Removing rust with Molasses

[cc_bob]

Thought I'd put this up to show how I remove rust from sheet metal, I didn't come up with it old timers use it to clean engine blocks.

Benifits...

• It's non-toxic
• Cheap (especially if you buy in bulk)
• Doesn't remove any metal (acids and blasting do).
• Won't warp your parts
• Doesn't require a battery charger or electricity.
• Easy, just set your parts in and wait.

Drawbacks...

• It takes a week or two to remove all the rust.
• It has a sweet smell (smells like wine fermenting) but I kind of like it.
• It doesn't work as fast when it's cold but that doesn't matter because I don't either
• It will not remove grease or paint unless the paint is loose.

Here's what you do...
1) Get some FEED GRADE (sulfated) molasses, this is the type sold in feed stores. The kind you buy at the grocery stores for cookies doesn't work. TSC carries this brand but your local feed store should have it cheaper(brand doesn't matter).


2) Find yourself something that holds water and is large enough to submerge your parts. I use an old 275 gallon fuel oil tank laid on it's side.


3) Mix 1 part molasses to 9 parts water. Depending on how big your tank is you might want to buy in bulk from a feed store. Our local one is $0.16 lb if you bring your own container.

4) Submerge your parts completely making sure they are not laying flat on the bottom.

5) Wait one week, remove from tank and either pressure wash or scrub with a scotch bright and rinse off the film.

6) If needed, place back in tank and repeat step 5.

7) Clean parts with some phosphoric acid, I use Prep N Etch from Home Depot (concrete cleaner). The acid will remove any flash rusting and protects the part from rusting for a while. It will also convert the rust to black ferric phosphate (aka, kills the rust).


Here's what it looks like after sitting for one week, this was before I had the large tank and I could only fit half of the fender in the kiddy pool I was using. Sorry, I don't have any pics of cub parts but you get the idea. This fender was not painted brown, it's all rust so it makes a good example.