I work wood in my San Francisco garage, where the fog rolls in every few days to keep me cool. It’s great weather, but my table saw and bandsaw top probably don’t like it much. Now and again they get a little spotty (I think from rust) on top, and I wonder what I can do to keep the tops shiny and looking new. I’m afraid to steel wool the spots off, as I might unflatten the tops in the process.
Has anyone else come across a similar problem and found a good solution?
Thx,
Rob
Replies
Rob,
I live in Fremont and do not have the fog (therefore moisture) problem you have, however, the humidity extremes in Fremont can still can cause surface rust if the bare metal is not treated. This must be very a very difficult problem to deal with on the East coast.
There was a recent post with many opinions on this subject.
To remove minor rust spots, I recommend using a lubricant such as WD-40 with a Scotchbrite pad and a random orbital sander. Take care to only lightly remove the rust. Then remove the oil with a solvent such as paint thinner. After that, apply several coats of a good quality paste wax. I like Johnson's or Trewax hardwoof floor paste wax. I apply a coat, buff, apply another coat and repeat until I have a good coat of protection. On the final coat, I use my random orbital auto polisher to give it a good shine. This is easy on my PM 66, which came from the factory with a polished top.
I like to apply a coat at least every month or whenever I feel the integrity of the protective finish has been compromised, such as after using the saw a lot.
This has worked for me. There are products like TopCoat and other dry film products that I have not tried.
Mike
humidity extremes in Fremont
what humidity... it gets hot in the summer and cool in the winter, there is very little moisture in the air (humidity), expect when it rains and you can count on that not happening from May through October. For extreme humidity, try Houston.
It can get very hot in Fremont, hot and dry that is.
That is very true.... but if I do not treat my table saw top, it still gets rusty!!
That is why I said that folks on the East Coast, where they get very wide humidity swings, the problem must be much more difficult to deal with.
If I can't see my face in my PM 66 table top, I'm not a happy woodworker!
Mike
I guess that's why people buy dehumidifiers, it's probably a requirement in some areas. Imagine what the humidity does to finishes as you are applying them. Personally, I have no experience with it as I live across the bay from you on the Peninsula.
I think your rust issue has to do with the mirror like finish on the PM, I have a unisaw and don't have any problem at all with surface rust. However, I have seen a lot of PM tables that have very light rust, so I'm thinking it has to do with the surface qualities being an accelerator for oxidation. What do you think? Do you cover your machines when not in use?
By the way, are you getting a lot of smoke from the morgan hill fire drifting your way? It's been super hazy today, but thank god it's been cooling down a little.
Jeff,
I have been looking for covers to use. When I had a Shopsmith, I had covers for all the major pieces. I am looking for breathable covers that will help protect the cast iron on my PM66, jointer and planers. I'm going to drive up to Woodcraft in Dublin this weekend to see what they have.
Depending on which way the wind is blowing, we can smell the fire as well as see the haze here in Fremont. I work just a few miles south of south Fremont in North San Jose where it is a little worse. This orning, I could smell the smoke.
Mike
Hi Mike,
I live in Tracy, we smell smoke all the time. Lot of grass fires. About covers for your
Machines Amazon.com ( Tool Crib ) has a good selection.
Dick
I agree with MikeK50. I live in Las Vegas, but keep an evaporative cooler in my shop which add plenty of moisture. After I remove the rust I rub on Johnson's floor paste wax. The only thing that Mike didn't say is that it, not only helps with the rust, it keeps the surface almost friction-free. Your wood will slide better than ever. I use this method on any tool that has a metal base.
Len (Len's Custom Woodworking)
This might only be a little help, since I don't know where to get this anymore, but a friend who worked at an aviation outfit gave me a can of lubricant once that he said they used to treat aircraft parts that were not able to be painted. I think it was called ACR 40, but not sure. This stuff was amazing. Sprayed on, wiped off, seemed to act a little like a penetrating oil but no residue, I've put it on the table saw top, all of my firearms (and ten years in the duck slough without rust on the shotgun seems to be a good indicator) - you could look up Duncan Aviation on the web and see if they'd tell you what the stuff was. White can with light red - almost pink lettering.
If you have them, check out the instruction manuals on your tools. They might have suggestions for table top maintenance. My table saw manual suggests the Scotch Brite and WD-40 idea. From a Fine Woodworking issue a couple of years ago, I use 400-grit silicon carbide (wet/dry) sandpaper on a sanding block and a little mineral spirits. After wiping the surface dry, I spray on TopCote as per the manufacturer's instructions. Sometimes the spray pattern results inblotchiness that requires a fair amount of downward pressure on my part when buffing it out.
