Rust Removal and Cast Iron Restoration
Household items that are severely rusted such as cast iron patio furniture or lawn ornaments can be cleaned and reused. That very old cast iron frying pan or stew pot can be cleaned inside and out right down to the bare metal using this product in preparation to being restored.
Naval Jelly for Rust Removal
Naval jelly is commercially referred to by general names such as rust killer and rust remover. The chemical name this product is "orthophosphoric acid." Phosphoric(V) Acid (Naval Jelly) is quite corrosive and will quickly burn your skin on contact so always wear rubber gloves, eye protection and splash-wear (rubberized apron, etc.) including foot guards to direct any spill away from your skin when using this product. Be sure to only use it outdoors in fresh air or in an open-air shop (garage door up, etc.)
Avoid using this product in any confined space or around any ignition sources such as natural gas hot water heaters or clothes dryers, any source of open flame or heat source (electric floor heaters, etc.) And not least of all, no smoking near where the product is being used.
Using Naval Jelly for Heavy Rust Removal
Removing as much heavy rust as you can with a wire brush is the first step. Using naval jelly will greatly aid your cleaning and rust removal efforts if the heaviest oxidation and any loose flakes are scraped away first
Wearing protective gear, apply the naval jelly product directly to the surface to be cleaned. The product usually includes an applicator spatula for this purpose. Be careful to not spill the product on surfaces not intended to be cleaned. A plastic drop-cloth would be a good item to have on hand. A discarded shower curtain makes an excellent drop-cloth for such occasions.
Allow the naval jelly to sit on the rusted surface for 5 to 10 minutes. No longer than this because it will begin to dry-out and it will also begin to eat the metal if permitted to sit long than 15 minutes. Some chemical heat will likely be generated during use of this product.
Next, thoroughly rinse the item with clean running water. Complete rinsing is required to halt the oxidizing action of the phosphoric acid gel. Allow the item to fully dry from the water rinse.
If there are remaining rusted areas, a second treatment can be used again, maintaining the 5-10 minute maximum time. Do not use this product on painted surfaces for it will quite effectively remove the paint. This product should not be used on stainless steel either.
Naval Jelly Rust Remover and Automotive Body Repair
Naval jelly is often used on automotive restoration projects to remove rust on bulkier items such as engine exhaust manifolds and engine blocks. Here, the intended item is restored easiest off vehicle.
Another advantage of this product is that is supplied in a thick gel-like form which can be applied to vertical and slightly overhead surfaces where it will still cling and provide rust-removal if cleaning/restoration is done while still on the engine.
Coca-Cola also Removes Rust?
Phosphoric acid (of the organic kind) is commonly added to Cola beverages (notably Coca-Cola and Pepsi) for that tart bite quality, and it too works as a rust removal agent albeit much slower. Placing a liter or two of Coca Cola into a rusted gas can or soaking rusted items in a vat of Coke (such as pliers, lawn and hedge shears, hammer-heads, etc.) overnight will greatly de-rust the item too.
Other excellent applications for naval jelly would include gardening equipment such as shovels, hoes, bicycle frames, garden-tractor tilling blades and the like.
Naval Jelly Only Removes Rust, Does Not Prevent Rust From Reoccurring
Naval jelly is not a rust preventative; will not stop rust from reforming. What it does is oxidize the rust to convert it back into base metal which can be controlled with other rust-proofing methods. The treated iron will have a dark black color similar to what happens when cleaned metals are 'pickled' such as in the 'bluing' on shotgun and rifle barrels. There, after pickling the metals are coated with fine machine oils to prevent rust from forming.
In the case of lawn furniture and ornaments, primer and all-weather paints would be used. The naval jelly if applied effectively and thoroughly will have removed all oxidation in the metal and thus no rust should re-form under the painted and/or sealed surfaces.