Rust removal and prevention

[neilc]

I realised a dream back in October when I imported a unisaw from the States (model 36-831). As it is my first cast iron tool I didn't realise how high maintenance the table is. My workshop is quite damp as its one of them metal sheds with no insulation.
Anyway I'm fighting a losing battle with the rust. I've just given it a good cleaning with a scouring pad and WD40. The top has quite a few flecks and stains at this stage. I plan on leaving the top soaking in WD40 tonight and giving it another going over tomorrow.
I don't mind the stains so much if i killed the rust. Insulating the shed isn't really an option at the moment as I'm hoping to move in the next year. Any ideas on what to do to prevent more rust and is it a good idea to leave it soaking in WD40 till tomorrow evening.
Cheers,
neilc

 

[ikd]

Rub clear wood wax on the iron table, it should inhibit the rust and also aid in feeding the wood through the saw (less friction).

I also have a fairly damp garage. The only thing I have with a cast table is a Basato 3 band saw. I have had this over two years now without a mark. Also covering the machine with an old bed sheet or similar will help.

 

[johnjin]

Hi Neil

I find this stuff very good.

http://www.axminster.co.uk/name/liberon ... -22593.htm

I've been using it for a couple of years now and find that rust is a thing of the past. And the difference when you are pushing a piece of wood across the table is remarkable.

All the best

John

 

[Noel]

I'm not sure soaking the table in WD40 will do much good. The use of a scouring pad will do little good either. WD40 is often mentioned when cleaning TS tops but it's only function is as a lubricant and somewhere to suspend any waste metal/rust during the cleaning process.
Ideally you need a ROS (or even a palm sander) with a Webrax (green is suitable) pad affixed to the velcro base. If no Velcro double sided tape works well. Use WD40 or thinned light machine (3 in 1 type). First thing to do is to clean the top with white spirit or thinners etc to remove any grease or glue etc. Once dry apply the WD40 / oil quite thickly and let go with the sander and webrax. Often this process is sufficient to clean up the surface but if the rust is quite bad a further stint using 320 grit paper on the sander may be needed. It's best to clean the table with thinners to get get rid of the WD40 and rubbish removed during the first stage. Once dry re-apply the WD40/oil and sand the table with the 320 grit. Clean again, let dry and then apply 2 or 3 coats of paste wax (Briwax etc) and buff out. Apply the wax every fortnight to the top as well as the front rail and the cam lock.

Noel

 

[ProShop]

I use wonder wheels to remove rust, it works a treat without any effort. And it removes the rust without affecting the good metal surface.
If the rust is really bad or has been there a long time just agitate it with wire wool, and you then need to neutralize the wonder wheels afterwards. And then use any of the proprietary treatments to help prevent the rust returning. I use the same as you, WD40 or similar, contra to popular believe WD40 contains no silicone . For longer term protection if your not using the machine much, is to use a silicone free oil, I find this very effective. I tried the Libron, but IMHO it's not as good as the oil.

Hope this helps

 

[neilc]

Thanks for all the really quick advice guys.
Noel, what grit is the Webrax green, sounds promising. I think i would be afraid to go at it with 320 grit paper, as there is a possibility of creating hollows on the table.
FelderMan, what actually is wonder wheels I've never heard of this product.
Will the rust keep coming back if I don't get the staining off the surface. I also find that when I use wax I get track marks from my sled and fine dust is attracted to the surface which maybe is adding to the problem. Would Liberon Lubricating Wax be better in this regard.
Thanks again,
neilc

 

[Unlucky Alf]

what actually is wonder wheels I've never heard of this product.

Assuming that Felderman is referring to the same product Wonder Wheels is an acidic alloy wheel cleaner which is available from Halfords and other such places. It's great for laquered alloys but I've never tried it in the workshop. Perhaps I'll give it a try as well.

Will the rust keep coming back if I don't get the staining off the surface.

In my experience, yes it will. It's like cancer, get rid of all of it or you'll be fighting it forever.

I don't think you need to worry too much about creating hollows in a cast iron top with 320 grit. I'm sure it's possible with enough dedicated effort but I suspect that the chances of doing it accidentally with an ROS are pretty slim. The rust will do it however so get rid of it as quickly as possible.


Good luck,

Simon

 

[Noel]

Webrax is just an industrial version of the scouring pad you've already used. You'll not create any hollows with 320 grit paper. Bear in mind that when treating the table you should treat the whole table, not just the rust spots.
Sometime when you've a magnifying glass or an eye loupe handy have a look at the surface of the TS. You'll be amazed at how pronounced the grinding marks are that have been left by the factory. You can even feel them when dragging your finger nails over the table.
Here's a rather poor 10x picture of the factory grind on my TS:

Track marks are nothing to worry about. Use a heat gun or a hairdryer to harden the paste before buffing. Personally I find paste wax miles better than the Liberon stuff. Lastly don't worry about dust, after all there does tend to be a good bit of sawdust on a TS the odd time.....
Just DAG Webrax or have a look for it at Axminster.

Noel
PS not sure if Wonder Wheels would be a good idea. Are't you supposed to wash it off with water? Maybe neutralize it with vinegar. And if it only attacks the rust won't that leave pitting? IMHO I find the Webrax and sanding process leaves a superior finish.

