I did say that I would describe as best I can how I've being going about making the panels.
As mentioned, I'll leave the panels pictured above for now, even though they all need a final tickle. The basic shapes are about right, but there's a lot of fettling and finessing to do (my favourite bit actually). The reason being is that there's no point at all getting a final finish on a panel (assuming I can of course), if it turns out that the basic shape doesn't blend with the adjacent areas, and the shape of the whole is a way off. It's all a bit chicken-n-egg: it's difficult to make a call on the shape until the panels blend together well, but you don't want to invest a large number of hours in the finishing, until you're pretty certain the basic shape is right.
Anyway, as the next area to be tackled is the front wing, so that we can start to eyeball down the whole side of the car, I'll detail this. Any methods I use are simply those that I've been shown either first hand, or via books and vidoes. There are probably many, many ways of approaching this work, some better than others, some worse. It may well be the case that later on I find a better way of doing things, or try something else, only to return to this method.
The first thing I do is come up with a paper template. This is a doddle if you've got an existing panel to work with (perhaps a rough or rusty one), but much harder when coming off of a buck, as you have less to press the paper to. Usually you'll gather up loose areas and tape them, which represent areas that will need shrinking. By the same token, areas that need stretching get slits cut, and opened up.
In this case, I simply pressed the pattern onto the wireform as best I could, and taped up the creases. The neater you can do this the better, but this rather woeful attempt was plenty good enough for this example.
The idea of the paper pattern is that a) it gives you a template to mark around when cutting material, and b) it tells you as much as possible about where shape in the panel is going to fall. The advantage a paper pattern has over and above the jig, is that is doesn't depend on the angle of twist that a panel may have. It'll still fit the panel (and guide you), even if the panel is twisted, propeller style. Often when working with a buck only, you're tempted to just keep wheeling and wheeling, even if, in actual fact, the panel had the correct shape (shrink and stretch), just the wrong alignment.
This can be seen below: the pattern has been placed on the flat sheet, and it's clear just where the majority of wheeling needs to occur, irrespective of the position of the aluminium. It also just shows to what degree the metal needs shifting:
It's even more obvious with the blank placed on the buck: nearly there!
Note that the metal has a degree of grain, and rather like corrogated cardboard, it will take a shape with the grain a fraction easier than across it, although this half-hard ally is fairly friendly in this respect. Even so it makes sense to work with it where possible, and this also illustrates why sometimes someone might cut into a new sheet, rather than use an offcut that at first glance would fit the bill:
To return to the panel: I decided (not sure wisely or not), to attempt it in just two areas. This write up deals with the roughing out stage of the rear one. This area has some challenges: 1) to get the actual curve over the top of the wing to blend into the area head of it. 2) There is a return (reverse curve) all the way down the inner area that will blend into the 'bonnet'. There is another where the wing / bonnet blend into the scuttle. 3) The base of the wing drops into the sill, which obviously curves away underneath the car.
If all of the shapes where put in in one go, the panel would no longer clear the english wheel. Therefore I elected to get the top fitting correctly first, and then will worry about the side / arch and sill areas later.
Pictures of the wireform show the shape:
I'm forming this panel 95% on the wheel, and will just use the flipper for forming the return down the bonnet side. So all of this shaping is being done by stretching the metal. It'll probably end up being one gauge down at it's 'thinnest', but since we're starting off at 16g, we've got loads of meat in reserve. The alternatives might be to form the panel with more parts (more welding as well), or to employ shrinking as well. In this case though, shrinking would have got messy, and in fact I can't really see how you could do this without really needing a load of tidying up later.
Anyway, embryo panel as I left it yesterday. Pattern and cutting out probably took a hour and a half, wheeling to this point around six hours going carefully (better not to wheel enough, than over-wheel and have all the hassle of wheeling shape back out. You can see that the panel is still well off of the wireform (seen at the front here, but in reality it's all round, I'll keeping wheeling out the areas touching the buck until it all sits down O.K.).
The next stages will involve dropping the panel hard down onto the wireform (hopefully!), then blending the shape into the side of the panel. Because of the shape, I'm going to have to put a finish on the panel before moving away from the top (it's very, very rough at the moment, which is fine, the finish starts to come when the shape is very nearly there). After that I'll move dwon the panel to blend it with the adjacent panels, and finally once all looks O.K., form the sill area (if I go that route: it may look better with the sill line going all of the way forward, and the wing sitting on top of the line: we'll see, and both options are well open).
