Ideas for Removing a Rusty Table Saw Arbor Nut
Shawn KirschDescription
There can be real value in getting your tools used instead of new. However, used tools can have their “warts.” Every once in a while our readers, and the director of our woodworking videos, run into problems working with these older tools and come to us with their questions. In this case, the table saw arbor nut on Sam’s older Craftsman table saw was completely frozen in place. The original wrenches distorted badly as he torqued on the nut, refusing to budge it at all. He needed a higher horsepower solution, and we figured that out for him. Have a look at the solution that finally had an impact on the problem with Sam’s table saw arbor nut.
Rust is common
One of the most common problems with older tools is rust. A cast iron surface doesn’t have to be rained on to develop rust. Ambient humidity, or a misplaced can of soda, can be enough to get rust forming. Whether you’re using older tools, or want to protect the new tools in your shop, knowing how to clean rust off of them is key.
Other common issues
Another problem with older table saws is wear and tear on the arbor itself. Think of the number of times an arbor nut is put on and off a table saw. Over time the arbor threads can become worn, preventing you from getting the arbor nut tight. Luckily there’s a pretty easy fix that will allow your table saw arbor to snug up again.
At Woodworkers Guild, we very commonly get questions from people who have bought older tools, they've run into some problems with them and they want some advice. And thankfully right here in house, our director, Sam, now you were given an old table saw, you didn't buy it, right? Correct, yup, yeah. So, give us first the backstory, what's the history of the saw, what's the deal? Okay, so the backstory is I've been directing Woodworkers Guild videos for three years now, and so I've taken an interest in it. And while taking an interest in it, my father-in-law is transitioning between houses at this point and so he has given me his tools on the conditions that I have to let him use them whenever he needs to. That seems like a good deal. Yup, so all this stuff has been out at his shop for quite a while, I don't think he's used it for a few years now, and so I'm trying to get it all to work. And right now the main project is a bookcase and I'm using the table saw but it's got the wrong blade on it and it's been rusted solid. And then, and you talked to your father-in-law about this and he thought that blade went on, it's like pre-World II or what? Yeah I believe the text was, "Yeah, I haven't changed that one in a while." Okay. Yep. So what type of saw, what manufacturer? It was a Sears Craftsman. And any idea of the vintage of the saw? I have no idea. I know that there's a manual somewhere. I just haven't dug through all the paperwork to try to find one. And then, so you knew enough to recognize the wrong blade was on there and the problem you ran into was? Trying to get the arbor nut off. And once we, you grab some wrenches out of my toolbox here and- Well, I first started with something that looked like this, this is what kind of came with the Craftsman, was something thin like this. And what was happening was it was actually too thin for the bolt and I was cutting into the bolts as I was trying to crank that arbor nut loose. So yeah, then I had asked you about it because the next thing I was gonna do is take a torch to it. Yeah, and I thought, so Sam asked about a torch and I'm guessing it's not a good idea because somewhere on the back of that arbor, there are bearings. Right. And I think if you got it hot enough to cut the, to get the nut to come loose, you'd probably have an adverse effect on the bearings. Right. All right, so at the end of the day, what was, I think this is a great problem 'cause other people with older machines could run into this. So it looks like the problem solver found us. Yeah, it was a combination, you had told me about the impact wrench and so that you had one that you could borrow me and I ran home on Tuesday to go try it out. 200-mile roundtrip to- Yeah, 200-mile- See if it would work. Yup, and it was actually, it was a combination of that and then an adjustable wrench to get a little bit more bite on the other bolt. So I had to use this guy, snaked an extension, poked my head through the wheel to turn the blade, and eventually I was able to crack that nut. And did you have to put, so the crescent wrench was on the inboard side of the arbor to lock that in? Right. So you weren't, my question was gonna be, you didn't have to jam wood against the teeth of the blade to lock that up? No, so the way that it turned, there was a piece in the machine that it actually locked up against so that I could still turn it. And the deal with an impact driver, if you can get one, an impact wrench, is that it pulses out, just like impact driver you drive screws with, you get this So like working on a car, even if a wheel has been jacked up but you're using an impact driver, impact wrench to take the lug nuts off, it'll do it without the wheel spinning and getting away from you like it would with a lug wrench because you're spinning it so fast. You're spinning it faster than the whole device can spin. So that's kind of why I thought, similarly on the table saw blade, that might crack it loose. So at the end of the day, the arbor nut, I'm guessing, is it salvageable? You're gonna be able to use it again or did it get so torn up it's shot? No, it's salvageable, yup. Oh, I'm amazed. Yup, yup, I mean, I just had to clear the rust off of it, but it's still, yeah, it still works. And then did the blade come loose easily enough off the arbor once- Yup, yup, and even the washers were still usable. It was pretty surprising once I got it off. So the biggest struggle out of this, I mean, one was just the knuckle-busting initially, but then two, snaking this up in there 'cause there's not a lot of room under it. Yeah, that was a beast because, yeah, I could not get right without actually having to like peek through the hole in the actual tool. Highly subjective, this is a pretty big impact wrench. This is a, this exerts 450 foot-pounds. Do you think that if you had tried a smaller, like an impact driver, do you have any guesstimate, might that have cracked it loose or you think it took like every bit of power this thing had to make that? I'm not exactly sure 'cause I mean, it did the job so I don't know if smaller would have worked or not. 'Cause it didn't occur to me, I've got some impact drivers in here and part of the problem we would have run into is that a lot of those are a very small hex drive. So how we woulda stepped that up, you had to use a pretty good-sized socket on there, right? Yeah- To get a fit. If we would've gone with a smaller one, I would have used the exact same technique because there was no way anything could have fit in there after you got the socket on. Yeah, so getting a small impact driver stepped up to that biggest socket, I don't think we could have done it. Yeah. Well, good. So I'm glad it worked and there's some potential advice for you if you ever run into a similar problem, to make sure you can get your arbor but loose. Any other old tool advice for the folks at home? I'm sure there's more to come. I've got a few other tools I'm working on. Some more tool rejuvenation tips coming from Sam as we come across it.