 

[Philly]

NeilC
I read on an American forum that a chap made covers for his cast iron tools out of thick cotton towels. These kept the tops from rusting (combined with a good waxing). Might be worth a try
Hope this helps
Philly

 

[Scott]

I read on an American forum that a chap made covers for his cast iron tools out of thick cotton towels. These kept the tops from rusting (combined with a good waxing). Might be worth a try

Were the towels in contact with the CI? If so I reckon the cotton might be a harbour for dampness in a really damp atmosphere(?) - a bit like sawdust and shavings left on your planes attracting moisture and causing rust.

Thinking out loud here....

 

[SammyQ]

At the risk of making a complete fool of myself, don't I recall a post saying that White Spirits (and by definition then, WD40) contains a small amount of water? Isn't this the reason that in FULL de-watering techniques White Spirit usage is followed up by a more truely organic, ie water free, solvent like cyclohexane?
IF I'm right, then de-rusting as directed above would be slightly negated and should be completed by using some proprietry form of phosphoric acid (Tenolite etc).
For the record, I buy WD40 in gallon containers and reckon it's great, but not perhaps for full de-rusting.

 

[beech1948]

neilc,
i think this has been covered before so maybe a search would yield some results.

My own approach has been:
1) Buy and use a dehumidifier. I run mine all day but turn it off at night but if you have persistent damp then let it run all the time. Get one which allows you to run a tube out of the building to drain
2) I think you mentioned a steel structure...so buy a can of instant foam and close up all of thew gaps you can see along the roof line, the sides, the floor etc etc...its fairly cheap to do but a bit smelly
3) Find something else rather than WD40 as its main calim to fame isn't to resist rust but to evaporate and leave a cleanish slightly oiled surface. Try using the green webrax to clean off ( with WD40) then clean all of it off and find another product. Try using whatever the Navy uses.
4) Provide a cover, often an old blanket to cover the machine, to create a micro climate, dry because of the dehumidifier and oily because of whatever you have used.
5) Use machinery/tools often to prevent rust build up
6) keep smilling

 

[Philly]

Scott
Yeah, the blankets were in contact with the CI-he said it worked great (and the chap lived in a very humid part of the States).
Havent tried it myself (thank the Lord for a dry workshop )
Cheers
Philly

 

[Chris Knight]

Cast iron is pretty porous ( an effect of the graphite inclusions) and will absorb oils to a degree. A thorough waxing with webrax and a paste wax will leave wax in the surface of the iron which will do much to protect it against rust.

Be prepared for a dirty job the first time you do this - it can also take a long time. When I first got it I spent an hour or more on my tablesaw top with white spirits and webrax until I was not getting more black gunk out of it (this is the "loose" graphite). I then waxed it and it is now slippery and clean to the touch and hasn't needed redoing.

 

[ProShop]

FelderMan, what actually is wonder wheels I've never heard of this product.

neilc

It's an alloy wheel cleaner for cars etc, their are similar cheaper variants on the market that work just as well.

 

[neilc]

Well lads can't thank everyone enough for all the advice. I just spent the last 2 hours ROSing the top with webrax. A bit of a messy job, a lot of black gunk came off, but I can't believe it, every stain is gone . Its like new again which I didn't think was possible.
I've cleaned the top a few times with white sprit so all I've left to do now is wax it. Should I buff between coats or just on the last coat. Also when re-applying every couple of weeks do you remove old wax and clean it down again with white sprit.
I'm also going to build a light plywood frame with a towel fixed to the inside to sit on the table when not in use. I think I'd be more likely to use the towel this way rather than it falling off every time I walk past the table saw.
Thanks again,
neilc

 

[ByronBlack]

I've been reading this thread with interest, as i've noticed that i'm getting a very thin and patchy film of light rust on my Planer Jointer tables - i'm clear with how to remove it, but i've seen 'paste wax' recommended a lot, can someone recommend a brand and where to buy this?

 

[ByronBlack]

Another small tip that I was told - attach some rare earth magnets to a towel or synthetic chamis, then when you put it over the machine, the magnets will hold it in place.

One other small thing for rust prevention: would those little silica bags that come with new shoes be a good idea for tools in drawers/cabinets to draw away moisture?

 

[les chicken]

When I was extending my garage :wink: I wound the blade right down on the TS and covered it with a piece of 18mm MDF.

The condensation was running down the walls from the new floor and render drying out.

The machines I covered with sheets, bandsaw and spindle sander their surfaces where covered with surface rust. The TS was spotless, I have kept the MDF to use as a cover and also use it for an assembly table, nice flat surface.

Les

 

[Noel]

Neil, wax and buff each coat. Two or three coats should do. You want to build up a good thick layer. Every 2 weeks re-apply and see how things go. Maybe strip back every other month or so.
Not sure the towel as a tent thing would work. The towel may absorb the moisture and in turn "soak" the air in the tent. Personally the only thing I'd cover a TS with is a sheet of board where damp air cannot enter or one of the HTC machine covers. Might be worth a try just leaving it, ensuring that there is a good layer of wax (such as Briwax).
Let us know how you get on.

Noel