Rust removal from table tops

[HowardH]

Like a big dope, I left a towel that I thought was perfectly dry (it wasn't.  ???) on the top of my SS.  Now there is a dark stain that is driving me crazy!  What's the best way to remove stains from a cast iron top like this?  I don't want to use 0000 steel wool as it will mess up the finish.  Ideas? 

 

[Sparktrician]

Like a big dope, I left a towel that I thought was perfectly dry (it wasn't.  ???) on the top of my SS.  Now there is a dark stain that is driving me crazy!  What's the best way to remove stains from a cast iron top like this?  I don't want to use 0000 steel wool as it will mess up the finish.  Ideas?

Well, then, forget using the RAS...  [scared]

 

[miclee15]

You'll get a lot of "its a tool" remarks on other boards, maybe here as well, but I like to keep my table top as clean as possible as well.
You can get some very fine grit wet dry sandpaper, 600, 800, 1000, etc....  along with a orbital sander or sanding block, I've done it with a rotex, hahaha.  you can get it to a mirror finish if you choose to.  Just make sure you go even with the pressure to keep it level and not wear out any section too much. 

 

[ChuckM]

How big is the rust spot?
https://www.leevalley.com/en-ca/sho...shing/67014-autosol-metal-polish?item=54Z1510
https://www.leevalley.com/en-ca/shop/garden/garden-care/tool-maintenance/10509-rust-erasers

I'd spray a little WD40 as a lubricant if using the rust erasers.

 

[Stan Tillinghast]

Evapo-Rust should work for that.

 

[rvieceli]

Believe you should call SawStop customer service and see what they suggest.

I would not recommend any method that involves removing material from your saw top to get the stain out.

while it may be an annoyance, you can also look at it as a valuable reminder to not do THAT again.  [eek]  [scared]

Ron

 

[ChuckM]

I've removed rust from my SawStop several times over the years with either of the products I quoted in my previous post, and as expected, there has been zero effect on the table saw itself or on the quality of cuts. Removing rust from a metal surface of a machine (my jointer and band saw table) or tool (handplane, chisel...lots of experience there too) is done by woodworkers all the time around the world.

 

[rvieceli]

[member=57948]ChuckM[/member]

all right I ordered some. We'll how it does on my 1969 Powermatic 66 table saw top. It came out of a high school shop. Top is smooth and flat but has a couple of stains.  [big grin]

Ron

 

[ChuckM]

Don't forget those before- and after- photos! [smile]

 

[rst]

I keep an old PC 4.5 x 4.5 sander in cheap Plano tool box with all the grafes of conditioning pads available to kepp my cast iron tops slick.  I know there are  lots of higher tech solution to keeping tops rust free but I go low, low tech.  I heat my top with my heat gun and then rub the wifey's old scented candle wax over the warm top and then go over with the white conditioning pad...it's work for me over 30 years in am unheated central PA shop.

 

[HowardH]

Don't forget those before- and after- photos! [smile]

Good idea!  I saw a video where the guy simply sprayed WD-40 on in and used extra fine scotchbright.  He used a block of wood and simply went front to back several times.  It seemed to work out pretty well.  Any rust is very superficial and came right off.  It just left a stain. 

 

[Sparktrician]

You could use a RO sander (no vacuum) with a hard felt pad and one of the MPA polishing compounds.  Start high in number and back down as necessary.  Just an afterthought... 

 

[jeffinsgf]

I've used both the products Chuck linked extensively.

Autosol is one of my favorite maintenance/restoration products. It is minimally abrasive and very fast.

The "rust erasers" are from Klingspor. The medium grit is what Lie-Nielsen uses on their demo tools at shows where they're handled by thousands of people all day, with the attendant acid and grunge. If you've ever seen a demo tool at a Lie-Nielsen event you know every one looks like it just came out of the box all the time.

The rust erasers are a little messy to work with if you're going after a serious bit of rust (I've been restoring some vintage machinery lately). They break down leaving a gritty residue. The mess is worth the effectiveness in my book.

 

[Birdhunter]

My trick is to put an 80 grit disk on my RO sander and cut a green and a white Scotchpad big enough to overlap the sandpaper about an inch. I spray the stain with WD40, let it sit for a while, and then “sand”. Start with green, wipe clean, spray WD40, and sand with white. The 80 grit paper holds the Scotchpad pretty well. Don’t tilt the sander!

 

[Cheese]

I've always used 3M Scotchbrite pads cut to fit either the Rotex or the ETS EC depending upon the severity of the rust issue. The Scotchbrite pads come in 4 different levels of abrasiveness so it's easy to match them to the application.

Unfortunately, the dark stains never really come out of the metal. They will lighten up a little bit over time and with use.

 

[ChuckM]

If you guys had to use a sander to remove rust, it was probably quite bad. I only had to remove rust spots.

Prevention is the key. I use these:

Fluid film or CRC 3-36 (after wiping the surface with WD-40). In winter, humidity in my shop (garage) hangs around between 60% & 80%, depending on how often we have snow.

Hand tools: Moovit oil &https://www.leevalley.com/en-ca/shop/tools/workshop/tool-maintenance/53828-silica-gel-dehumidifiers

 

[Peter_C]

So many power tools to use?

I would use a simple wire brush by hand.

 

[Michael Kellough]

I've always used 3M Scotchbrite pads cut to fit either the Rotex or the ETS EC depending upon the severity of the rust issue. The Scotchbrite pads come in 4 different levels of abrasiveness so it's easy to match them to the application.

Unfortunately, the dark stains never really come out of the metal. They will lighten up a little bit over time and with use.

This has been my experience too but I’ve never tried the Autosol polish. Hope it works.

My tablesaw surface is very old (Walker Turner old) and closer to graphite grey than silver so I only have to worry about rust. Plain old hard drying paste wax prevents that.

 

[Birdhunter]

My cast iron table tops develop stains and flash rust if you look at them sidewise. The sander with Scotchpad and WD40 work well.

 

[afish]

Go to home depot and pick up "rust dissolver" made by rust=oleum its in a silver spray bottle and scotch brite scour pads.  I bought a unisaw used for $300 bucks it was in good shape but the guy left it in his shed with no protection on the top.  The top had a thick layer of rust.  I wasnt sure if I could save it.  I bought the rust dissolver and it worked like magic.  I had to apply several times to get it all off but I didnt need to touch it once with any type of sander.  First two coats I put on thick and you have to let it sit.  The rust will start turning black and when the gel starts getting dry I just scraped it off with a putty knife.  It took 2 applications like that, then I turned to lighter applications and working it in with the scoth brite (green) pad from HD the top looks almost like brand new you can still see the factory finish on the top.  I was blown away with how well it worked.  One of the best $10 purchases ever.