A Rust Removal Story


Effects of a Fire


Christmas Eve 2005  The unit next to mine caught fire due to a fault with a wood stove.  The unit housed a carpenters shop and with the amount of fuel in there a fire ball soon started moving through the other units.  Mine was one of them.

The result was the loss of the whole unit including the engineering workshop and all items in it.

     

 

Victim of the Fire


This vice was on the main work bench when the fire went through.  After the fire it was found on the floor having fallen from the burning wooden bench top.  It was thrown outside with the other rubbish and went un-noticed for the next 2 and a half years.

When I was looking for an item to run the test on this seemed the ideal example.  It was completely rusted and the screw and slides had seized due to the  fusing action of the rust on the bearing surfaces and would not move even when some persuasion was applied using a hammer (scientifically of course).  
Beginning the Test 

I decided  to start the test be using a small wire brush to remove the loose flakes from the half of the vice that would be in the solution so the test would show a before and after. 

In the Tank

The solution was made up with 1 litre of concentrate and 10 litres of de-ionised water.  Turning the vice up side down allowed more coverage of the area I wanted to display as an after effect.  The test time was 12 hours overnight  without removal.

First Look

Taken from the tank and brushed over with a plastic kitchen brush to remove the sediment from the metal exposing the test part free from rust and ready for finishing.  


At close inspection you can see that the base mental is not attacked and only the rust has been reduced to a black sediment in the bottom of the tank.  This finish will take any paint or other protection coat to preserve the vice.

 
The first test now over the vice was replaced in the tank and the solution level increased to cover the whole of the vice.  The process was changed slightly with the inclusion of  a heater unit to raise the temperature to 34oC in line with the advice on the makers bottle

      

With the temperature increase the action also increased and the bubble coat on top of the tank was quite energetic.  The removal of the rust was accelerated as could be seen from the occasional lifting of the vice from the solution.
After the de-rusting cycle the vice was removed from the solution and scrubbed with a stiff scrubbing brush to remove any residue left by the chemical reaction with the rust.  This residue appears as  black deposit which comes away with ease when rubbed or otherwise disturbed.  When dry this left a perfect base for painting but before painting and to ensure that no rust spores were left, a coat of Fertan was applied.      
                The vice was painted in the old RECORD blue to match some of the replaced machinery that was lost in the fire and needed to be purchased new. The vice screw is as smooth as before without any binding or undue looseness due to the removal of the rust.