Is there a dent on your bike's tank? It's okay, it happens, because only the one who does not drive does not fall. But now, after all, the gas tank needs to be repaired, and a lot of rustling pieces of paper will be taken for editing and painting in the service ... But you can do everything yourself if your hands grow from the right place, and at the same time they are no more crooked than the face of the alcoholic Petrovich from the next entrance on Monday morning. You can straighten a dent in the tank yourself! First you need to determine the extent of the damage. If the dent on the gas tank is small, and at the same time the tank itself is painted without any tricks like stickers under varnish or airbrushing, then you can get by with local editing and painting. If the damage is serious, you will have to paint the entire tank. In the second case, everything is clear, but what to do in the first?

First you need to estimate the surface area that will be deformed in the process of straightening the dent, and carefully clean it from paintwork. Probably no one needs to explain how to peel off the paint from a gas tank. Having finished with this, you need to straighten the place of the dent. A reverse hammer is ideal for these purposes - a special device for straightening such dents. It is unlikely that he was lying around in your garage purely by chance, but you can buy it or borrow it from friends. But we are not looking for easy ways! Or, suppose we don’t have a reverse hammer, there’s no one to borrow it from, and the lack of extra finances doesn’t allow us to buy it. Then there is another way, but we need a soldering iron, soldering acid, solder and braided steel cable. Intriguing start, huh? So, it is necessary to strip five centimeters on one side of the cable, unwind it and tin it. It is also necessary to tin the dent on the tank. When done with this, take the cable and firmly solder its unbraided elements to the place on the motorcycle tank that needs to be straightened. Then we begin to apply moderately brute force - we pull the cable, if necessary, pull it jerkily, only carefully, then the cable will not come off the place of the solder. In this way, you will gradually draw out the dent on the gas tank enough so that it can be hidden during the painting process. Only if you still use a reverse hammer, and not all this Kama Sutra with a cable and a soldering iron, do not overdo it.

When finished, remove the remaining solder from the gas tank (if you used the cable scheme), clean the surface, level, prime and prepare for painting. Everything can be painted, first, of course, carefully covering with masking tape all those parts of the motorcycle that should not be accidentally painted.

There are a lot of ways to remove dents on the tank. Someone advises to bury the tank in the sand, pour some gasoline into it and bring a fire to the filler neck: the gasoline will explode and straighten the dent. Someone pours peas into the tank, fills it with water and leaves it until the peas swell and squeeze out a dent. Someone adjusts a ball camera under the dent, and shakes it until it squeezes out the dent. More advanced repairers use a reverse hammer to tame dents.

Today we will go the easier way and try to remove the dent with the help of a compressor: this method is available to almost anyone, fast and quite effective.

As a visual aid, we will present a tank from the usual Alpha. For some reason, almost all Alfs have a tank crumpled from above for some reason.

There are also a series of dents on the sides.

As much as possible - we seal the filler neck. The fastest option is to put a piece of rubber on the neck - put a plank on top and crush it with a clamp.

When we pump pressure into the tank, it will begin to deform and so that the halves of the tank do not part, we tighten the halves of the tank with a rope

We insert a blow gun into the hole of the fuel cock and pump air into the tank

So, given: a heavily dented tank, dents with a tricky profile in tricky places. Task: align to “as it was”, but do not overtighten thin metal. Method: soldering the probe and drawing with a reverse hammer.

Under the cut, I post a description of the method with a photo report on the work done. The author is not me, but, I just combed the report and posted it (he doesn’t mind). You can send him an invite to BP :)

Go…

We drain the gasoline, unscrew the gas valve, the cap and blow the tank with air.

We clean the dent and a little around it with a circular metal brush (such a nozzle for a drill).

This can also be done with an abrasive (sandpaper), the result in any case will be something like this:

... and we are tinkering with the soldering points of the nut on the tank with soldering acid. You can also irradiate the entire place of the dent, if it is small, as in this case.

Due to the lack of special tools and fixtures for tin work, I made a home-made reverse hammer (made in 10 minutes from an M6 bolt, an electrode with a diameter of 4 mm and a weight placed on it, weighing about 200-300 grams).

The trick lies in right choice soldering points. I started to pull from the edges of the dent.

Naturally, having irradiated the surface of the nut to be soldered, we solder it to the right place. I did not use a simple nut, but with an increased area that will be soldered (essentially a piece of a 12 hexagon with an M6 thread).

To prevent the nut from moving from the selected place when soldering, I used an M6 stud about 120mm long.

We solder. We are waiting for the solder to harden. By the way, I used an unknown brand of solder, but it is refractory. It won't melt with a regular soldering iron. Actually, we fasten the reverse hammer to the soldered nut, and start, holding on to the load, tapping the dent. The number and strength of impacts depends on the depth of the dent. When the metal takes its original shape, the nut simply comes off on the blow of the reverse hammer. That is, unlike welding, it is impossible to pull the metal.

The elongated surface can be straightened with an ordinary hammer, preferably through a wooden block. It turned out very well. The solder from the metal is simply brushed off with the same brush nozzle on the drill. A thin layer of putty will smooth out the micro-dimples remaining on the metal. I think for big dents you will need to use a larger diameter nut.

As a result, it turned out like this: