• Improve appearance and give a consistent cosmetic finish
• Remove burrs and sharp edges and make parts safe to handle
• Prepare surfaces for painting, plating or bonding
• Control cleanliness and foreign object debris before final assembly

Because we are working for aerospace, nuclear and high technology customers, these steps are guided by clear procedures and linked back into our AS9100 quality system.

We run a range of finishing and surface preparation processes on site, including

• Straight graining and thicknessing
• Bead blasting
• Vibratory deburring and rumbling
• Ultrasonic cleaning

These are supported by managed subcontract finishes such as painting, powder coating, plating and anodising to customer specification. The combination allows us to give each part the level of finish it needs, whether that is a simple deburr or a fully prepared, coated and cleaned assembly.

Straight graining and thicknessing are carried out using Time Savers equipment, chosen for its ability to produce a consistent, controlled finish on sheet and plate. This is particularly important on visible panels and covers, where customers expect a uniform appearance across a full set of parts.

We use these machines to

• Apply a controlled grain to stainless steel and aluminium panels
• Remove small surface imperfections and marks from earlier processes
• Improve flatness and thickness consistency over larger areas

This sort of surface preparation is often done prior to painting, anodising or other coatings, but can also be used as the final finish where a clean, brushed metal look is required.

For parts that need a uniform, matte finish, we use Guyson Euroblast bead blasting equipment. Bead blasting helps to remove light scale, minor marks and machining lines, and can be used to blend welded areas into surrounding material.

Typical uses include:

• Providing a consistent finish on machined aluminium and stainless steel components
• Improving the appearance of welded fabrications by blending weld areas
• Preparing surfaces prior to painting or other coatings by lightly keying the surface

Bead blasting is particularly effective where components will be visible in service but must not reflect light or show machining patterns, for example in aircraft interiors or high end equipment enclosures.

Vibratory deburring and rumbling are handled using Walther Trowal equipment. These machines are used to remove sharp edges, burrs and small imperfections from machined, punched and waterjet cut parts.

The main benefits are simple but important. Parts become safer to handle, more comfortable to assemble and less prone to causing damage to wiring, hoses or other nearby components in service. We can tune the process, media and time to suit the material and the level of edge break required, from a light soften on a precision bracket to a more noticeable radius on a handling part.

Vibratory finishing is often used as part of the standard route for fine limit sheet metal components and small machined parts, before they move on to further finishing or assembly.

Cleanliness is critical in many of the sectors we serve. To support this we operate two stage Guyson industrial ultrasonic cleaning systems that are used on parts where contamination, residues and foreign object debris must be tightly controlled.

Ultrasonic cleaning is typically used on

• Components going into hydraulic, fuel and water systems
• Aerospace and nuclear assemblies where FOD control is essential
• Parts that have been through machining, welding or blasting and need final cleaning before assembly or packing

The process removes oils, fine particles and residues from machined surfaces, internal passages and difficult to reach areas, which is difficult to achieve with manual cleaning alone. Cleanliness inspections and FOD checks are built into our quality routines for programmes that require them.

Alongside our own finishing processes, we manage a network of approved subcontractors for specialist coatings and treatments. This allows us to supply parts and assemblies completely finished and ready to use, without the customer having to send them elsewhere.

Typical subcontract finishes include

• Wet paint and powder coating
• Plating, for example zinc, nickel and specialist coatings
• Anodising for aluminium components
• Other treatments specified in customer drawings and procedures

All subcontract work is controlled and documented through the same quality system as our internal processes. Certificates of conformity and treatment data are collected and stored with the job records, so traceability is maintained from raw material through treatment and final inspection.

Finishing is closely linked with our other in house disciplines. Parts come into the finishing area from CNC machining, fine limit sheet metal, waterjet cutting and CAA approved welding, and in many cases go straight on to assembly once finishing and cleaning are complete.

For example, a typical aerospace fabrication might be waterjet cut and formed, machined for tight tolerance features, welded, bead blasted, vibratory deburred and ultrasonically cleaned before being assembled with bought in parts and packed for shipment. Because we manage each stage, we can align the level of finish with the function and location of the part, rather than treating finishing as a generic step at the end.

This joined up approach means less handling, fewer separate suppliers and better control of cosmetic standards, which is particularly important for visible parts and assemblies.

All finishing and surface treatments sit within our AS9100 quality management system. Inspection routines are tailored to the part and its end use, and can include dimensional checks, visual inspection against approved standards and cleanliness or FOD inspections where required.

For parts that go on to further treatments, we can confirm that surface preparation steps have been completed to spec, for example grain direction, Ra levels or edge conditions. Where customers provide their own cosmetic standards or sample panels, we can inspect against those and agree acceptance criteria before production.

Because finishing is part of the same controlled route as machining, sheet metal and welding, any issues can be traced back and resolved promptly, rather than being discovered late in the process or at goods in.

Finishing and surface treatments support almost every product that leaves GASE. Examples include

• Aircraft seat floor skins and internal panels that need a controlled grain and clean appearance
• Aircraft boilers and welded assemblies that require bead blasting, cleaning and cosmetic blending
• Nuclear plant fire traps and safety structures that must be prepared for coating and kept free of contamination
• Electronic and communication enclosures where both appearance and edge safety matter

Sectors served include aerospace, defence, nuclear, marine, space and telecommunications, along with other high technology industries where both technical performance and presentation are important.

By using GASE Engineering for finishing and surface treatments you gain access to in house straight graining, bead blasting, vibratory deburring and ultrasonic cleaning, combined with project managed access to specialist coatings and treatments. All of this sits alongside our machining, sheet metal, waterjet cutting, welding and assembly on a single campus in Crayford.

You have a single point of control for both the manufacture and the finish of your parts, a consistent quality standard from first operation to final inspection and the confidence that components will arrive ready for the next stage, whether that is your own assembly line or direct installation in service.

If you would like to discuss a specific finish, review a current route or see how our finishing facilities operate as part of the wider GASE manufacturing capability, the team will be happy to help.