Tanks and rust. That is not a nice combination. There are many, many smart and / or high-tech solutions for removing rust from tanks. The solution with the tank and a few hands of gravel or nuts on a cement mill is known. And a cement mill? Well: go and talk to the local contractor or Boels.
Mechanical rust removal is possible
A motorcycle shop where the craft genes are still cherished, has made a construction revolving around three axes. As a result, the secreted filling touches all corners and holes. Result? A spotless tank!
But it can also be much easier. With a handle in the kitchen cupboard. There is baking soda. That is a leavening agent for bread. And who doesn't make his own bread these days? So the kitchen cupboard. And then?
Electrolytic rust removal. Child's play
Then the battery charger is removed from the shelf and we get going. With the electrolytic rust removal of the tank. And what do we need - apart from that rusted tank?
A direct current source (battery, battery charger, ...)
A piece of cable
Water
Soda (ordinary baking soda, NaHCO3)
A shelf
A piece of metal.
400 gram citroenacid (drug store)
E95 / E10 resistant coating or two-stroke oil
The manual
Attach the cable to the plus (red) and minus (black) of the DC charger or battery. Take a board and a piece of iron that you no longer need. Make a hole in the board and fix the piece of iron so that it is stuck. Dissolve 100 grams of soda in warm water.
Fill the tank to the brim with the soda solution and with plain water. Place the tank on a few wooden blocks, or on another non-conductive surface (wooden table an inverted wooden box or something). Put the piece of iron in the tank. Make sure that the piece of iron is as deep as possible in the tank, but it must not touch the tank anywhere. Otherwise a short circuit will occur!
Watch for short circuit
If everything is good, everything is securely attached, so that the piece of iron or board cannot accidentally shift during the electrolysis and you still get a short circuit. Make sure that the board 'floats' above the tank, so that junk or water can come out during the electrolysis. Connect the cable that you have connected to the charger to the positive pole to the piece of iron in the board. You must have a bare piece of tank (not painted). For motorcycles, the gas tap is great for that.
You can now switch on the charger. You can choose how many volts (use at least 12 V). The higher the current (Ampère), the faster it works. Results should be visible after an hour, but for complete conversion of the rust, assume only 24 hours or more. When you think you're done, let the water run. The rust has all gone to the piece of iron or turned into a black precipitate.
Now fill the tank completely with water again and add to this (for a tank of approx. 15 liters). the 400 grams citroenacid. You can also use cleaning vinegar. Eg. Fill 3/4 with vinegar and 1/4 with water. Leave this for at least 24 hours.
After very good rinsing, the job is done. Please note, your tank will immediately rust again. After rinsing you should immediately apply a coating or throw a half liter of two-stroke oil in your tank, so that the metal is protected.
Ok, a little lesson in electrolysis:
There is indeed a big difference in the use of baking soda vs washing soda, but the effect is the same in the end…
Washing soda (pH 11), for example Crystal Washing Powder, which you can get at the AH for a few cents, is really much faster than Baking powder (pH 8) due to the much higher pH value, and saves a lot in energy consumption in the long run and is also cheaper than baking powder.
Nor should it be necessary to citroenuse acid or vinegar.
(If you would like, it is much wiser to first fill the tank with Sodium Hydroxide: NAOH, this will remove all excess oil within an hour at most, before you start the electrolysis process)
The use of CitroenAcid, Vinegar and Lye will have an impact on the steel if left in the tank for too long.
Just not electrolysis. You can leave the tank for a few days too long to derust. The process will stop automatically.
If you set up the electrolysis process correctly, you only have your baking soda, a piece of metal
and a battery charger (10 amp is fine).
(Note that you use such a stupid battery charger. The new ones with drip function will not work)
Ahh, and of course also important, after the electrolysis process, rinse immediately with cold water and washing up liquid.
Then let it dry (out of the sun) and after an hour or so add the oil and rub in well where possible.
The little bit of rust that develops in the meantime can be wiped off in no time.
hello,
Is it correct if you replace the steel + with a zinc material after the cleaning session, you can galvanize the tank from the inside. Do you turn the + and - around?
do you have experience in this?
Where the minus (black) connected?
If you look closely at the photo, and read the text on a bare metal piece. In this case, they used the fuel tap.
Watch out for hydrogen! You made a small hydrogen generator here, and in a small space that can accumulate and explode just as hard as gasoline vapors in a tank that you thought was empty.
I once desolate a tank with only water and citroenand sour. Leave to stand overnight and then rinse with demineralised water.
On youtube it says everywhere that it is done with washing soda (sodium carbonate) and not baking soda (sodium bicarbonate).
No matter, NaHCO3 is created when you dissolve Na2CO3 in water.
Sodium carbonate (baking soda) reacts with moisture and carbon dioxide from the air, forming: Sodium hydrogen carbonate.