Auto repair shops, where body repair is carried out, always have a whole set of tools and equipment for repairing dents without painting and straightening the metal. And although serious damage, and even on a large area without the use of slipways (powerful stands) can not be corrected, draw dents in small areas with difficult access from the inside is quite possible. In this case, you need to use a special auto-tool - a reverse hammer, which is a hand-held device, small in size, consisting of a metal rod and several weights freely attached to it. Gears can be the same, and different masses. At one end, the reverse (body) hammer has a hook, and on the other - a lock washer that does not allow the weights to fall off the rod and thereby transfers the impact force to the aligned surface. With the help of a reverse hammer, arches, rapids, racks are successfully repaired, that is, those places that are not accessible from the inside.
A modern tool for repairing dents without painting, as a rule, consists of several types of grippers, which allow using the same reverse hammer to level dents in different parts of the body. Before using it, you need to clean up the metal to the metal to be drawn, drill a small hole in it or weld special repair washers. Then you can fasten the hammer. Further, the operator only has to gradually pull the metal, causing a series of weak impacts until the dent is completely eliminated. Of course, after such operations it is necessary to paint part of the body, but only by this method it is possible to carry out a qualitative repair of some elements of the car. To eliminate oblong dents and edges, it is necessary to weld a few washers, pushing the rod out of the metal through the holes.
In addition to reverse mechanical hammers, there is a vacuum equipment that allows to remove dents without breaking the body coating and, accordingly, without the need to carry out paint and varnish work. Such a reverse hammer has a special suction cup grabbing equipment. With it, you can repair large areas of land. During operation, the vacuum reverse hammer is connected to the compressor to create its pneumatic fixation to the surface by the supply of compressed air.
Remember that you should not use a reverse hammer to level the dents in large areas, such as the central part of the roof, the hood and the trunk lid. Welding of washers can pull the metal too much, the part will become unusable. On sale there are hammers not only with one, but also with several weights, as a rule, two or three. Such designs allow you to adjust the impact force.
If there is no possibility or desire to purchase a ready-made reverse hammer, then you can create it yourself. To do this, you need to buy a stainless or steel rod with a length of 50 cm and 2 cm in diameter, a steel weight (bushing), an ebonite handle and a hook. You can also make a hook by yourself, using sheet metal 4 mm in thickness. If you want to make a vacuum reverse hammer, use a suction cup instead of a hook.