re-magnetising magnetic base

My mag base is pathetic - my 5/8" Eclipse 'pots' grip better!

Is there anything that can be done, eg dismantle and replace magnet, or is there someone offers a re-magnetising service? Or shall I just but another?

Never heard of a re-magnetising service, if the useless one is a far eastern object it may have been cr*p from the start & a similar replacement could be the same? Back in the day Eclipse etc were decent items.

Tony

Folk who offer magneto winding services may be able to remagnetise it for you…

Eclipse in Sheffield will remag chucks - not sure if they only do their own. Costs about £75 I think.

https://www.eclipsemagnetics.com/resources/

John

I have a 3"x3"x4" magnetic V block, the Alnico magnet of which has lost most of its strength (the reason it was scrap at work). I bought five wickedly powerful NIB magnets and have plenty of aluminium and steel to make a new rotor for it.

I'm still short of the round-to-it that is neccessary for the repair job.

Eclipse do other makes of chuck repairs but I have never had a mag base repaired. Worth a telephone call to Sheffield just up the road from Meadowhall. Perhaps droping better half of shopping whilst you drop it off.

David

I have some experience of using a remagnetiser ...

It had a gapped square iron framework where the gap was bridged by the magnet and matching pole pieces for the individual magnet. The cross section of iron framework was at least double that of the target magnet.

Around the framework was wound a pair of huge coils that could be connected in parallel or series for 110V or 220V operations.

A push button switch connected the mains power to a bridge rectifier follwed by a DC ammeter and the two coils.

When the button was pushed the current slowly (over a few seconds) rose until a maximum was observed and the button released.

Tired old magnets were revitalised to (in my estimate) 2 or 3 times their previous strength.

Commercially speaking, we found this old piece of junk, fixed it up for a few 10s of dollars, used it on every permanent magnet in our Western Desert base and then returned it to its hiding place under a bench. We had a serial number of 00006 riveted to the base plate of the device while the company had >100 bases worldwide. I had never seen a magnetiser before nor did I ever see one again.

If I needed to do something like that I would be thinking about using my DC inverter welder to provide the necessary current. It can do 200 Amps, and has its own built in current limiting so it is not going to complain if it is connected to a coil of heavy wire. Then it would be just a matter of making up a magnetic circuit with the coil of heavy wire around it. It doesn't actually take very long to remagnetise things, long enough for the field to build up to the maximum, which is going to be in milliseconds rather than seconds.

Another approach is to use a car battery and a coil.

John

Thanks everyone for your interesting contributions. So, no simple solution. I will buy a replacement and relegate the old one to holding a 12v light. Do secondhand Eclipse bases tend to retain holding power into old age?

Rob, I have an Eclipse magnetic base purchased new by me and its close to 60 years old and in constant use so yes they live a long life !

John

Hi Rob, this is my Eclipse magnetic base, I don't know exactly how old it is or how strong it was to start with, but I know it is more than 50 years old and it is hanging on to 7Kg without any sign of letting go. It has never been serviced in that 50 years, so I agree with JohnF and the surface finish it is holding, looks the same as the one in the facing view but not as wide.

Regards Nick.

Please may I piggyback on to the original question?

I have a push button magnetic base similar to the one on Nick Farr's photo above, even including the sloping part on the top. But, it isn't an Eclipse. In fact it doesn't show a manufacturer. But it does have a label fastened just as Nick's is, and on the same face too.

Anyway, to cut the waffle (!), mine can be very stiff to operate, so much so that I have, at various times, removed the front label (and glued it back on!) and sprayed WD40 inside and outside, ie around the push button in an attempt to free it off. This, I must admit was well before I learned about the negative aspects of WD40, so please don't bother telling me off. So, the question is, therefore, how can I ease the button operation such that it doesn't almost involve a thumb dislocation. FWIW, I have two other magnetic bases, both lever operated, and both being much easier to use. Incidently, I don't recall the WD40 having much of an effect, hence I now just put up with it's stiffness to the extent that rather than switch it off, I use brute force to remove it from wherever it has been used, and keep it on a piece of 6mm thich steel plate with a piece of polythene between the magnetic base and the steel plate.

Cheers,

Peter G. Shaw

Peter have you tried just adding some oil around both ends of the button and allowing it to wick in?

Can't guarantee that it will work, but worth a shot!

Howard

Howard,

Since the WD40 didn't work, and then I learned about the WD40 problems, I haven't done anything. I'm wondering if it may be worthwhile placing it in a jamjar with sufficient light oil to allow the device to be submerged. Beginning to sound like an experiment coming up, perhaps in the winter months (when it's too darned cold to do anything). Obviously it would then need to drain for a while.

Peter

Hi Peter, my Eclipse one has and always has had a stiff kind of operation, but I think there maybe a spring inside as it will not stay in the switched on position unless it is on a surface that will keep a magnetic circuit of a sufficient level, i.e. it will not hold onto a rough surface, slightly uneven or a small area. I've no idea if any oil will help with yours.

Regards Nick.

I also have gone through the problem of an extremely stiff push button on an Eclipse base. I tried various methods of easing, paraffin, clock cleaner and WD40. Nothing worked so eventually I put it in a club auction and bought a new switch type, vastly superior can now turn it on and off with two fingers.

On the subject of remagnetising, many years ago as an apprentice I was given the rask of constructing a magnetiser for magnetron magnets. This was at a division of GEC that manufactured valves and cathode Ray tubes, a laboratory lash up had been made to prove the process and my job was to make the whole thing into a workable device in a cabinet that could be used in production. The details are now quite hazy but basically a simple power supply charged up a huge bank of capacitors and when they were fully charged the charge was released via a device called an ignetron into a length of very heavy copper braid which had been tightly wound around the metal shape that was to form the magnet. The one thing that has always stuck in my mind was that the magnet being charged would leap 2 - 3 feet in the air as the charge was released. I can't recall exactly what was done in the production process to stop this happening, the only thing I do remember was the whole process was carried out on a wooden bench in a fairly substantial wooden cupboard. Phil

Nick & Philip,

Thanks for that confirmation - it is nice to know that I am not alone with this problem.

Nick,

I don't have any sort of problem with it maintaining the "on" position. Nor do I have any problem with it not holding on rough etc surfaces. I do have a slight problem with the power of the magnet as it's not as strong as the two lever magnetic bases I have. But it's usable with care.

Right then, as I mentioned two posts above. An experiment will shortly be forthcoming. Remove the label, perhaps a good clean with paraffin and then a soak in possibly some "68" oil I bought for the lathe slides. If I can get on with it (note the careful avoidance of the "round tuit" there!) I'll see about setting it up this week - provided my poor old clapped out, cream crackered body can be persuaded to withstand a bit of light work. And then I can leave it until mid-August, ie after 2 weeks in the caravan. Yay-hay!

Peter G. Shaw