The Advantages of the Modern Coachbuilder (continued...)


Building a Body

Introduction
Materials & Methods
Metals Used
Restoring a Body
Building a Body
Windscreens
Hood Frame
Panelwork
The Advantages...

'Replacement' or 'replica' - really from a coachbuilder's point of view it doesn't matter, what is important is to establish exactly what is to be done. Usually a customer will come to the coachbuilder with some pictures of his idea of what he wants; lengthy consultations and lots of coffee is always a good idea at this stage so that both have the same visual image of the project from the outset. Examine the pictures, look through all the books you can get your hands on, visit other owners with similar cars, etc., etc. This is not time wasted.

The first actual stage in building a body would be a full-sized drawing. This is absolutely invaluable. If you don't have an actual car to copy, then a good side-on photo or picture is quite important. If you have a chassis with a non-original body, then you must use whatever pictures you have of the original body. But here a moment's caution is in order, for side view pictures taken from a slight angle fore or aft can be deceptive, even though you are trying to anticipate the foreshortening.

Start the drawing with all the known factors you have - the most important at this stage are chassis height and wheelbase - so draw these in full size. Next, add any other explicit information you have - Rolls Royce owners are blessed with a radiator perfect for this - even if a new radiator height is to be set. Then add bulkhead, steering column, gear shift etc., etc., followed by the bonnet line.

Full Scale Drawing for Bugatti Type 50

Now it's time to draw the body you're going to build. If you have a decent side-on picture, strike two vertical lines through the wheel hubs, then divide the picture into a grid of equal squares using these two lines vertically as a start, then horizontally. Do exactly the same onto the full sized drawing, with the same corresponding amount of squares using the same two vertical lines through the wheel hubs on the full-sized drawing as your datum. You should now have two grids, one on the picture of the body you want to build and one full size overlaid onto your chassis details. This is always a useful aid to setting out the outline of the body. After the initial light pencil drawing, stand back from the drawing and begin to adjust the proportions. When you are happy with what you see, ink in with a heavier line. This all might sound a bit 'Heath Robinson' at this stage, but when you think about it, when you're dealing with shape, form and graceful lines, 'If it looks right, it is right'.

The next stage in my procedure is to build a mock-up, full sized onto the chassis. It's at this stage that the creativity of the coachbuilder takes over. Double curvature shape is difficult to draw, so the coachbuilder must not only be a good craftsman but creative as well, because he must be able to interpret shapes and curves and create beautiful lines using things like lightlines, watermarks, bodymaker's sweeps, etc. He is very often vastly underrated, as you only give him credit for his practical skills. Build the mock-up full size onto the chassis. Now it doesn't really matter how you do this or what materials you use - the important point is to convert ideas and image into three dimensions.

This process is invaluable for showing up flaws in design and concept, and apart from agreeing on proportions, you can check personal fit and comfort - some cars look just great but you can't drive them for long, making them great lookers, but bad touring cars. Also, if you can fix and agree on things like seating position in a touring car, then the base of the seat can be incorporated in the structure of the frame, giving extra rigidity across the body, etc.

Mahogany tool box on the running board

Very useful at this stage of the process also is the opportunity to finalise and prove the location and design of fittings and accessories, things like folding screens, hood design, spare wheel mounts, etc. I can't tell you how many times a customer has said to me, 'A really attractive mahogany tool box mounted on the running board, to act as a step-up' always sounds such a lovely feature. But the first time it rains, with the folding top up, step on the box to get in the back!! And only then do you realise with the folding top now at waist height, you'll have to do your best 'Quasimodo' impersonation to get in the back. Thus, the point is made, that with a mock-up you can save valuable time, prove the concept, and avoid quite a few more blind alleys at the build stage.

More usefully, on the major structural timbers or important feature lines running through the body, a mock-up will help to anticipate one of the main areas of compromise from the coachbuilder's point of view, that of solid continuous timber and not risk areas of cross-grain , or a two or even three part timber with lap joints. Cross-grain in the timber will snap like a carrot, but I would always prefer to use as few joints as possible - so here is the compromise, and a mock-up will help to plan the timber runs, joint spacings and frame layout.

If you have the room, build the wood frame on the chassis with your mock-up (or 'maquette' as it is called by the French coachbuilders) next to you. From here on in, it's lots of very skilled woodwork and solving problems as you go, and there will be many - lock positions, door glass runs, sedanca mechanism, three position hoods, etc., etc. - but eventually you will end up with your wood frame.

Introduction
Materials & Methods
Metals Used
Restoring a Body
Building a Body
Windscreens
Hood Frame
Panelwork
The Advantages...

[ Download a Microsoft Word File to Print Article in Full ] TOPNEXT
    [Menu]