A word on magnetic tool holders

[Jeff Grantham]

I thought I was a real genius when I was setting up my turning space and purchased a few of those magnetic tool holders to hold all my turning tools up on the peg board. Never even considered the fact that my tools could become magnetized and stick on the rest as a result. Doh! I didn't notice at first... don't know if it's gotten worse, or if I've just become more sensitive, but I started realizing that it was practically impossible to make a nice long cut without hesitation along the way, due to the magnetism. Really frustrating.

Anyway, I did alot of searching and found a suggestion that if you hold your tool pointed north and run a super strong magnet up and down the shaft of the tool, with the magnet facing east-west, that it would remove the magnetism... sounded pretty crazy to me but I decided to try it... and by golly it actually worked! No more attraction to the rest! The tools are now all laying on the workbench until I find a new home for them.

Just thought I'd share the experience as a word of warning for anyone thinking about using those, and/or a possible solution if anyone ever finds themselves with the same problem :)

[Bob Bergstrom]

Been using magnets for 15 years. The mind is an amazing thing. I don't notice the difference anymore and pushing or pulling cuts all feel the same wether a new or old tool. It is kind of like people on Facebook want you to read things backwards or up side down. The mind just adjust to it all.

[Michelle Rich]

mine are on magnet racks too...no problem in over 1/4 century

[Jeff Grantham]

Perhaps newer holders are stronger? All I can say it that it was strong enough that I literally had to tug lightly to lift it off... particularly on my 5/8 bowl gouge. And so it caused resistance whenever I was making cuts that required the tool to slide along the rest, which was annoying enough that I won't be going back to using magnets anymore.

[Dan Hintz]

Anyway, I did alot of searching and found a suggestion that if you hold your tool pointed north and run a super strong magnet up and down the shaft of the tool, with the magnet facing east-west, that it would remove the magnetism... sounded pretty crazy to me but I decided to try it... and by golly it actually worked

The compass direction in which you hold the tool/magnet makes no difference, only the direction of the magnet's poles with respect to the axis of movement. You can buy demagnetizers that are essentially pre-packaged versions of what you did, just run the tool in/out of the opening a handful of times and it randomizes the magnetic field in the tool.

[John Keeton]

Jeff, just to comfort you, I had a similar experience early on and relegated the magnetic holder to holding my Allen wrenches, chuck key, knockout bar, etc.

[Jeff Grantham]

The compass direction in which you hold the tool/magnet makes no difference, only the direction of the magnet's poles with respect to the axis of movement. You can buy demagnetizers that are essentially pre-packaged versions of what you did, just run the tool in/out of the opening a handful of times and it randomizes the magnetic field in the tool.

That makes sense - I thought it sounded a little cockamamey (sp?), but was willing to try anything. I'd read that the store-bought ones weren't strong enough for anything other than small screws, drivers, etc.... but thanks for the explanation and the tip!


Jeff, just to comfort you, I had a similar experience early on and relegated the magnetic holder to holding my Allen wrenches, chuck key, knockout bar, etc.

Thanks John! I appreciate hearing that I'm not the only one (and that I'm not just crazy... [which might be true] but this was real!)

[Dan Hintz]

That makes sense - I thought it sounded a little cockamamey (sp?), but was willing to try anything. I'd read that the store-bought ones weren't strong enough for anything other than small screws, drivers, etc.... but thanks for the explanation and the tip!

You do need a strong magnet (either to permanently magnetize the tool, or to demagnetize it later). The strip I had in our old kitchen (never reinstalled in the new one) had pretty strong magnets... took a good tug to get the knives off of it.

They also sell electric demagnetizers... no need to run the tool back and forth, just stick the tool inside and press a button.

[Chris Colman]

I have been using a magnetic strip to hold tools many years. The only thing I have noticed is the annoying collection of metal filings on the tip if I let it get around them.
I have never noticed any attraction to the tool rest.
Might be nice to demagnetize them, though. I will have to try that.

[Paul Lawrence]

A bit of an old thread, but I did want to respond.

