Following on from last month's installment on dent removal, we thought a further look at some more advanced metal fabrication might be in order. After all, if you're contemplating tackling the bodywork on a steel car, there's a distinct possibility that you'll be undertaking somewhat more-than-simple dent removal.
However, patch panel installations and the such have been covered many times before, and with the increased availability of metalworking tools-such as English wheels (or wheeling machines to use the correct terminology) and power hammers aimed at the hobbyist rather than purely professionals-perhaps a look at how these tools are used or could be of use to you might be more ... useful.
As is often the case, there is usually more than one way to achieve the same result, and metalworking is no different, so bear in mind that the processes shown here are simply the ways in which these guys were taught or worked out for themselves. Some may prefer to use a large mallet to rough out a panel while others might eschew this in favor of forming a panel, from start to finish, on a wheeling machine. No way is any more right or wrong than another, so long as both end up at the same place.
We have tried to stay away from very large and expensive specialist equipment here. However, we have included a large wheeling machine with a cast-iron frame that is not so readily available, as well as a Pullmax machine, which is probably beyond the scope of all but the most dedicated hobbyists. With that said, knowing what can be achieved with either of these two machines is definitely of interest.
Cut It OutBefore forming, bending, or shaping any sheetmetal, it first has to be cut to size or shape. There are numerous ways to do this, from basic hand shears and snips to using a plasma cutter. Obviously aviation tin snips are going to be the cheapest option, and there are some very cheap versions available. We've seen sets of right-hand, left-hand, and straight-cut snips for as little as $12, but it pays to purchase the best set you can afford, especially if you plan on using them frequently. Next up, at least without moving on to electric or air tools, are various forms of shears, from a hand-operated version to a flatbed industrial sheetmetal shear with a foot-operated lever.
There is a great selection of air tools that will cut sheetmetal if you have an air compressor in your shop, from shears and nibblers to air saws and cutoff wheels, though again you get what you pay for. Good old electric grinders with a 4-inch cutoff wheel can be useful if there's no compressed air available.
Finally, the plasma cutter is becoming more prevalent in hobbyists' garages, and is a marvelous way to cut out complex shapes, though probably best suited for thicker-gauge sheetmetal.
Which Dressing?Once you've cut your workpiece to shape, you'll invariably need to dress the edge to remove any shards or splinters, unless you used some form of shear. Perhaps now is the time to mention that a pair of leather gloves can be a wise investment, as your hands won't forgive you for sliced fingers or even metal splinters.
The simplest way to dress the edges of sheetmetal is to use a hand file, though a belt sander is probably the quickest method. Both air and electric grinders with abrasive pads have their place but can remove material from the workpiece as well if you're not careful.