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Have a magnetic vice . Has lost practically all its magnetism . Is there anyway to magnetize again . Attached photos thanks in advance

There is such a thing as a magnetic vise. I saw them in catalogs a few decades ago, but never bought one.

The thing in post #1 is called a round permanent magnetic chuck. If you need one that works, you probably have to buy a new one. They do not improve with age, though the Japanese 6 x 18 permanent magnetic chuck on my surface grinder, bought new in 1979, still works, so they do not naturally die either. I think I read somewhere that they die if you take them apart without knowing a trick of some sort. I do not know that trick, and never needed to take one apart.


Larry
 
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I have the same chuck,its a Cleveland IIRC..........and the force is weak ,as they say ..........these old chucks with alnico or some other metal magnet were never particularly strong ,compared to electric ones.............modern ceramic magnet ones are strong,but the magnets can break up into gritty fragments that jam the mechanism.
 
There is such a thing as a magnetic vise. I saw them in catalogs a few decades ago, but never bought one.

The thing in post #1 is called a round permanent magnetic chuck. If you need one that works, you probably have to buy a new one. They do not improve with age, though the Japanese 6 x 18 permanent magnetic chuck on my surface grinder, bought new in 1979, still works, so they do not naturally die either. I think I read somewhere that they die if you take them apart without knowing a trick of some sort. I do not know that trick, and never needed to take one apart.


Thanks Larry
I have a 10$ paper weight . Will ck out link on magnetic Chuck
 
When you remove magnets like in motors and generators you must use soft iron keepers. These contain the magnetic flux and rechannel it back into the magnet. A fraction of a second without them and many of the atoms spins randomize and will not go back into line without then entire magnet being degaused and remagnetized.
A horseshoe magnet always comes with a little keeper bar. Leave it off and, the magnet not holding onto some iron, it will slowly loose power.
Bill D
 
I had a similar situation albeit on a smaller scale. I had a small magnetic spindle which consisted of a brass tube with a ring gear pressed around it, two ends pressed into it, and between the ends a cylindrical magnet. I took it apart and it lost it. I bought a stack of 1" diameter grade 52 neodymium cylindrical magnets and used it instead of the dead cylindrical magnet and now it is much stronger than ever. This on a magnetic pattern tracing torch.

metalmagpie
 
Most manual magnetic chucks lose magnetism instantly if you dismantle them. The Eclipse user manual states specifically that they must be re-magnetised if even dismantled for an instant.

View attachment 411455
Thanks for the info I had no idea . The magnets were so weak . Taking apart didn’t matter . Good base for something
 
Someone will correct me if I'm wrong but...
I believe I read that those chucks are magnetized at the factory by a machine that charges up a bank of large capacitors. Then that charge is shorted through a heavy duty coil that surrounds the object to be magnetized. That produces a huge momentary flow of electricity that creates a very powerful magnetic field. Doesn't sound like something that could easily be done in one's garage or shop.

I've magnetized countless screwdrivers (and a few pliers) by stroking a magnet along the shank of the driver but the end result isn't super powerful. However, it's plenty strong for holding a screw to the screwdriver tip.
 
Someone will correct me if I'm wrong but...
I believe I read that those chucks are magnetized at the factory by a machine that charges up a bank of large capacitors. Then that charge is shorted through a heavy duty coil that surrounds the object to be magnetized. That produces a huge momentary flow of electricity that creates a very powerful magnetic field. Doesn't sound like something that could easily be done in one's garage or shop.

I've magnetized countless screwdrivers (and a few pliers) by stroking a magnet along the shank of the driver but the end result isn't super powerful. However, it's plenty strong for holding a screw to the screwdriver tip.
I have several demagnetizers that use AC power in a coil, both the watchmaker type (watch passes through the coil) and the machine shop type (coil is below a flat surface). In either case, you slowly pull the watch or steel part/tool away from the energized coil to remove magnetism. If you turn off the power while the item is in the coil or resting on the flat surface, it will be more or less magnetized. As was said, enough to make a screw stick to a screwdriver, but not near as strong an attractive force as a modern permanent magnet.

Larry
 
If the magnet segments are a standard rare earth style or you can stack standard styles to match the oe ones then all your problems will be solved and the chuck will be many times stronger than it ever was. The nice thing about rare earth magnets they don't loose magnetism when they are dissasembled and don't need a keeper.
I did that to a magnetic angle block that had Alnico magnets that lost just about all their magnetism . Since it was used I don't know how it happened. I used 50 lb magnets. Did a thread on it a few years ago.

I think all the permanent mag chucks made now have rare earth magnets. The prices are also really cheap for the imported ones so you might check and see what a new one costs as it may be cheaper than trying to fix yours.
 
Someone will correct me if I'm wrong but...
I believe I read that those chucks are magnetized at the factory by a machine that charges up a bank of large capacitors. Then that charge is shorted through a heavy duty coil that surrounds the object to be magnetized. That produces a huge momentary flow of electricity that creates a very powerful magnetic field. Doesn't sound like something that could easily be done in one's garage or shop.
This is pretty much how the magnetizers work, but with one addition: To magnetize a chuck like the one pictured, there would be a special shaped coil and perhaps a laminated silicon steel pole piece to shape the field to couple directly into the chuck magnetic system and thence to the magnet within. The iron pole works for alnico and ferrite, but not rare earth magnets.
 
We used to magnetize old round files for removing the swarf in deep holes by holding them inside the field created by the spot welders on the Toyota assembly line when I was an apprentice.
 
Lucas magnetos had a special magnet metal that was 'self keeping' .........however the instruction book also gives specs for remagnetising .....and quotes "80,000 ampere turns " as the minimum capacity of the coil needed ...............there are lots of people around who remagnetise old magnetos .
 
Lucas magnetos had a special magnet metal that was 'self keeping' .........however the instruction book also gives specs for remagnetising .....and quotes "80,000 ampere turns " as the minimum capacity of the coil needed ...............there are lots of people around who remagnetise old magnetos .
No Lucas magnetos don't have a special magnet metal that is self keeping. They use ALCINO magnets starting in the 1930's which are not special or unique. Taking the armature out of the magneto body and you will lose 20% of the magnetism. Now Lucas knew owners would take the mag apart and had no access to get it magnetized again so it had a built in safety factor to still work OK without being re-magnetized.


As for the fixing the magnetic vice, constructing a magnetizer will cost far more than the cost of a new chuck.

And magnetizers and de-magnetizers both work the same way. To magnetize you use DC current. To de-magnetize you use AC current. The magnetizer will however be a lot bigger.
 
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The best quick magnetize Ive seen was a crane boom .......It was so magnetic from touching power lines,when I tried to weld on it ,the weld metal would be pulled away sideways.
 








 
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