cast iron rust removal

if it’s just light surface rust try sanding it or take a chisel sharpening stone and rub the top with that with alittle oil in between this works great vut I have sanded with a light grit on a jointer and it came up great good luck Alistair

-- excuse my typing as I have a form of parkinsons disease

I use Scotch Brite or Bear Tex on a sanding disk and then use Johnson’s floor wax right away.

-- Never board, always knotty, lots of growth rings

I use the BoeShield T-9 kit (woodcraft #128478) kind of smelly so keep the windows open, but it works great.

-- Todd, Richfield MN

You can also use CLR. I have restored several tools. For light rust, a scrotchbrite pad or steel wool works well. For a little more rust, I use sandpaper and for heavy rust, I use CLR for small objects and electrolysis for large objects. Electrolysis works really well, just takes a while. Just remember to dry it really fast afterwards. Rust sets in real fast. I use a compressor and heat gun for large parts and the oven if I have a lot of small parts.

BoeShield T-9 Rust Remover is great stuff. No scrubbing at all. Just spray on and wipe off. Strong orders (have a fan blowing the fumes away from you). I’ve never seen anything else work as well. I de-rust with BoeShield and then use Johnsons floor paste wax or some other product to get the surface slippery. BoeShield has a lubricant but it’s not very slippery.

-- DaveH - Boise, Idaho - “How hard can it be? It's only wood!”

owwm.com has a great section in their wiki about restoring rusted cast iron tables.

On the old Craftsman table saw I recently restored, I used single-edged razor blades to remove most of the rust. The table was pitted in a few areas and I didn’t want the rust sitting in those pits continuing to grow. So I used a phosphoric acid based product to convert the rust back to base metal. There are many phosphoric based products out there (Rust-B_Gone or something like that). Many people don’t like phosphoric acid because it leaves a grey coating, but I found that came off easily with the next step. Point is, I don’t think leaving rust in the pits, like sanding would do, is a good idea. Also strong fumes, ventilate!

For the next step I used the green plastic scratchy pads (Scotch-brite?) on an orbital sander for final polish. The plastic doesn’t remove as much material as sandpaper, leaves the original machining marks and leaves the cast iron looking like it did the day it left the factory. A little floor wax and the table looks as good as new 1 1/2 years later.

-- "Find out what you cannot do and then go do it!"

Another plus for BoeShield Rust Remover and protector, you can get a kit from Sears also.

Wood magazine put a bunch of protectors/removers in 2004 and Boeshield came out on top. Boeshield provides this link to a partially redacted version of the article. Wood charges $3 to read the whole article here. I’ve read the full version and its not much more than how they tested (soaking each top for 24 hours in a humidifier box).

Note for using the rust remover: Wear gloves, have lots of rags handy, and don’t let it sit too long. This stuff is highly acidic and can work too good if you let it stand.

-- Scott

Another option is WD-40 and sandpaper. I have an old sander that I use for this purpose. Spray and sand with wet/dry sandpaper. I start with rough paper and finish with 600 grit and as long as there isn’t too much pitting, you can make the surface look and shine like glass.

-- Brian, Lebanon PA, If you aren’t having fun doing it, find something else to do.