Working and Finishing
Where numbers of items are required with batch identification, these will be marked up on unseen faces to suit specific needs.
Cutting and shaping
All cut edges will be smooth and free from distortion.
Burrs on aluminium do not usually cause a handling problem but the Company’s high standards of workmanship require excessive burrs to be removed.
Drilling and punching
Hole edges should be clean and without visible distortion.
Flattening and straightening
During working, including welding, it is quite usual for aluminium to bow, curl or distort (e.g. by heat), working in localised areas of larger sized items and / or shearing to marginal size ratios. Corrective action is undertaken to minimise or eradicate these problems without theneed for this to be requested.
Scribing lines are not used on visually important surfaces or critically stressed areas.
Press brake and roller bending
Sheet aluminium to be bent or roller formed is to be protected whenever possible with a removable protective film on the good side to minimise the effects of tooling pressure. Suitable ‘cold forming’ grades of sheet aluminium are used to avoid the necessity for annealing procedures.
Section curving operations should not produce significant distortion on the inside radius or thinning on the outside.
Sheets may be rolled to a wide range of radii consistent with the specified curvature.
Springback is caused by elastic strains. Preliminary test bends will identify any potential variance from the required angle of bend, and due allowance by over bending will compensate for this condition.
Workshop personnel are informed of any surface finishing technique to be carried out, subsequent to production. Items are therefore made to the required standard consistent with the final surface treatment.
Weld finishing for decorative work will result in the weld bead being cleaned (ground flush) with the surface of the material. For added strength, structural welds are normally left in the uncleaned condition.