# best way to clean cast iron



## droppedtuning (Jun 21, 2013)

hey guys i am restoring several old industrial carts into coffee tables. my question is how best to clean the cast iron and what is the toughest paint to put back on it. the first one i did with a wire brush on my grinder and it took forever and could not reach a lot of the spots. i am curious about sandblasting them with maybe a cheap harbor freight setup{ for i am out of work} . any experience here with such? also any better suggestions for repainting them other than rustoleum? need some flat black and some maybe clear. thanks guys


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## hoosier0311 (Nov 8, 2012)

It seems to me that sandblasting would be the best/quickest way to get them cleaned up. I would check into having them powder coated when your ready for finish. Not sure about cost of that though. If that is cost prohibitive I would think about any good quality primer and paint should give a pretty durable finish, especially given they will be coffee tables and inside a house.


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## lepelerin (Jan 13, 2012)

To clean I would recommend evaporust.


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## Mosquito (Feb 15, 2012)

If you're using rattle can paint, some sort of Enamel paint would be a god idea. I use Duplicolor Engine Enamel (for semi-gloos black) when re-finish handplanes, works well.


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## CudaDude (Jan 30, 2012)

If you're wanting remove rust, look into electrolysis. Google it. It's cheap and easy. I did a cast iron table saw top and it came out pretty good.

I did a blog on it, but I don't know to link it


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## OSU55 (Dec 14, 2012)

A cheap HF sandblasting kit is worth a try if you have an air compressor that will run it. The de-rusting methods don't clean up the chipped paint etc that sandblasting will. For paint I would use implement paint. I've used some from TSC (tractor supply co) that has held up great and it isn't much more expensive than the typical rattle can stuff. I use it anytime I'm painting metal if I can get the right color.


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## dhazelton (Feb 11, 2012)

If you don't have a massive compressor than you will be quickly frustrated with trying to sandblast things, and if you do have the compressor then you are better off with a cabinet over a pressure pot. Why do you think you need to strip it all down to an 'as new' condition? I would just degrease and paint as is or hit with some clear finish to keep things from rusting further, but maintaining the look of age. I think people want their streampunk stuff to look old, not like it came from HomeGoods or TJ Maxx (yes, I have see repro carts like these in department stores). What is going to happen with the wood - a light sand and varnish?

People clean cast iron pots and skillets in a big tub filled with water and lye, like Drano. Wear googles, old clothes and rubber gloves if you do that - it will take off all grease, most or all paint and possibly your skin and eyeballs. Google around, I think you need to add the Drano to the cold water (don't pour water over powdered Drano or else it will react too quickly and blow up in your face). Soak for 24 hours and have tongs available to pull out your pieces and have a tub of clean water ready for a rinse. Your pieces will flash rust immediately so maybe have an air hose ready to blow all the water off.


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## oltexasboy1 (Sep 25, 2013)

Muriatic acid is also something you can use ,not as expensive as Drano but acts the same way .Use protective clothing. When I was a mechanic we used muriatic acid a lot with good results.


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## AlaskaGuy (Jan 29, 2012)

I sand blasted this cast iron band saw and sprayed it with rattle can "Hammerite" paint. Did this about 15 years ago. Still looks like the day I painted it.


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## BasementShop (Nov 3, 2014)

> Still looks like the day I painted it.


Amazing detail! How did you get visual affect of sawdust into your paint job?!?

{chuckling.} Nice restoration!


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## BillWhite (Jul 23, 2007)

The HF unit that I have is a "soda blaster". Works well with the A & H baking soda. Does take a lot of air, but it does a good job. Just don't be in a hurry.
Prime and paint after the metal is clean.
Bill


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## Dark_Lightning (Nov 20, 2009)

> To clean I would recommend evaporust.
> 
> - lepelerin


Yes, and on cast iron don't use an acid-based process, since if you don't neutralize it well enough, the acid will continue to work into the grains of the metal, making it brittle. There will be a carbon "smut" left after any acidic treatment. There are all kinds of blogs on the internet, and this subject provides a bewildering array of them. Just make sure that all petroleum products are removed, because Evapo-Rust doesn't cut through them.

I did use electrolysis on an old cast iron contractor's saw body and had good luck, but it took a long time. So I shouldn't slam the method, though I used a caustic solution instead of an acidic one. If you leave iron alloys in a caustic solution, you can come back later and find your article. The same cannot be said for leaving an iron item in an acidic solution. You may find nothing but sludge when you come back. That electrolysis process was a complete pain, and I took a risk on damaging my bathtub, even though I had the saw in a tote that I had bought. If I had cracked the spa tub, not only would my wife have been annoyed, I would have had to put in another, which I really don't want to do.


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## Rayne (Mar 9, 2014)

I third the Evaporust method as it is environmentally friendly, doesn't smell bad, safe on the hands (yes, I used bare hands and it was fine), doesn't ruin any finish (unless rust is Under the finish, then of course it'll ruin it), gets ALL the rust off, and can be disposed of in the sewers. Just get a decent size container for the parts, let it soak completely under Evaporust overnight, and you're done. Just wipe it down with water and dry it off. I used the stuff exclusively on my Jointer restore and it's amazing.


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## droppedtuning (Jun 21, 2013)

i have at least 8 of these to do , so i think i will get a hf blaster tank and maybe build a cheap blast cabinet. thanks guys i appreciate it


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## MedicKen (Dec 2, 2008)

Electrolysis…..Why are you ruining the carts?


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## droppedtuning (Jun 21, 2013)

ruining the carts ?


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## mudflap4869 (May 28, 2014)

I build a large fire and put my cast iron skillets in it. When they turn red, all the crap just pops right off. After they cool off, I wipe off any small amount of surface rust and reseason them. This is the way it has been done for centuries. I do the same for other cast items and paint them before the have an opportunity to begin rusting again. No chemicals or sand blasting to breath in. 
Vinegar will also disolve surface rust on cast iron. Leave it sit in a bath of vinegar for 24 hours and the rust should be eaten away by the acid in the vinegar. Non toxic and cheap. It could be black and slimy so you will have to wash it off after soaking.


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## droppedtuning (Jun 21, 2013)

just the wheels alone are 16 inches tall and 8 sets. with all the parts on these carts would take a lot of anything liquid to soak them in


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## TravisH (Feb 6, 2013)

I would believe the previous ruining the carts statement is he likes them that state of decay.

Many find returning them to the state of the finished product in the above photo as going too far. Shiny, perfect is far from goal of the ones I see being sold around here bring more money "restored" to old looking. The scores of the Pintrest Upcyclers relishes capturing the history of the piece. Cleaning them up to the extent of the photo leaves a very sterile piece with no "history" and drops the coolness factor to this demographic. Cleaning it up a little, exposing some of the wood through the paint and then a flat finish, would fetch a few hundred more than the sterile one.

On a purely economical standpoint you will likely make more per hour of your time not doing as much work and leaving them functionally rough around the edges.


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## dhazelton (Feb 11, 2012)

He knows his market - we don't folks. They may all be sold already as cleaned up. Everyone isn't like us, liking things in their working clothes.

Blasting, wire wheel, fire or caustic bath is the only way to get things down to clean base metal.


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## bold1 (May 5, 2013)

I use spray oven cleaner on engine blocks before painting with equipment paint (bought at a tractor supply) and a little added hardener bought at the auto paint supplier. The oven cleaner goes into the hard to clean areas and I wash it off with my pressure siphon gun first with soda water then just water. I have done several over the years and so far the tractors look fine.


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