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Forming
Many processing operations involve heating.Foamalux and Foamalux Ultra are thermoplastic materials which attain an elastic state and are therefore formable at material temperatures in the range 115-135°C. The panel to be shaped or formed requires even heating throughout its area and thickness. The component formed in the elastic state, when cooled slowly to a rigid state in the forming device, retains the formed shape.
Heat sources can be hot air blowers, hot gas welders, hot air circulating ovens and infra-red panel heaters: all must have controls which enable good regulation of their temperature and that of the Foamalux.
Heating of one side will usually be enough for sheets up to 3mm thick: above this thickness heat should be applied to both sides, reducing heating times and the possibility of surface damage.
Using radiant heat, a heating time of 20 seconds for each 1mm of sheet thickness and using an oven, a heating time of 40 seconds for each 1mm thickness of sheet are reasonable starting points from which to develop.
Some experimentation will always be required to obtain optimum temperatures for forming, these being a function of sheet thickness and the specific forming operation: sheet colour and atmospheric conditions also have some influence.
It is essential to ensure that all panels are free from dust, oil and any other contaminants prior to any forming operation, as these will detract from the quality of the finished product.
As Foamalux and Foamalux Ultra are cellular materials they are not suitable for forming operations which involve excessive stretching in the elastic state. This will cause rupture of the cells and blemishing of the external surface.
Folding
Cold folding is not practical as the materials will stress and crack. Prior to folding, localised strip heating to about 130°C is required. Heat the material for a distance equivalent to three times the sheet thickness on each side of the fold centre line.
When heating is complete and the required shape produced, it must be allowed to cool on the forming equipment before handling or further processing, to avoid warping.
Foamalux and Foamalux Ultra can be folded on a simple jig fitted with a forming tool having a radius of about two and a half times the sheet thickness.
Drape Forming
Where a specific thickness of Foamalux or Foamalux Ultra is to be curved to a smaller diameter than is possible by cold bending, or it is required to form a simple curved skin, it is possible to do this by softening a panel to an elastic state, draping over an appropriately shaped pattern and retaining it until cooled and rigid.
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