was up against a similar situation removing the pulley nut on a Craftsman lawn tractor blade mandrill (Husqvarna, actually). There, access was not an issue. I kept the pulley from rotating with a Vice Grip applied to it. I tried 2 heavy, 120V, impact drivers and even torching it with no success. I finally bought a really huge impact driver from Harbor Freight and it broke the nut off with a piece of the shaft still in it! A new mandrill assembly (which was much cheaper than the impact driver) was the ultimate solution. My table saw is also a Craftsman that I bought from Sears 40+ years ago. Rust on it has never been an issue since I use it a lot. If I had run into this problem, I would have approached it somewhat differently. The arbor nut wrench that comes with the saw will never be able to loosen a rusted-on nut. It is too thin, insubstantial and its inside edges will get rounded off. But first, I would try applying something like Liquid Wrench (which has worked for me in these situations better than WD40) and let it soak in overnight. Getting access to the nut would probably require disassembling the saw from the table or at least turning it over on its side or even up side down. An impact driver would work the best, if you can get one that is powerful enough and will fit inside the cabinet work space. You need to be able to stop the blade from moving and you can probably do that with a Vice Grip applied to the blade. You also need the correct sockets. The ones shown are NOT designed for impact drivers. If the nut won't move, the chromed socket will likely crack. Impact sockets are usually black and heavy. They should be at least 1/2" drive. Using socket adapters will reduce the available torque, plus they can easily break. An impact driver that is more than you need is not the problem since the nut will come off more easily than when using an under-powered driver. It should go without saying that you should make sure the driver is actually set to work in the reverse direction (who of us has never made that mistake?)! As for torching it, some of the issues have already been mentioned. In addition to the fire and burn risks, you can actually inadvertently weld it on even more if you get the nut red hot. It would be the last thing that I would do before giving up. Basically, there are only 3 possible outcomes: the nut comes off, the nut doesn't come off and the nut breaks off destroying the arbor. For anything other than the first outcome, the next steps are to remove the motor, pulleys and safety switch, and then donate the rest to your local recycling center.
A squirt of EvapoRust would have made the task a lot easier.
Applying AeroKroil penetrating lubricant will generally allow easy removal of rusted and stuck nuts and bolts using only a wrench.
If it still hadn't worked, and only as a last resort, you could cut the nut off. I have done this on several other applications where the nut was not salvageable. I prefer my Dremel rotary tool with a fiber cutting wheel. Be sure to wear safety goggles as the wheel can sometimes fly apart (especially if it gets twisted). Cut down parallel to the shaft almost to the threads. At that point you should be able to break the rest of the nut with a wrench. The nut will expand and you can unscrew it. Be sure to clean the threads off with a steel brush before you put on the new nut.
Table saw arbors are usually buried beneath the top, making it impossible to get an impact driver onto it. How did you seat the driver onto the arbor nut?
You are looking for a accident to happen by not using an impact socket. Chrome sockets shatter very easy when used with a impact wrench.
Wouldn't an air impact ratchet or possibly a long Gear Wrench be better? I also noticed the sockets used were not impact grade that tend to be 6 point and designed for higher torque, those used may have life warranty but use on an impact is an exception to same.
To loosen stuck rusted nuts and bolts on woodworking equipment TopSaver is the Product for you. It Penetrates to the bottom of the surface pores on a microscopic level faster and better than most petroleum penetration oils. TOPSAVER will also break the bond of the rust on contact so a little vibration from a impact driver or tapping on the nut with a wrench will help free the bond. Applying Topsaver to the nut and arbor threads will also help this from happening again. Topsaver is available at www.xspeedlube.com and amazon.com
When taking off the arbor nut you had tried two wrenches, I believe these wrenches are for a Craftsman radial arm saw if this is one of the tools you also received.
An interesting video. I have sometimes found that a sharp tap on a well-fitting wrench in the tightening direction before trying to loosen a nut may work. It seems to crack the rust-bond. I agree it seems to go against all reason... On the matter of slipping belts, I have a Kity woodworker and have found that turning the fabric belt inside out works. It seems to have a bias one way, possibly something to do with the fabric weave. (You have to move the belt each time you set up a different tool: it's French...)