Flush Fit Aerocatch Application to Composite Panels

Flush fit Aerocatch application to composite panels.

Standard flat panels.

Position the catch to suit the application intended. Proceed to cut the panel to allow the flush catch to protrude through as required and as intended to be seen from above. fig 1.

Note: Should it be necessary for the catch to be situated near the edge of the panel, care must be taken to allow sufficient space for the bonding plate on the reverse side.

Manufacture a bonding plate from suitable material, preferably the same material the panel is made from to minimise dissimilar material expansion or corrosion. Approximate bonding plate size would be around 15mm larger than the overall flange of the Aerocatch. A general rule for the sizing of the bonding plate would be twice the surface area of the original catch flange and maybe 4 times the size if the catch will be subjected to high loading.

Fig 2.

Proceed to bond the catch in place. Suggested methods detailed below.

Housing bonded into a flat composite panel

Fig 3.

Cored panels

Depending on the thickness of the cored panel to which a catch is to be fitted, there are two methods of doing so. A. Simple core removal. B. Locally quilting the panel.

A. Cut the catch penetration hole in the panel. You will then need to remove the inner skin of the panel to allow the catch housing to fit flush with the outer skin. Proceed to bond the catch in place similar to the flat panel bond.

This method suits thin core panels. Thicker cores will encourage the adhesive to track into the mechanism of the catch housing during bonding. Measures to minimise this will need to be devised should you wish to install your flush catch in this way.

Fig 4.

B. You will need to mark up an area bigger that the catch to allow ample room to quilt the panel to a single skin. Cut through to the outer skin and dress the core and inner skin in preparation for bonding. Locally bond from the inner skin through to the outer skin as shown in fig 4. Once cured follow the procedure to fit the catch as if fitting to a flat non-cored panel. See fig 1.

Note: Method B can cause some panel distortion visible form the panel surface. This is due to shrinkage from the secondary bonding. Epoxy resins have a lower shrinkage factor that that of Polyester resins. Adhesives and bonding catches in position.

Modern adhesives can present themselves in many forms, from an adhesive sealant to a car body filler. Your installation can be tailored to suit the application and materials you have available to hand minimising the need to purchase expensive adhesives of which you might only need a small quantity. Trade names such as Dunlop and Sika have vast product lines to accommodate most adhesive sealant requirements. Depending on the installation and budget, you local DIY outlet could provide the required adhesive.

Note: Silicone sealants are suitable in some situations but not recommended should you wish to paint the catch and or panel it is mounted in.

Adhesive sealants are favoured if there is excessive vibration apparent in the final application. Car body filler and resin based filler (Pug or Bog mixes) can be a useful way to secure the catch housing in situ. Mostly utilising resin and fillers you may already have. Should you require to make a filler mix using a resin that you may have left over, there are many thixrotrophic additives available form various outlets to enable you achieve this. Some common examples are Finley chopped/milled CSM glass of even French chalk dust. Using these products to fit your catches can build up a large quantity of adhesive and care must be taken to avoid residual heat build up and exothermic reaction during the adhesive’s curing process. Some adhesives will emit a vapour should it reach a high temperature during cure and this can reduce the final tensile qualities of you chosen adhesive.