I've been using this "magnetizer" / "demagnetizer" for many years in one version or another. It's the main guts from an old cheap fan motor with the rotor part removed and an appropriate cord attached (safety first!) This particular one has an overheat feature in the line, but you should only be using it intermittently anyway. I usually have this mounted to a part of my bench or a shelf with a push button switch.

Plug it in and place your screwdriver / tool inside the hole or adjacent and withdraw. The screwdriver will be demagnetized.

If you want to magnetize a screwdriver tip, place it inside the hole while power is applied. Then turn the power off. The randomness of turning the power off will leave the part magnetized. I've had to do it twice once that I can remember.

Ain't magnetism fun? :D

335928

[hu lowery]

Pretty low heat will demagnetize a tool too.

Didn't notice this thread or had forgotten about it. Reminded me of something that happened back in the sixties. My dad sold Forney welders. Back then these things had huge copper coils, pretty much all they were. There might have been fifty pounds of copper in these machines at one time. In an unusual move the owner of the company quit making welders when he couldn't make the quality of machine he wanted to make at a price he thought they could be sold for. Anyway, magnetizing something with this huge copper coil and 240 volts made a very impressive magnet.

Dad showed a mechanic how to do this. Happened to pass by a few days later and he had magnetized almost every metal tool in his shop! End wrenches and everything was magnetized. Instead of magnetic racks he just slapped the tools against flat bar in his shop, reminds me, that demagnetizes things too, hammering on things that can be hit. You had to take the top cover off of the welder to do this and obviously he had been having too much fun! Came back by a few weeks later and things were back to normal. He had found that having his whole world snap together like dried out spaghetti wasn't really the best idea. sockets and such went to the nearest metal instead of where you were trying to get them to and all of his tools in a tray or bucket had been one big ball. It was funny seeing how excited he had been about magnetizing everything and then how opposite his reaction was once the cool factor went away in a hurry when he tried to work with the tools.

Hu

[John K Jordan]

I also found magnetized turning tools a problem - both with sticking to the tool rest and with dragging a long trail of annoying black steel dust when sharpening with a CBN wheel on the Tormek.

A possibly interesting thing - steel can be magnetized just by sitting in the same position in the earth's magnetic field. You can verify this with a compass with something like a refrigerator or dryer: the N-S needle will swing when moved from top to bottom. I found even steel cans on the shelf eventually got magnetized. Even my lathe tools that never touch a magnet get magnetized, I think it is because they are held generally in the same orientation while turning and the vibration from the turning accelerates the magnetism.

I use a bulk tape demagnetizer I bought many decades ago, probably in the '70s. I don't know if they still make these but I do see special tool demagnetizers on Amazon.

Concerning magnets at the lathe, here is something I do which is a big help. Many people keep small allen wrenches, dental picks, screwdrivers, etc at hand with magnets. For things that won't stick to magnets like pencils and markers, I wrap a few turns of soft iron wire around the ends. This lets me stick them where handy so they are always in the same place. I do this at the lathes, bandsaw, SCMS, etc., anywhere I often use pencils. I use screws to mount the magnets with countersunk holes to places where magnets won't stick.

JKJ

[Dan Hintz]

The Earth's magnetic field is so weak it would have negligible effect on a piece of metal. To convince yourself, use a cheap refrigerator magnet (like the kind they use for pizza store advertisements) and try to magnetize a tool... nothing appreciable, right? That magnet is a couple orders of magnitude greater in strength than the Earth's field.

[Paul Lawrence]

A possibly interesting thing - steel can be magnetized just by sitting in the same position in the earth's magnetic field.

If you have a tool made from a "steel" that can be magnetized by sitting in the earth's magnetic field, you wouldn't be able to cut with it for very long. That's why your standard "horseshoe" magnet is made from "soft" material.

Your tools may be positioned near a motor on your lathe which can create a transient magnetic field when you turn it off and on. Mount your tools in a different orientation to correct this effect.

