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Demagnetizer Recommendations

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I've got a movement that I think is magnetized. The hairspring coils are sticking and it makes a compass needle jump when placed over it. Here's a pic of the timer reading:

 

AS_1880_magnetized.JPG

 

 

I've watched Mark's videos and so I'm shopping for a demagnetizer. I'm looking at the Etic for about $80 shipped, the similar C&H model for about $30 shipped, the generic clones for $10 or so from China, this bad boy from Amazon (too heavy duity?) and some vintage Vigor demagnetizers. I'm a little (a lot) tool nutty and I hate buying really cheap and then spending again for one that works. Any recommendations?

 

Also, just for fun I was playing with the super slow speed function on my camera last night and made this video. Not great quality, but may be of interest.

 

https://youtu.be/JpLEB0kiHw0

 

Thanks,

 

Don

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If you can afford the Etic, then go for it - I melted mine by leaving it plugged in and mistakingly setting a book on top of it which pressed the button down :D

I since purchased one of the Chinese ones to see what it was like and it works just fine.

 

The Elma I have in my video is an electronic one and it is good but IMO seems to do no better than the cheap chinese one, it is just very convenient to use.

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I was going to get one of the Chinese ones as my next tool purchase.  The 3 Dumont tweezers I got from my watchmaker desk purchase are all magnetized so I defiantly want to fix that so I can start using those great tweezers.

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Thanks for the input Mark. I got the Etic for about $68 shipped. Assuming it's in stock, I'll have it tomorrow or the next day. I'll keep it away from books and I'll update this post when I get to use it. :D

 

Blake, how's the bench? Did you re-stain it?

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I'm leaving the stain till the end.  I have one of the drawer fronts that is trashed and another that has fallen apart and will need a few pieces replaced.  I got my father-in-law's router for this but need to buy the correct bits for the recessed drawer pulls.  Once I have those sorted I want to replicate the rails that would have originally be on the sides an back to hopefully catch pinging parts then move on with the stain. 

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I'm leaving the stain till the end.  I have one of the drawer fronts that is trashed and another that has fallen apart and will need a few pieces replaced.  I got my father-in-law's router for this but need to buy the correct bits for the recessed drawer pulls.  Once I have those sorted I want to replicate the rails that would have originally be on the sides an back to hopefully catch pinging parts then move on with the stain. 

 

Nice! I hope you'll post the finished piece when you're done.

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I am working with an NMR spectrometer which is 94000 Gauss :) Sure my watch was magnetized, it even stopped once i forgot to take off before going close to the magnet. Since i had a suitable transformer and remaining wire from generator rewireing decided to put together a demagnetizer yesterday. Used the middle of an empty bottle as the coil shape, it is big enough for all sized watches, even for my Roskopf pocket watch :) The 230V/60Hz main current is transformed to 12V/60Hz with a toroid transformer. The wire is 0.7mm in diameter and four layers were wound. It is connected directly to the transformer... well, burned some 800mA fuses when connected to quickly with a switch :) but working fine with a crocodile forceps. The copper layer under it is for cooling. It is heating up over 60 Celsius in 30 seconds.

2016-05-19 06.13.15.jpeg

Before demagnetization the gauss meter (android app) shows up to 3 Gauss.

before demagnetization.jpeg

The peak is only 0.34 Gauss after demagnetization :) The rate increased by ~10 s/d, amplitude is the same and it is more stable in the different positions. 

after demagnetization.jpeg

Finally demagnetized all of my steel tools. Never again sticky screws :)

 

Edited by szbalogh

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de  magnetize /  de GAUSS :  I have a couple old watchmakers de magnetizers.  there is a button to  hold down  when  passing AN   ITEM  thru  (in and out)  of the coil.   this  means  there is  no  power on when  left un attended.    I  like that  GAUSS  meter.  vlnn  

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21 hours ago, oldhippy said:

You are right, the beat error increased a bit from around 0.3 to 0.5 - 0.6ms. I will introduce some light bulbs to the high Voltage side to reduce the power.

19 hours ago, vinn3 said:

de  magnetize /  de GAUSS :  I have a couple old watchmakers de magnetizers.  there is a button to  hold down  when  passing AN   ITEM  thru  (in and out)  of the coil.   this  means  there is  no  power on when  left un attended.    I  like that  GAUSS  meter.  vlnn  

The magnetic sensor in my smartphone is on the top right corner of the display. Google says that usually it is in the top left corner. You need to place the watch directly over the sensor to measure this small fields. 

