November 2000 Technickel Tips  My 5 ¢ worth  By O. Pinion and his faithful dog Ringgear

November 2000 Topic: Battling the Rust Monster  In the antique auto restoration game rust is the eternal enemy and finding effective ways to vanquish the evil *Rustolamite is the Holy Grail of the crusade.  *Rustolamite is the element responsible for sneaking in and turning all  ferrous metal a reddish brown color every time your back is turned.  (Rustolamite was discovered by that intrepid explorer Duck Dodgers  who, by the way, also discovered the rack & pinion molecule)

In our ever vigilant search for better ways to de-rust Model A parts and thanks
to the magic of the internet we have discovered an effective, inexpensive and safe method for removing rust from parts. It would also work for fenders, etc. but would take a pretty large container.
This method was explained on the Rodders RoundTable website by a street rodder (we won't hold that against him) named Steve Knickerbocker.

                                           Electrolytic De-Rusting Process

The process by which rust forms is electrochemical in nature so this method employs a reverse current flow in an alkaline bath at a higher voltage to reverse the process at a quicker rate.

There are actually two forms of rust: iron III oxide or red rust (Fe2O3) and iron II oxide or black rust (FeO). Black rust is a smaller molecule. The electrolytic process converts red rust to black rust and in the process the black rust becomes weakly bonded to the base metal. The black rust that takes the place of the red rust can be easily wiped, washed, or brushed off leaving rust free base metal. Any pitting that has occurred will remain, this method will not repair damage, but the pits will be rust free.
 

Supplies needed:        - Battery Charger        - Some metal to use as an anode        - A non-conductive container of          suitable size        - Sodium Carbonate (washing soda)          or Sodium Bicarbonate (baking soda)        - Some bits of plastic, such as coffee          can lids,  to use as insulators        - Water

Washing soda can be found in the laundry section of the supermarket, probably Arm & Hammer brand.

The container can be any kind of plastic receptacle. I use an 18 gallon Rubber Maid brand tote.

The anode can be any kind of scrap steel or iron. Stainless steel may be best because the anode gets consumed in the process and stainless will last longer. The larger the surface area of the anode the better.

Fill the container with enough water to cover the part and pour in a good quantity of soda. The more soda, the faster the process. Submerge the part to be de-rusted. Attach the battery charger negative clip to the part. Put the plastic insulators under and around the part as necessary so that it doesn't short-circuit to the anode. Connect the positive battery charger clip to the anode, above the liquid. If the clip is in the solution the clip will be consumed like the anode.

Now, plug in the battery charger and watch the ammeter. Switch to the highest voltage. If the meter pegs out switch to a lower setting. If the meter show a low charge rate sprinkle more soda in the solution. Keep adding soda until the meter is at ½ to 2/3 of the scale. You will see bubbles forming on the part and maybe on the anode. The bubbles are hydrogen and oxygen so provide at least minimal ventilation.

Let the process run for a few hours or even days depending on the size of the part and amount of rust. Large or oddly shaped pieces may need to be turned periodically. Unplug the battery charger before touching the liquid. There will be a brown scum that forms on the surface of the solution that will dissipate after you turn off the charger and the rust silts out to the bottom.

When the part is de-rusted, remove it from the solution and dry it. Use a wire brush or wire wheel to remove the film of black rust. You will now have bare iron or steel!

The de-rusting solution doesn't wear out and can be reused indefinitely, just keep adding soda and more water as necessary. If you need to dispose of the solution you can water your garden with it. Adds iron to the soil! This is not a hazardous substance, which is one of the reasons I like it so much. ****CAUTION**** If the part you are derusting is painted or has grease or oil or other chemicals on it these will become part of the “soup” and contaminate it. I wouldn’t want to eat a carrot grown in soil that contains dissolved lead based paint.

Larry Seemann
Inland Empire A's