[Dennis Peacock]

Now....if I could only magnetize all the stuff I need to keep in my brain? That would be ever so awesome!!! :D

[Quinn McCarthy]

I bought a double magnetis strip to hold my turning tools and it was so bad it wouldn.t hold my smallest turning tools. I was thinkng about 112lb magnets I found on sale online. That should hold my biggest tools.

Quinn

[Jamie Straw]

A couple of my early, cheap tools have become lightly magnetized, for seemingly no reason -- a 1" roughing gouge mostly notably. I actually like it, 'cause when I lay the credit-card diamond hone on it, it lays perfectly flat on the bevel, with just a light magnetic tug. Have no idea how it got magnetized, I never have held it with a magnet to anything.

IMHO, a good use of magnets for tool holding would be to combine them with a slanted wood holder, just enough magnetic hold to keep them from getting jostled out when removing an adjacent tool. On my list of "to build" accessories.

[Jamie Straw]

Try Lee Valley -- their magnets and magnetic accessories are quite good.

[Kyle Iwamoto]

My Thompson V-gouge has gotten magnetized also, so I don't think cheap tool has anything to do with that random magnitization. That gouge has never seen a magnet. It has the most magnetism....

I use a HD magnetic bar on my mini lathe bench so the toys, er tools don't roll off. I did put a strip of duct tape on the magnet thinking it would help keep tools from direct contact with the magnet. Unsure if that has any effect.

[Paul Lawrence]

I did put a strip of duct tape on the magnet thinking it would help keep tools from direct contact with the magnet. Unsure if that has any effect.

The only effect that has is to reduce the "pull" of the magnet on the tool. Similar to the effect of a refer magnet trying to hold too many pages of notes to your refer door.

One way to keep stray (electrically induced) magnet fields from magnetizing your tools is to "encase" your tools in a soft iron pipe with an iron cap on one end. The pipe will contain the magnetic fields (along with the cap at one end. There will be some "leakage" of the field at the open end of the pipe, but it will be very small.

[John K Jordan]

If you have a tool made from a "steel" that can be magnetized by sitting in the earth's magnetic field, you wouldn't be able to cut with it for very long. That's why your standard "horseshoe" magnet is made from "soft" material.

Sorry, this makes no sense to me. I use Thompson Tools made from some of the best steel available for turning, 10v(A-11), very hard and can easily be magnetized.

The softer irons and steels do not make good magnets. That's the reason electromagnets have been made with soft iron so the core will not remain permanently magnetized when the field is switched off.

JKJ

[John K Jordan]

The Earth's magnetic field is so weak it would have negligible effect on a piece of metal. ...

Yes, I can understand why you might think that. On the surface it doesn't seem logical that the weak magnetic field can magnetize anything. However, this is true. Here is an answer to this very question from the U of Illinois Physics department: https://van.physics.illinois.edu/qa/listing.php?id=436

In fact, making a magnet this way is a common science experiment for kids. To convince yourself, try it!
http://classroom.synonym.com/magnetize-things-6377.html - striking method
http://m.wikihow.com/Magnetize-Steel - method three
(Just remember that some types of ferromagnetic materials cannot be magnetized by any method.)

Note that the steel will eventually become magnetized without striking, but this will take a long time (months or even years). The vibration causes this to happen immediately. The physics article describes magnetism of railroad rails due to vibration from the train wheels.

30 years ago we did a simple experiment: using the compass technique I mentioned, we checked a steel object and noted the magnetic field orientation in the object. The object was inverted and rechecked much later - the field had inverted!The vibration principle is why I wondered if lathe tool vibration could be responsible for magnetized tools.

Note the magnetism I observed at the CBN wheel was very weak but still enough to hold fine steel dust. I did not experiment - perhaps the Tormek itself or the action of the CBN wheel itself contributed.

JKJ

PS: I do not claim to be an expert in the physics of magnetism, just a curious amateur. However, for many years I worked in a laboratory with experts - we had many interesting discussions, projects, and experiments. For good fun, try magnetically levitating a PM rotor in an extreme vacuum and spinning it faster and faster with magnetic fields until it explodes! Actually, don't try this at home...

