Tuesday, September 7, 2010


There are essentially two ways to tackle bodywork restoration. You can carry out the work on a piecemeal basis — in effect, treating the restoration as a series of separate bodywork repairs — or you can begin by stripping the car down to its last nut and bolt and rebuilding the entire body and chassis.
Before embarking on bodywork repair or restoration, it is necessary to properly establish the full extent of rusted or rotted metal on the car. If you omit this then you could discover part-way through the job that some of your freshly welded repair panels have to come off again in order to allow you access to a newly evident area of rot.
The easiest way to discover all of the rot in a car is to strip it to a bare chassis/bodyshell and send it or take it away for dipping in an acid bath. This process strips all paint, underseal and rotten metal from the shell, leaving some surfaces which can be immediately primed and others clean enough to begin welding to. The problems with acid dipping are that the process can thin some panels slightly and might make some otherwise salvageable panels unusable, and that the shell will be left unprotected against rust until you can get some paint onto it.
Begin by probing every panel of the car vigorously with a sharp metal implement (an old screwdriver is useful and a pointed panel beater's hammer is ideal) to find all rust and rot. What you discover in this way will have a great bearing on how work on the car can subsequently proceed, so build up a list of panels which need attention. Your list of all of the bodywork which needs attention might persuade you that it would he better to entrust the job to a professional, or even to consider re-shelling the car or replacing the chassis/floor assembly. Better to have to make that decision now, rather than part-way through a body restoration!
Underseal presents problems to the restorer. No matter how unblemished the surface of underseal, it can hide serious and spreading rot. It has to conic off, and this can be accomplished in a variety of ways.
Underseal clogs abrasive papers and cloths veryquickly. rendering them useless. Ordinary wire brushes
will have no effect on underseal, and high-speed cup brushes used in angle grinders merely rip away filaments of underseal which stick to whatever they hit. Large flat areas of underseal can be dealt with initially using a blowtorch to soften the material and a wallpaper scraper to remove the hulk of it. Have a fire extinguisher handy before trying this! Alternatively, underseal can be scraped away using an old wood chisel. Both of these methods will remove much of the underseal, but leave enough of it on the surface to still clog abrasive papers. Use paraffin to soften the remaining traces of undersea', then wipe it clean with a rag. Again, beware the fire hazard; have a fire extinguisher handy, and do not smoke or work near any naked flame.
It is not necessary to strip back all of the paint work at this early stage; if you do so then the exposed steel will soon develop surface rusting. Do use a magnet to reveal any patches of filler or GRP, and probe the usual trouble spots (see Chapter Two) vigorously with a sharp metal object to check for rot.
When you examine the car to determine what work needs to be carried out, bear in mind that rotten heater channels almost invariably point to rotten floor edges. It is common practice to replace heater channels but not
floor edges, because to replace the latter the bodyshell must be lifted away from the chassis. This is not good practice, because sooner or later (usually sooner) the floor edges will rot to the point at which the job has to be carried out in full and the bodyshell and chassis parted. Replacing a heater channel without lifting the bodyshell off the chassis is also bad practice because the final welding up of the heater channels (particularly the ends) does the belly pan gasket no good at all!
The actual method of working and order of work will depend on the extent of the work. A single task such as replacing the rear bodyshell/damper arm mount may be carried nut with the body on the chassis, but for a thorough restoration (which will usually entail floorpan replacement) it is as well to strip the car down to the point of separating the body from the chassis assembly. The following text describes a complete body-off restoration, with each task approached so that it describes how the individual job can be carried out in isolation where applicable.

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