rust stain remediation on my table saw

[Thomas L Carpenter]

My table saw has been living unused in a garage for two years and developed several small rust spots and stains that I would like to remove now that I'm in a position to use it. I read in a local woodworking forum of a guy using a random orbit sander and 180 grit paper to remove all the stains on his saw. My question here is is that a reasonable approach to remove the stains. I've used WD-40 and 4 ought steel wool to remove the rust but the stains remain.

[Lee Schierer]

I usually use Scotchbrite pads to clean off any rust spots. Followed by a coating of paste wax. The dark stains remain. More aggressive abrasives used to remove the stains are likely to change the surface flatness of your table top.

[Mike Stelts]

Some stains are deep enough that I try to think of them as historic beauty marks.

[John Kananis]

Haha, I too. The top of my unisaw looks like a battle was fought there. It's flat though.

180 is way too aggressive unless there's serious pitting. Green scratch pad will address most rust. If it's pitted and you have to use sand paper, I would start with 220 and do it by hand with flat sanding blocks and some type of lube, wd40, kerosene, etc. Work your way up from 220 or don't, up to you. If the pitting is so bad that this doesn't work, then go to a lower grit and if that still doesn't work, then go to a hand held machine and be careful.


Some stains are deep enough that I try to think of them as historic beauty marks.

[Michael Burnside]

Use WD-40 and one of these (maroon scotchbrite pad) on your RO sander. Let the WD-40 soak for about 15-30 minutes. If it doesn't come out and you can't feel it on the table with your finger, it's a character mark as Mike mentions. I would never risk pitting or gouging the surface using anything more aggressive.

https://www.amazon.com/gp/product/B0002SQYF0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

[Frank Pratt]

Use a scotchbrite pad just to smooth out the roughness and apply wax. The stain is there for good.

[Bill Dufour]

In theory a paste of EDTA will derust the stains. But I would expect rust on the edges of the paste. Even if it neutralizes all the rust the base metal will be darker as the carbon is not affected by edta.
BilLD

[Doug Garson]

I don't get the obsession with the appearance of a cast iron table top. If the workpiece glides over the top with minimal resistance it's good to go. It's a tool, not a piece of fine furniture. My 2 cents worth. :cool:

[Albert Lee]

You don’t have to sand or scotch brite it.

I had similar issue with my table top and I used Autosol rust EX and the table top is like new. 506969506970

[Cary Falk]

I usually take a razor blade and scrape off the rough stuff and then polish the top with Scotch Brite and then wax. If the top is real bad you can soak some paper towels in Evaporust and cover the top for 12 hours or so. Barkeepers Friend will kind of bleach any dark spots left by rust. Sandpaper is to aggressive.

[Curt Harms]

You can get scotch brite pads for random orbit sanders. (https://www.amazon.com/s?k=scotch+brite+pads+for+orbital+sander&crid=198Y1FLC0UIZK&sprefix=scotch+brite+pad%2Caps%2C97&ref=nb_sb_ss_ts-doa-p_9_16) I don't think I'd go with anything more aggressive personally. As stated above, as long as wood slides across it smoothly, why risk creating an uneven top with sand paper?

[Rick Potter]

There are sweat drop stains on my Unisaw which were wiped up minutes after being dripped. The saw has never had rust, but those marks are old enough to vote.

[Michael Burnside]

There are sweat drop stains on my Unisaw which were wiped up minutes after being dripped. The saw has never had rust, but those marks are old enough to vote.

LOL, I have a few of those too! Also one fingerprint. At least with the latter, if anyone steals my saw, I can prove it's mine!

[Mike Wilkins]

ScotchBrite and WD40 worked for a rust stain left behind from a cold soda that I mistakenly left on the table top. Removed the rust but a round reminder was left behind. Still remained flat.

[Bill Dufour]

I see no real difference beyond 240 grit paper in a ros. I have gone as far as 1,000 grit maybe 2,000.
Johnson's paste wax is no longer made so results may vary. I used something that was brown and it made the cast iron look dirty.
Bill D

[Curt Harms]

I see no real difference beyond 240 grit paper in a ros. I have gone as far as 1,000 grit maybe 2,000.
Johnson's paste wax is no longer made so results may vary. I used something that was brown and it made the cast iron look dirty.
Bill D

SWMBO liked the 'crystal clear' bowling alley wax sold by Woodcraft for furniture. It seemed to work okay on cast iron tops as well.

[Bob Jones 5443]

No one’s mentioned white vinegar, so I’d think it’s an urban legend if I hadn’t seen it work under my own hands.

I had to store my machines in a garage open to the outside air in a foggy, cold part of the Bay Area in 2016 for about eight months. When I was able to move them, I was horrified to see the cast iron tables of my Unisaw, drill press, and jointer badly rusted. I could feel the damage as I ran my hands over the affected areas: the bright orange spots were rough, and the rust came off on my skin.

Frantic for a solution, I read something that said vinegar will do the job. So I scoured every surface with Scotch pads and the vinegar, rinsing and wiping frequently. It wasn’t easy, and it took major elbow grease and a lot of faith, but my machines came out rust-free, as they are to this day. A few color spots — vestiges of the oxidation — can be faintly seen today, but everything’s smooth, without surface pitting. I suppose the gear visually aged a bit, but everything’s physically intact. Wood glides over the waxed iron.

White vinegar, who knew?

[Jim Becker]

A mild acid like white vinegar has a lot of uses, Bob. Some of the commercial rust removing products use acids, such as the Boeshield product. (It is the largest ingredient in home made weed killer, too)

[Thomas L Carpenter]

Thanks all. I've decided to go with the purple pad (primarily because that's all I have) and wax. The small rust spots were surface only so the saw top feels nice and smooth and looks like a war zone. Next stop is the jointer.