Panel Craft -- News & Views

Repair or Replace | The Essence of Handmade | Metal Shaping Basics

Repair or Replace

Often times collectors/vintage racers are faced with the dilemma of deciding whether to re-body their newest vintage racecar or repair the existing sheet metal panels. If the car has a body made of aluminum it is almost always better to re-body than repair, with a few notable exceptions.

Aluminum, over time and use becomes work- hardened and brittle. In addition, the panels most likely have been repaired and straightened over the years; this also hastens the process of work-hardening. If the panels have been repaired, someone used a file to metal finish after the panels had been planished smooth. If done improperly this can shave .030 to .040 from the surface of a fender. Couple this with the fact that the substrate has corroded and absorbed forty plus years of road debris, brake dust etc. etc. it becomes virtually impossible to weld.

Taking all these points into consideration the decision to re-body becomes an easy one. However, there are some things that you should be on the look out for when you choose a shop and commence work. First, insist that the individual blanks, which are cut and shaped to make up a completed fender, are as close to the size and shape originally used. This guarantees that the seams are placed where the original coachbuilder had intended and, goes a long way towards assuring that the fender or roof section has the shape it was originally planned to have. Second, make sure all the proper fasteners are used. Never use a pop-rivet where a screw was or, a solid rivet in place of a screw. Third and most important, never ever tig weld body panels! If the shop insists on this method of welding they do not have the experience and know how to fabricate an aluminum body. Insist that you want the panels flame welded- end of discussion.

Now for the few notably exceptions. If you're the proud owner of a 59' Ferrari Tessta Rossa with a Fantuzzi body or a 36' Delahaye done by Fagoni And Folaschi you would not want to re-body unless the original is burned or battered beyond recognition or the body is missing altogether. These are cases where the notoriety and artistry of the original coachbuilders met or exceeded that of the manufacturer and should be preserved at all cost.

The Essence of Handmade

Recently there has been a resurgence of interest in "handmade" cars. The reason for this growing awareness can be attributed to the many shows seen on television highlighting shops and individuals building custom cars and motorcycles. Traditionally, when I think of handmade cars my mind conjures up the image of the great Carrozzerias of mid 20th century Europe. These companies and the artisan-craftsman they employed produced some of the most stunningly beautiful automobiles ever to roll on four wheels, using nothing more than rudimentary hand tools. Today, this is not often the case. What we are seeing now is often times vehicles which I would call "hand fitted". You could define hand fitted by saying that a person accumulates all the pieces necessary to do a build and then modifies them, some quite heavily and assembles them to form a completed car.

To best illustrate my point I will draw on the example of Lance Reventlow. In the mid 50's Lance was a young man in his twenty's who just by chance was heir to the Revlon fortune. Because of his circumstances, he found himself with unlimited time and resources to pursue his interest, one of which was motor racing. Lance being a California boy thru and thru knew there was only one choice when it came to American racecar builders, and that was Troutmann-Barnes racing. Armed with the design expertise of Ken Miles the team of Lance Reventlow, Dick Troutmann, and Tom Barnes were able to develop and build a chassis for his new American Special, which would come to be called the Scarab. Once the final design for the chassis was approved and work began Dick Troutman walked down the road to see his old pals at California Metal Shaping. With nothing more than sketches and rudimentary dimensions Emil Deidt and Company cranked out one of the most outrageously beautiful racecar bodies ever built, the rest is history.

In my mind all the individuals involved in the construction of the Scarab were artisans of the highest order. They were able to build one of the most successful competition cars of its generation using very basic hand tools and machinery. In their hands, the tools and equipment were brought to life and an Icon was born.

The Basics

To learn metal shaping it is best to start with a few basic tools such as a shot bag, a wooden bossing mallet and a large tree stump with a dish shape carved in the middle approximately 6" in diameter and 3" deep hollowed into the center. The log should be about 24" in diameter and height, (you can place the log on a pedestal to your desired working height). The hammer and shot bag can be purchased from a company such as U.S. Industrial Tool and Supply Co. or Eastwood. It is best to begin with hammers and shot bag because the beginner can better control the basic hand tools. You are now ready to start.

Select a piece of aluminum or steel about 15" in diameter. Now using the blunt end of the wooden bossing mallet and the hollowed shape in the top of the log you can begin shaping your panel. The tree stump is used to quickly bring shape into a panel so don't be shy about hitting it. Hammer a shape 3" in depth and 12" in diameter into the center of the circle. Now proceed to the shot bag and slowly work out any gross imperfections. When this is accomplished, return to your tree stump and using the flat part of the log surface, you can begin to shrink the outer 1-1/2" of the dish. The shrinking process is best described as a gathering procedure. You will notice that the outer portion is wrinkled while the center section has a somewhat "drawn" appearance. The inner section of the panel is stretched from the hammering while the unworked outer portion is showing a series of undulating "V's". What you will be trying to do is increase the thickness of the metal by forcing the little V's in against themselves. Lay the edge of the panel on the flat portion of the log so that the wrinkled portion loosely resembles an inverted vee. Take your rawhide or wooden mallet and strike the top of the vee with a quick blow; this will cause the metal to increase in thickness thereby shrinking the edge of the panel. With a little bit of practice you quickly learn how to stretch and shrink metal. Just remember to go slowly and try to think about what is happening to the metal with each blow of the hammer.

It is best to begin with these techniques because the novice can gain a real sense of accomplishment with a relatively small amount of expended energy. Remember to try to think of the metal as modeling clay because the two mediums react exactly the same way to applied mechanical energy.

Panel Craft LLC
Bethlehem NH 03574
TEL 603-869-5535
stafford@panel-craft.com