• Scam Alert. Members are reminded to NOT send money to buy anything. Don't buy things remote and have it shipped - go get it yourself, pay in person, and take your equipment with you. Scammers have burned people on this forum. Urgency, secrecy, excuses, selling for friend, newish members, FUD, are RED FLAGS. A video conference call is not adequate assurance. Face to face interactions are required. Please report suspicions to the forum admins. Stay Safe - anyone can get scammed.

de-magnetize digital calipers

cuslog

cuslog

Super User
Premium Member
So, my (authentic, 8") ($300) Mitutoyo digital calipers jaws have become magnetic. I do have a commercial de-magnetizer but something tells me to not use it to de-magnetize these calipers.
Comments ?
 
cuslog said:
So, my (authentic, 8") ($300) Mitutoyo digital calipers jaws have become magnetic. I do have a commercial de-magnetizer but something tells me to not use it to de-magnetize these calipers.
Comments ?
Click to expand...
What do you have for a demagnitizer? Many of my tools are magnetized including calipers to some degree, and I wish I could "wash" them free of that.
 
I tried the one mentioned in the HM link, it was basically ineffective.
1739895468920.png
 
I stupidly inflicted my own pain by measuring magnets - don't ever do that -
But I also have heard that jaws can can become magnetized over time. Some steels I've machined exhibit magnetized 'fur' during cutting so I guess its possible to transfer that to tooling although one would think they pick a resistant alloy on expensive instruments at least. Seems like you hear about it more on calipers but not micrometers? Its a PITA in any event. I never ended up buying a demagnetizer but I can see where one might come in handy
 
Janger said:
Why wouldn’t you? What are you thinking?
Click to expand...
I'm thinking that these calipers "read" a magnetic strip ?
Am I wrong ? I hope so because I find the magnetism annoying ie; the jaws pick up tiny bits of swarf and I'm constantly having to wipe off the jaws and it sometimes takes 2 or 3 wipes to get it off.
I was afraid that de-magnetizing the jaws might also "kill" the strip that they read.
The de-magnetizer I have, I bought off Amazon a couple years ago ... about $100 or so ... I don't see them there anymore... they're not real great, will de-mag a screwdriver or dial calipers but I wanted to de-mag 1.375" dia. 4150 modified, HT that was quite strongly magnetized (I've been told its a side effect of the HT process of this particular alloy). It did work but took several passes over it to fully work.
 
I believe they are capacitive not magnetic. I need to demagnetize my calipers, as well as some 1-2-3 blocks and other stuff that got magnetized by the magnetic chuck on the surface grinder.
 
I made demagnetizer myself when I was using reel to reel tape recorder and magnetic heads are got magnetized after some time. I was using choke with winding without closing "I" - only "Es" . That is creating 50/60Hz sinusoidal magnetic field that is casing to multiple re-magnetizing of the iron and, as a result, iron part loosing "magnetics". You need slowly and gently move powered choke in, then make few passes right and left and then slowly move choke away.
 
CWelkie said:
Here is another option to try - Canadian vendor too! Or, you could of course replicate the design on your own.

Rotary Demagnetiser - Gray Drafting and Design
Click to expand...
I'm sure it works. All that rig is doing is creating an alternating N/S magnetic field that rotates. This is exactly what an electric motor does to create rotation. But used as a demagnetizer, it does not require a motor to spin it.

I don't know about you guys, but it seems to me, that because nowadays my shop is full of inverter technology, things seem to acquire magnetism on their own.
 
You must log in or register to reply here.
Back
Top