Getting Started: Sheet metal
Unless you buy a brand new body from Year One, Goodmark, or any number of catalog restoration houses, you will likely face body panel and sheet metal repairs on some level. The most common trouble areas like floors, quarter panels and fenders can all be replaced with relative simplicity, but that does not mean it is easy. If you own a car that does not have a vast aftermarket supply of patch panels, you may have to learn how to work some flat sheet metal yourself. You don’t need a full metal shop worth of tools to work sheet metal either, just some basic hand tools can provide the base to make the most of some flat steel.
Basic metalwork– The most primitive sheet metal work is cutting and simple bends. Many repair jobs can be tackled with a few hand tools. The key tools here are a hammer, pliers and a vise. Even a simple carpenter’s hammer or ball-peen hammer work, you don’t have to have specialty hammers. A bench vise can be used to make simple bends, in the place of a brake, you just have shift the panel over for long bends. Using welding bottles and other devices as bucks and dollies to shape rudimentary curves is another basic technique. This is the best place to start, making basic shapes with basic tools before moving on to specialty tools and techniques.
You will need to be able to cut the metal. Tin snips work, but they can be difficult to use and you don’t always get straight lines. A quick and easy method is sheet metal shears, either electric or air-powered. There are pistol-grip and barrel-handled versions, the pistol grip offers more control, but the barrel-handled units are cheaper. These are only good to about 16 gauge, anything bigger just jams the gun.
Moderate level– This is what I call the step-up in metalworking techniques and tools. Specialized tools build on the basic techniques to create smoother bends, curves and more complex shapes. Shrinker-stretcher dies, metal rollers and brakes are pricey tools, but they produce better quality results. Most restoration and custom shops are on this level, and with the right tools, it is fairly easy to attain a good finished product.
One of the first specialized tools you should buy is a bead roller. There are many dies available, from round beads, to shearing dies, and even louver dies, there are so many potential projects in this one tool. Rolling strengthening ribs in floor pans and custom panels are easy. While it may cost more, I highly suggest a motorized version, the hand-crank style can be too difficult to operate by yourself.
Advanced– Whether you are replacing a factory panel or creating a custom shape, advanced tools and techniques take years to master. Most complex shapes are started with a shot-bag (for beating the metal into a rough shape) and polyurethane rounded hammers create the rough design, then finished on an English wheel and planishing hammer. There are tons of tools and techniques in the advanced level, entire books are written about a single technique. A good place to start with recreating shapes is with paper (thin fabric pattern paper works great) and magnets. Folding the paper will show you where the metal needs to be shrunk and where it needs to be stretched.
The type of metal you are working with makes a difference in the technique. Aluminum sheet work hardens quickly (as does most non-ferrous metals) which causes it to crack and split instead of bend. Using an oxy-acetylene torch set to a sooty flame, the metal is heated up and allowed to cool slowly. This changes the structure of the molecules, to loosen it up, making it easier to shape. Working the metal a lot may require several rounds of annealing along the way.
Just a few years ago, buying an English wheel or metal roller took thousands of dollars and a massive shop to store them. Today, you can buy hobbyist-sized tools that fit in the average shop and cost a fraction of their industrial counterparts. The Eastwood Company offers many of these tools and even training DVDs to learn the techniques. Getting started in metalwork can be both rewarding and cathartic. Beating on a metal panel with a hammer is a great stress reliever.
Leave a comment