Edited by szbalogh

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the proper tool  is  a  '"watchmakers  de magnetizer"  you  don't have to  worry about too strong a  magnetic field.  the  use of it is a separate subject,  as is  the  deturming if a watch is magnetized.   check out De Carle's book.

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Added a 60W bulb standing lamp to the 220V circuit which i was using anyway nest to my bench. Power reduced to around half and now it is heating slow but its effective like before. Tested with a screwdriver magnetized by a neodymium magnet :)  

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i love the video that you made. it's really the first time i've seen the escape wheel in full arc. is that the typical amout of "swing" that an escape wheel has? i thought that they had an almost full turn, but this one is about 270 degrees or so.

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Hi guys, I was just wondering if you could give me your opinion on which demagnetizer to go for. I am a hobbyist and i just service my own watches and any other movements i come across.

The options are all from cousins website and range from £2 to £160.

The cousins cube is £2 will this do the job? I guess you just slide the parts through it and job done?

Etic swiss is £30 and is mains powered.

Greiner and Elma also do demagnetizers around the £160 mark.

So, id really like your opinions, can i do this on the cheap at £2 or is it going to be wise to spend a little more? 

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You need a mains powered unit to generate an alternating magnetic field to be of any use in watch repair work.

Check out eBay and you will find many Asian versions of the Etic unit (which is almost certainly of Asian origin itself) for anything between £5 and £25. Since all it is is a coil and a switch there is little that can go wrong.

I have two units, an ancient pass through type that came in a job lot of tools and is great, and an Etic type that I paid about £7 for. They work as well as each other.

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I have used diy demagnetizers that work the same as the versions you list - basically a coil running of AC current - and they work ......ok. You have to remove your watch/movement/part etc slowly from the magnetic field and some times this does not work as one would hope. I have been thinking of building a automatic version for some time now, and  last week stumbled on this page while browsing the subject. Simple and genius - charge a capacitor and then use the capacitance and power stored to form a LC-resonator with a inductor - viola, an automatic demagnetizer!

In my version I use two 230V to 12V transformers for isolation.

Here in my version:

 

147764423593527500_resized.jpg

147764423637000800_resized.jpg

147764423216317700_resized.jpg

Charge for three seconds and then press DeMag and your done - works wonders and I am never going back to the coil version!

So if you can invest 60min of building time - I would go fo a automatic version!

 

Edited by RCDesign

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If you are just a hobbyist I can recommend this one from E-bay at £11.99. I have one, and although it looks rather crude it is very effective, certainly as a starter unit. You can always look at a more expensive one later on. This one not only demagnetises small things like watches, but it also demagged my kitchen sharpening steel. Just search 'watch demagnetizers' on E-bay. The 'Cube' is good for finding pinged parts off the floor!

PS. You may have to put a three-pin plug on it.

 

s-l225.jpg

Edited by fjseal

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On 30/10/2016 at 11:13 PM, fjseal said:

If you are just a hobbyist I can recommend this one from E-bay at £11.99. I have one, and although it looks rather crude it is very effective, certainly as a starter unit. You can always look at a more expensive one later on. This one not only demagnetises small things like watches, but it also demagged my kitchen sharpening steel. Just search 'watch demagnetizers' on E-bay. The 'Cube' is good for finding pinged parts off the floor!

PS. You may have to put a three-pin plug on it.

 


Thanks for the advice. I did see this one on eBay before. However I skipped past it, thought it looked a bit ropey. Good to know it can do the job, I will take a good look at it. Funny how we can be drawn to things by the way they look...

 

Edited by jdm
Please don't include pictures in quoting

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Yes they do work, a few folk on the forum have used them with success including myself.  When using one, hold the watch on or very close to it then press the button on the unit.  While holding the button down, slowly pull the watch away to a distance if 450-600mm before releasing the button.  Do not keep the button held down for longer than ten seconds at a time or the unit will overheat.  

You may have to repeat this a few times to get rid of the magnetism, but it's the same with any demagnetiser.  Don't assume that the movement will be demagnetised after one go.  Another thing to remember, it is possible to inadvertently magnetise a movement with a demagnetiser.  If this happens, just go through the process again until you get the correct result.

 

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