[Paul Lawrence]

Hey, everything is relative.

Sorry I dumped on your "best steel" pride. Didn't mean too. :D


Sorry, this makes no sense to me. I use Thompson Tools made from some of the best steel available for turning, 10v(A-11), very hard and can easily be magnetized.

The softer irons and steels do not make good magnets. That's the reason electromagnets have been made with soft iron so the core will not remain permanently magnetized when the field is switched off.

JKJ

[John K Jordan]

Hey, everything is relative.

Sorry I dumped on your "best steel" pride. Didn't mean too. :D

This has nothing to do with pride in tool ownership. This is about physics and material properties.

Perhaps I misunderstood your point. I thought you wrote that a tool easily magnetized would not hold an edge very long while turning. That turns out not to be the case. The tool steels that hold their edge longest such as the 10V can indeed be easily magnetized. I have seen it with my own eyes. I have demagnetized them many times.

Of course the reason they became magnetized is a matter of conjecture until tested further.

JKJ

[Paul Lawrence]

Sorry, John. We don't have the time or the audience.

[Lenore Epstein]

Perhaps newer holders are stronger?
True--at least if they use rare-earth magnets. Lee Valley does sell them, along with magnet cups & washers, but they're far cheaper from online sources, especially eBay, if you're an eBay-ing sort of person.

Anyhow, the 3" diameter rare earth magnet I scavenged from a gadget from Ace Hardware sticks so well to plane irons while I flatten the iron's back against abrasive stones (thereby protecting my fingertips from getting sanded off) that the only way to get it off the iron is to brace its side against a table edge, and push down on the blade firmly (using a rag to protect my precious fingers from edges and burrs) to slide it off sideways. That's totally fine, though, because the cool little thing literally saves my skin.

But after my favorite flathead screwdriver spent a few weeks stuck to the magnet it was so strongly magnetized that I had to guide it into a screw's slot with my free hand to keep it from trying to become one with the top of the screw. After reading this thread a few days ago I stuck the screwdriver's shaft to the magnet with the magnet's 'handle' aligned with the screwdriver so I'd remember which way to position it if it didn't work the first time.

I'm happy to report that today the screwdriver is only lightly magnetized--barely enough to move screws an inch or so away on a table, but not enough to pick them up or to stick stubbornly to anything. The magnet now lives in my waterstone box, which stores nothing ferrous at all, and I'm a happy camper again.

If I were shopping for a magnetic tool holder I'd look for one designed for light tools that either use a lot of weak magnets or well-spaced small rare earth magnets.

[Dan Hintz]

Yes, I can understand why you might think that. On the surface it doesn't seem logical that the weak magnetic field can magnetize anything. However, this is true. Here is an answer to this very question from the U of Illinois Physics department: https://van.physics.illinois.edu/qa/listing.php?id=436

In fact, making a magnet this way is a common science experiment for kids. To convince yourself, try it!
http://classroom.synonym.com/magnetize-things-6377.html - striking method
http://m.wikihow.com/Magnetize-Steel - method three
(Just remember that some types of ferromagnetic materials cannot be magnetized by any method.)


My original post said "negligible effect", and your first link also mentions the resulting magnet (after a good pounding, I might add) is quite weak (likely about enough to move a compass needle).

Your other two posts show metal acquiring a magnetic effect after rubbing with another magnet... not quite the same thing as leaving it in the magnetic field of the Earth.

[Geoff Whaling]

On a slightly different note about the potential downsides of strong magnetic fields and magnets in shops / sheds - a word of caution to turners who have surgically implanted medical devices - Pacemakers, Defibrillators, neuro stimulators, incontinence sacral nerve stimulators etc.

Read up on the cautions / warnings your device supplier has published on your device. Strong magnetic fields may interfere with the devices normal operation which could either get, messy, painful or result in an inappropriate therapy being delivered.

Magnetic tool holders at about chest height and strong magnets on headstocks are a particular risk for Pacemakers & Defibrillators.