I need a short course on what syling bucks are and how they are/were used. As I understand it, a styling buck can be wooden, a clay model, or even a close to production model without running gear........is that correct? At any point in time, were all 3(are there more?) used in the development of a car? Were wooden bucks used by panel beaters to shape the metal?
On a clay model the "buck" is the structure underneath that the clay is applied to. The clay will vary in depth but think in terms of a few inches or less. The wooden buck is more of an Italian panel beater method where the form is used to define to shape. The panel beaters then make the metal conform to the buck. When the buck has large open spaces that indicates that the cross section shape is very constant. When you see solid wood areas it means that the shapes are transitioning. As for the older Ferraris the shapes were not developed in full size clays. Jeff
It's a common misconception that a wooden body buck is used as a form...over which the metal is hammered until it's the correct shape. In actuality... ...the buck is used as a guide (as mentioned above). The panel beater will take a piece of sheet metal...and, well, start beating on it. In the initial stages, he/she will constantly hold the lumpy sheet near the buck to gauge progress...making adjustments as necessary. When the piece of metal is exactly how the panel beater wants it to be, in can be tacked (hammer/nail) to the wooden buck (or, clamped to a wire frame buck). The adjoining piece can be similarly formed and tacked next to the first piece. The seam between the two pieces would be cut straight...and, then, they are welded together. Depending on the panel being created, this process is repeated as often as necessary...a compound curved fender would tend to be made up of more pieces than, say, a door panel. The Italians *generally* used wooden forms and sand bags to do the initial shaping...wooden form being the fabled "stumps," hunks of firewood, or whatever handy piece of wood happened to be the right shape for the purpose (not the same as the wooden buck described above). This gave a very lumpy and wavy piece of sheet metal... Next, the shape would be smoothed and fine tuned. Slapping hammers and dollies were used to smooth the lumps. Various body hammers and dollies were used to fine tune the shape. It's quite a science and most definitely an art...the flatness, roughness, curve, etc. of both the hammer and dolly will affect how the metal reacts. Try it yourself...find a hammer with a flat face...and, whack a piece of sheet metal on a flat surface. Then, find a hammer with a domed face and whack a similar piece of sheet metal on the same surface. An English Wheel and planishing hammer do similar things. The English wheel is usually a flat surface on one side of the sheet metal and a curved surface on the other side. This does the same stretching that a flat hammer/curved dolly would do...sort of similar to the difference between a roller and a tamper to compact the dirt in your yard...same result, different methods. The planishing hammer does what the slapping hammer and dolly do...smooths a worked surface. That's a very generalized description of panel beating...there are many additional steps, depending on what material is being formed (e.g., aluminum work hardens and becomes brittle as it is hammered...it must be annealed periodically).
Dead on. It's also very important to anneal aluminum before you shape it with the shot bag. A wheel is not necessary for most shaping but it certainly comes in handy. It will quickly planish out a piece that has been rough shaped and is excellent for creating panels that have very large, subtle crowned surfaces. Some coachbuilders also made forms out of stel rod called "mannechinos" (sp?) but wood was the predominant material early on. I have to check some reference material but I find it hard to believe that all Italian coachbuilders didn't use the wheel. Perhaps early on but it wouldn't make sense not to use such a valuable tool. I certainly might be wrong on that account having not been there. A buck as used in a full size clay is simply a foundation or armature for the clay to be based on. Typically it is a wood and aluminum substructure that allows for wheels to be mounted so that it can be "wheeled" around followed by a build up of foam. The clay is actually not more than a few inches thick and is applied by smearing it on by hand when it is hot. It can then be used to pull molds or 3d data as well as actually being dynoced or primed and painted. In school we just shot our clays with automotive primer and painted them. They would dent with a fingernail but it was quick, easy and looked dead on. Even with all the computer milling and cad/cam capabilities that exist today the final touch of the clay is always done by the human eye and hand. That "perfect touch" that an experience clay modeler can do by hand still can't be replicated by a machine just yet.
And that's a very good point. An English Wheel is traditionally used to stretch metal by forcing the sheet between a curved and a flat roller. It CAN be used to shrink metal that is wavy...by using two flatter rollers that are not "pressed" together. One can also use non-traditional materials for the rollers (rubbers, urethanes, etc.) for various effect. So...it really comes down to what is available and what is being done. High production vehicles can justify the expense of large dies that stamp body parts. Extremely low production vehicle bodies can be made with nothing more than a few hammers, dollies and a halfway decent OA torch. Medium production vehicles can justify more expensive equipment like English Wheels and pneumatic planishing hammers. There is no "right way"...
I recall an AQ article of many years ago entitled something like "Confessions of a panel beater" that gave a very good description of the process. EDIT: Vol 16 #1 My life as a panel beater by Percival Talman
Miltonian posted some photos of panel beaters in Marcel's Carrozzeria Vignale thread: http://www.ferrarichat.com/forum/showpost.php?p=138277818&postcount=158 The crafstman first rolls the piece of sheet metal to introduce the proper curve in one direction. In the next photo, he is beating the panel with a wooden mallet over a "stump." This is to introduce the compund curve. No English Wheel used in this case. The panel then would have been planished smooth (slap hammer/dolly), trimmed, and probably given a rolled edge for strength. All can easily be done by hand...and, judging by the photos, probably was done by hand. Another interesting thing seen in the photos is the apprentice...the kid holding the side of the panel while the craftsman hammers. Not only was panel beating a two person job...that was how they trained the future panel beaters.
Here is a pic of the ATS buck, taken at their factory soon after they closed down. Image Unavailable, Please Login
I remember seeing a buck for a GTC at the Pininfarina factory in about 1968 but I haven't the photo's - sorry! I think the English wheel was not used at all in the Italian workshops, they would have used mechanical hammers to achieve the panel shapes for the series built cars. I have a 250 PF and although I would like to think the body would have been beaten out by hand, I am sure a lot of mechanical help was used. I would love to see period pictures if anyone has any!
A related, and equally subtle, black art of bodywork is using lead / metal body filler. I've seen it done and, in the hands of a professional, it is nothing short of amazing.
Here is a little info: http://www.focusauto.com/Station_Bucks.html http://www.focusauto.com/hammer_form.html
Another rare photo from the ATS factory. I think you have more photos at the factory than anybody. Did you ever happen to take any ATS race team photos??Thanks Ed!!! Tom Tanner/Ferrari Expo 2010 model/photo contest-Chicago April 2010
