General Repair Notes; Welding And Gas Process Special Notes - Aston Martin DB7 Workshop Manual

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Body and Trim
Body Repair
Precautions
Paint
Ensure that there is efficient ventilation at all times. Paint spraying should be confined to spray booths.
Anyone with a history asthma should not be engaged in any process which involves the use of isocyanates.
Any operator working inside a spray booth where isocyanates are present must use air-fed breathing equipment.
Supplied air to the visor should be fed at the recommended pressure and filtered to remove oil, water and fumes.
Operators involved in handling, mixing or spraying should wear protective clothing, gloves and goggles to avoid
skin and eye contact. A Paticle mask or canister typr respirator should be worn when sanding.
Applied heat
When welding, flame cutting or brazing and so on, goggles, a mask or fume extractor and flameproof protective
clothing should be used always.
It is especially important when working with polyurethane compounds to use air-fed breathing equipment.
Ensure that at all times the appropriate fire fighting equipment isavailableand that personnel are trained in its use.
Metal repair
Wear appropriate eye and hand protection when sanding, drilling, cutting, chiselling, flatting or welding. Wear a
face mask or air-fed visor when sanding or flatting either body solder or fillers. When a soldering operation has been
completed, remove swarf from the work area and wash your hands thoroughly.
General Repair Notes
The following precautions should be noted before any work is carried out:
• disconnect the vehicle battery ground lead, taking note of the reconnection procedures
• Make sure that you have read and understood the safety related procedures in this section.
Caution: Electric arc welding must not be used on the vehicle as the high voltages produced by this process will cause irreparable
damage to the electrical control and microprocessor systems.
All trim and electrical components in the locality of the repair must be removed or disconnected prior to panel
removal or replacement.
Welding and Gas Process Special Notes
Resistance spot welding, MIG welding and all gas processes may only be carried out on bare, unpainted or unplated
metal. The flanges of panels, which are to be welded together, must be clean, corrosion free and treated as
appropriate with either weld-through or inter-weld sealer.
The resistance spot welding equ ipment used in vehicle repair does not always produce a weld of equ ivalent strength
to that produced in manufacturing. This means that a single row of spot welds should be spaced on a pitch of 19-
25 mm, which will usually result in more spot welds than found in the original factory joint.
Use a resistance spot weld cutter to remove resistance spot welds. Where a new joint is to be MIC welded, cut the
old resistance spot welds from the panel that is to be retained; the resulting holes are then used for plug welding.
Suitable holes may be drilled or punched as follows:
• 8.0 mm for sections up to 1.5 mm thickness
• 10.0 mm for thicker sections.
Always refer to the welding equipment manufacturers diagrams and tables for the relevant procedure.
May 1996 7-3