# how can I restore a cast iron table saw top?



## mjgilm (Jul 27, 2015)

I bought a used Rigid 3650 table saw that had been outside for a little while and was a little rusty. I tried rust removers , but the top was still bumpy, so I used sandpaper on it and got it fairly smooth but still not right. Everything ( fence, miter guage, and material) still wouldn't slide smoothly. I need some professional advice about what I should next. Can anyone help me? It seems like a pretty nice saw.


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## wapakfred (Jul 29, 2011)

I had a friend who bought an old jointer that was badly rusted. All he did was use his ROS on the tables, and they came out looking great.


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## MrUnix (May 18, 2012)

If the cast iron was badly rusted, then re-grinding might be your only option… however, they rarely are that bad off. It would need to be really, really bad to get to that point. Scraping with a razor followed by scrubbing with various combinations of solvents and scotch-brite pads and light sanding should be all that is needed, followed by a good coat of wax.










Cheers,
Brad


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## soob (Feb 3, 2015)

The razor is the key. Get a 100 pack of disposable blades ($4 at Harbor Freight) and a sturdy handle for them. Change the blades frequently as they cut better when new.

If you do decide to use a ROS make sure you do a quick surface map so you don't linger in places that are lower than the rest of the top. If you put a low spot in you'll never get it out.


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## pjones46 (Mar 1, 2011)

+1 MrUnix. I have used his method many times and works really well.


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## MrUnix (May 18, 2012)

For an example of how far you can take it… check out this thread (by Jay Peitsch Sr.) over at OWWM on the restoration of an old C-man saw: http://owwm.org/viewtopic.php?f=1&t=135736

The table started off looking rather ratty:









To looking as good (or maybe even better!) than it did when it left the factory:









(All credits go to Jay)

Cheers,
Brad


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## Nubsnstubs (Aug 30, 2013)

Instead of using razor blades, why not remove an iron from a plane and start removing whatever needs to be removed. It doesn't hurt it. Better yet, leave it assembled and plane off the bad stuff. .............. Jerry (in Tucson)


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## rwe2156 (May 7, 2014)

Here's what works for me:

1. Orbital sander + 180 paper + WD40.
2. OS on top of scotchbrite pad.
3. Rinse with brake cleaner.
4. Allow to dry and apply Boeshield.

I don't worry about bringing to pristine condition, there is no real necessity (but it sure looks nice).

Whatever you do, don't put any rust remover like OsPho on it (now how do I know that?;-)


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## jonah (May 15, 2009)

If the rust is really bad, remove the top and build an enclosure out of plywood and plastic sheeting that'll submerge the thing in water. Then either use evapo-rust or electrolysis. Both are staggeringly effective and quite easy to set up, so long as you can get the thing submerged. You'd likely need ~2-4 gallons of evapo-rust, so that'd be the more expensive route, but you can re-use the stuff forever. Electrolysis only requires water, a car battery charger (NOT an automatic one, the older the charger the better), and a $3 box of washing soda.


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## RogerM (Oct 31, 2011)

Orbital sander + 180 or 150 grit disc. Follow with wax and buff.


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## EEngineer (Jul 4, 2008)

+1 MrUnix

I have refurbished two saws this way.

Sanding, even with 180 grit, removes metal. No, no, NO! On my current user you can still see the original grinding marks.


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## rwe2156 (May 7, 2014)

> +1 MrUnix
> 
> I have refurbished two saws this way.
> 
> ...


It doesn't remove enough metal to be a problem for a ww'ing machine.


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## soob (Feb 3, 2015)

Metal's already being removed when it turned into rust and you scraped it off.


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## Sketchman1981 (Jan 6, 2017)

I'm getting ready to restore the table saw I have. I've never even turned it on (was an inherited tool) Though now that I'm pushing to get going on building up my shop it's about time to get it going.
I seen a video where the guy used white vinegar, soaked it for a day, then took what looked like a wire brush to it and the rust all came right off. Seems like the vinegar would be less likely to leave anything nasty that would prevent the wax from sticking after rust removal, though I'm not sure.

This post was the first time I've seen razorblades referenced. Though I've seen plenty of references to wd-40 and scotchbrite. My main concern with using the pentrating oil, is that the wax won't stick to the surface. may be a non issue.


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## PBWilson1970 (Jan 23, 2020)

Using WD-40 while fixing the surface won't have an effect on the wax you might add afterward if you clean it off with mineral spirits or another solvent.


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## ohtimberwolf (Dec 17, 2011)

If you go the electrolysis route and are not familiar with it please be sure to do some research on how to do it.
You-tube is one place to check. I never used it except in my barn, in an open area, *not *where I was going to be working.
Be familiar with the concerns about the gas it produces. It is a great way to dissolve rust and easy to do. But be informed on the method. Just sayin… larry


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## Ocelot (Mar 6, 2011)

I love evapo-rust, but it's about $25/gallon, so 4 gallons is $100. I would try the electrolysis or citric acid.

I tried citric acid on a pair of scissors I was fixin to throw away and it did a great job. I was surprised. I passed cheminstry for 3 years, but I didn't learn much. I would not expect an acid to remove rust, but it does.

-Paul


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## Renegade1LI (Jan 21, 2020)

I have restored & polished lots of cast iron with great results, remember this is wood working equipment. I use a 3×21 belt sander starting with 150 up to 2500, than 3000 with an orbital followed by compound. I check the decks with a starrett straight edge & .002 feeler gauge, once done I give it a couple clear coats of urethane & good to go. I don't use my machines every day so the clear works great for me & just touch up as needed.


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## david2011 (Apr 1, 2008)

If you want a chemical method of rust removal I highly recommend Lime-Away. After trying several chemicals including Kleen-Strip Metal and Concrete Prep, PB Blaster and Scotchbrite, ROS and Boeing Rust Free, Lime-Away was both effective and easy to use. Rust Free does a good job but it is a LOT of work to get an even appearance over a large area like a table saw. I would not use Rust Free on something as big as a table saw again but will still use it for smaller tools.

I cleaned some minor staining and rust spots on my newest table saw with Rust Free. It looked really good for a saw almost 20 years old when I got it but I wanted it to be as mice as possible. After that it got Boeshield T-9 to help keep it free of rust followed by Johnson's Paste Wax. It's very slick and a delight to use.
https://www.lumberjocks.com/topics/311909#reply-5338479


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## Sketchman1981 (Jan 6, 2017)

I just finished removing the rust on mine. Tool 3-4 hours because I did most of it by hand. Used penetrating oil, razorblade scraper and scotchbrite. Heading to get paste wax soon


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## kelvancra (May 4, 2010)

If you use and orbital or other sander, you can also add mineral oil to work as a lube so the paper doesn't load with metal.

I used some of my worn out granite polishing pads and oil with my variable speed angle grinder and was able to get a mirror finish. It was beautiful, until I applied Corrosion-X, which, regularly applied, will make the surface almost bullet proof with regard to moisture.


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