Use steel wool or 600 - 800 grit sandpaper (lubricate with a light machine oil) to get the top clean and then keep the cast iron tables waxed so you don't have to keep repeating the procedure.
When I worked in an unheated/cooled garage I waxed my tables almost everyday as part of general shop maintenance and cleanup at the end of the day. Use a high solvent wax and you won't get a build up.
With fog rolling in , I don't see how you can avoid frequent waxing short of installing climate control in the shop.
Wow! I go home for the night and am greeted with 8 replies! Thanks for all the great tips, guys. I'll try the Scotch brite and WD40 ided, and then Butcher's Paste Wax every week or so. Sounds like a good idea...
Rob
My garage shop is a stone's throw from the Pacific. Needless to say, I was having problems with the top of my 1938 Unisaw rusting no matter how much paste wax I put on it. Then I bought a clear shower curtain (about $3) and cover the saw with it when ever it's not in use. Rust problems are a thing of the past.
Since space is limited in my shop I often use the table saw surface for glue ups. With the shower curtain in place I don't have to worry about drips or spills.
Brandon Ford, Lincoln City, OR.
Brandon,
I've always heard that you need a breathable cover so that moisture does not get trapped under a plain plastic cover. I guess you have proven that theory wrong.
How long have you been using a shower curtain on your table saw? It is certainly a lot cheaper than the "breathable" covers that are sold for this purpose.
Mike
I've used the shower curtain for more than a year with no problems. My reasoning is that since rust is oxidation, if you keep the oxygen away you keep the rust away. I do make sure that the table is clean before I put the cover on and I only work with dry wood.
Brandon
When I got my saw (second hand) it was rrruuuuusssstty I cleaned it up oiling the surface and sanding with 200 grit followed 400 grit emery cloth. I then flattened the top using oil and a dmt coarse diamond sharpening stone. Followed by 3 coats of top cote,this worked great. Now when I forget to reapply the top cote often enough ,about every 4 weeks a quick touch up with the stone and oil and top cote and back in business.
The diamond stone also is used to flatten my other sharpening stones.
What about sweat. When I use my table saw and jointer a lot of the times I'm sweating . A couple of drops seem to create instant rust. All of the surfaces have been waxed but if I don't wipe the sweat off right away I get rust spots. Is Topcoat better than wax?
Archy,
That has happened to me too! The salt in your sweat is the worst kind of moisture. I remove it immediatly. I often clean the spot with WD-40 and rewax the area.
I find that rewaxing often is the best way.
I have not heard enough good reports on Topcoat, or any other similar product to convince me to try them. I'd like to, however, beicase it is a lot of work to wax and polish. Somethimes it makes me sweat on my newly polished saw top!
Mike
I then flattened the top using oil and a dmt coarse diamond sharpening stone.
N
Norm -
When you say "flatten" do you mean just take out the sanding marks? How do you truely flatten the entire surface of something as large as a saw table with something the size of a sharpening stone?
Just curious. My saw table has an 0.008 sag on one corner. I was considering taking it to a machine shop with a surface grinder and having it flattened. The thought of removing the top of a 10" Unisaw, then reinstalling and tuning it doesn't appeal to me a great deal.
Dennis in Bellevue WA
[email protected]
Dennis:
Your table top with a .006" sag on one corner is in good shape. These tops must be jigged up on the surface grinder to keep the top surface parallel to the table movement. Not an easy thing to do considering the ribs on the under side.A freshly ground top will likely have that much error.
On my saw,I can`t think of any operation that would be compromised by such a small deviation.
FWIW ¬¬¬¬¬¬¬¬¬¬¬¬PAT¬¬¬¬¬¬¬¬¬¬¬¬¬
Dennis
I just worked it as relatively flat as I could working the stone left/right,front/back and circular, to truly flatten top would require machine shop milling unneeded and to expensive for me
Norm
Rob:
Now and again,I use paste wax on my C.I.table top.
I don`t believe that I would ever live long enough
to "unflatten" the top with steel wool.
¬¬¬¬¬¬¬¬¬¬¬¬PAT¬¬¬¬¬¬¬¬¬¬¬
This forum post is now archived. Commenting has been disabled