Are the effects of rust on machines over exaggerated?

I know that it's obviously not a good thing to have rust on your machines, and I do my best to keep mine from rusting. But when you bring up keeping your machines in a barn shop or something, people act like you are putting machines to their death. The humidity will probably create surface rust on the iron surfaces, but with routine maintenance, that should be kept to a minimum. And I think they're less common now, but I think barn shops are fairly common. Even if the machine surface does develop heavy rust, the only major issue I would see is losing the ability to smoothly pass through material.

I'm no expert, I may sound stupid, but I'm wondering if barn shops or any non insulated shops are really as bad for your machines as some say.

I haven't found it to be too bad. It takes neglect to actually pit the iron. Other than that, flash rust creates a rough surface that needs to be cleaned off and that's about it. I had a shop in the coastal mountains for awhile and my table saw and jointer were semi-exposed. I used breathable machine covers and tarps and things like that. When it rained the machines would still get a bit of rust but I'd just clean it off and get back to work.

In my experience, moisture/condensation is much more of an issue for electrics than it is for cast iron or steel. At least from a functional persective.

Erik Loza
Minimax USA

To put it into perspective.. Take a look at and of the Old Tools forums where people are pulling 80 year old cast iron monsters out of the back field with weeds growing around them and they seem to be able to restore the machines back to perfect health. Keeping a too in a barn is nothing compared to leaving it outside in a field for 40+ years.

I am going disagree here. Near the ocean rust develops very quickly and seriously damages the metal.

Attachment 287543

This piece of iron was wet and left inside our house for the last ten months as an experiment. As you can see the metal is well beyond surface rust. I am not saying that being left in a garage or barn invariably leads to this. But while it starts slowly rust can very quickly damage the iron if left unchecked.

I am constantly vigilant against the elements and rust.

It takes a very aggressive environment to damage machine surfaces to the point where you'd notice diminished function. My jointer is fairly pitted, but the surface is still true since the pits never got together to form canyons :D Many find it horribly ugly, those deep pits. But they don't affect the function at all.

I've never had to deal with a coastal environment, that humid salt air can be very aggressive. But anywhere else, I tend to think people's reaction to a little rust is based on aesthetics more than substance.

I've noticed there is no problem with the painted surfaces of cast iron rusting. Maybe we just need to clear coat the bare areas. I hate rust spots on my machines. Had a hand print on the table of my unisaw, put my hand down flat on it on a hot day.

I've bought a few machines with surface rust on tables. A little scotch brite, some oil and wax, not a problem. Some of the surfaces are even pitted....awful I know, I hate to push rough hard wood over surfaces that aren't perfectly shiny and smooth. :rolleyes: I remember a recent post where a guy wanted to sand smooth the Blanchard ground table on a minimax because it wasn't shiny and smooth.....guessing he would not like my shop. I doubt I have the will to take back a field wreck from rusty scupper to working artifact, but the kind of rust you get in a barn or basement shop is to me of little consequence, mice do more damage.

I've brought back rusty machines, and I have an uninsulated (for the time being) garage shop where tools do get a bit rusty at times when the humidity is high. The only problem I have with it is the time it takes to get rid of the rust, which takes me away from working wood.

I dare something to rust in my shop! (clutches bottle of Evapo-rust in a threatening manner)

Yes, the effects are exaggerated. I used to be really worried about minor rust on my machines then I met a guy who had all of his tops get covered in solid brown rust and he removed it with a wire brush on an angle grinder followed by either oil or wax, not sure. I viewed and used some of the machines a month or two later and would have never known the difference in sight or feel vs my machines that I take impeccable care of.

I'm not going to stop trying to keep rust off my machines, but I'm not going to complain as much either if a friend sets a beer on them. I view it as an annoyance to correct now, not as a permanent effect on the machine.

I have purchased and restored many old woodworking tools. Many woodworkers avoid the tools with rust at auctions but truth be told, it's very easy to remove most rust on tools not found in saltwater areas. Very rarely will one find pitting when one sees surface rust.

Yea that salt water air is unforgiving, but thankfully I don't live anywhere near that kind of air. I remember when I first set out to buy my first truck, I drove out near the shore to look at one I thought I was getting a great deal on. It was a newer truck with only 50,000 miles and the guy wanted a bargain for it. When I got there I realized why, because the whole underbody was rusted up pretty bad

Cosmetic surface rust is one thing but deeper blade and inner condensate bearing rust is another. I live on the Ches Bay and have an unheated shop and have experienced both 'salt air acid' and saltwater flood damage. This is a rust question, and in my opinion condensate rust is a pain in the butt but not a tool/machine killer and is a controllable malady. I fall on the side that rust is overrated as a shop virus and though rust and discoloration are obvious nuisances, they are not lethal to shop tools or truck engines or flag poles or digital pc boards or anything else. Cosmetic rust sometimes calls extra attention to maintenance and upkeep and with a table saw in mind, I bought a tub of paste wax last week.