But that’s zinc shot… It doesn’t even look like steel. It shouldn’t be attracted to a magnet. Perhaps they’re steel inside, but the outside is clearly zinc.
Zinc has a characteristic light bluish tint and oxidizes to white, not yellow or brown. Some of them appear slightly dull and oxidised with a grey or white layer.
And how do you propose to know how blue-tinted those balls are without being able to tell what they’re reflecting and what the camera’s white balance is set to?
I blurred the image and took a few colour samples; the balls are grey in the image, with very slightly more red in them than green or blue. That doesn’t mean they’re actually grey; they could be slightly blue and reflecting a slightly red scene or vice versa. They could be slightly green but the camera settings have “corrected” it to look grey.
How can you tell that the “dull” ones are oxidised, as opposed to roughened, blurred due to movement or covered with some other substance like lubricant?
All excellent points! I concede to your deeper consideration. (Though I do think that a “roughened” ball bearing would rather prove my point for me, and that those which appear roughened are largely also those under other balls, lessening the chance that they are moving)
I soon expect to have screws implanted in my spine. I also have other infirmities. I hope like hell to never have screws ripped through my vertebrae by an MRI.
I think, as someone else said, things installed into the body are usually titanium and thus non ferrous. Fortunately they don’t generally cause issues with MRIs as a result.
(I only know this because when I broke my ankle, during the pre-surgery interview, I asked the surgeon about going through metal scanners at an airport.)
Usually titanium, but yeah sometimes medical stainless steel. Both are non-ferromagnetic, especially titanium. These balls look like they could well be normal steel or any other metal. Also, implants - unlike these metal balls - are usually screwed firmly into your bones. So yeah, implants should be mostly fine on MRI. Loose balls of dubious metal? Wouldn’t advise it. Keep in mind MRIs are literally powerful enough that metals in tattoo ink can even be an issue - which the article you linked mentions itself.
I think its not about the property of beeing a metall ist a bout beeing ferromagnetic (In that case probably not an issue because these bearing balls are usually out of some kind stainless steel. )
I was told that because I have stents (plastic coated with platinum) I can never get an MRI again by my cardiologist.
A friend who makes knives felt the little bits of metal that he’s picked up in his skin over years of grinding blades getting pulled out of him during an MRI.
Maybe aluminum foil in your pocket would only “interfere with the scan,” but those magnets are powerful enough to make any metal in your body come out, violently.
I know someone with metal pins in their leg and they have had a MRI. It depends on the metal. Since I didn’t specify what kind of metal everyone rushes forward to speculate on how wrong I am.
Not at all, I was simply pointing out why you were wrong. You’re hallucinating this supposed importance that everyone places on you being wrong.
This is at least your second comment of you complaining about someone disagreeing with you, so maybe your last sentence is projection and you’re the one who’s feels powerless in your life?
MRIs work because strong enough magnetic fields will interact with any material, not just ferrous metals. This can be impacted by the structure said materials form (stents are a weave like a finger trap and therefore more prone to interaction with magnetic fields than say a solid cylinder) but I’d be inclined to say your friend was lucky. Ball bearings like in the OP are nearly always steel outside of specific high end applications and therefore would behave like they were coming out of a shotgun shell.
Nothing you are going to type here is going to change the comments made by the tech operating the imaging system while I’m testing network connections right next to him around fifteen years ago.
A little metal wont kill you. It will ruin the image.
Metal will ruin a CT scan. Metal will kill you in an MRI machine.
But that’s zinc shot… It doesn’t even look like steel. It shouldn’t be attracted to a magnet. Perhaps they’re steel inside, but the outside is clearly zinc.
https://www.ausrad.com/exams-services/magnetic-resonance-imaging/can-i-have-an-mri-if-i-have-metal-in-my-body/
Isn’t that just because they use non-magnetic metals for implants?
Titanium, afaik
And that’s zinc shot. Perhaps they’re steel inside, but the outside is clearly zinc.
How on earth can you tell the difference between steel and zinc at a glance?
Zinc has a characteristic light bluish tint and oxidizes to white, not yellow or brown. Some of them appear slightly dull and oxidised with a grey or white layer.
And how do you propose to know how blue-tinted those balls are without being able to tell what they’re reflecting and what the camera’s white balance is set to?
I blurred the image and took a few colour samples; the balls are grey in the image, with very slightly more red in them than green or blue. That doesn’t mean they’re actually grey; they could be slightly blue and reflecting a slightly red scene or vice versa. They could be slightly green but the camera settings have “corrected” it to look grey.
How can you tell that the “dull” ones are oxidised, as opposed to roughened, blurred due to movement or covered with some other substance like lubricant?
All excellent points! I concede to your deeper consideration. (Though I do think that a “roughened” ball bearing would rather prove my point for me, and that those which appear roughened are largely also those under other balls, lessening the chance that they are moving)
I know it’s my name, but I have to congratulate you on the excellent pedantry!
This isn’t an implant though. Massive difference.
I soon expect to have screws implanted in my spine. I also have other infirmities. I hope like hell to never have screws ripped through my vertebrae by an MRI.
Implants are non-magnetic. Wrecks the image, though.
Hopefully they don’t need to do an MRI of my spine after they operate on it - apparently for their sake, not mine.
I hope you’ll recover quick and get rid of your health problems!
Thanks!
Ugh, yeah, how do they even do MRIs for people with metal parts?
I think, as someone else said, things installed into the body are usually titanium and thus non ferrous. Fortunately they don’t generally cause issues with MRIs as a result.
(I only know this because when I broke my ankle, during the pre-surgery interview, I asked the surgeon about going through metal scanners at an airport.)
Non ferrous metal.
What are implants made of? Stainless for the most part.
Usually titanium, but yeah sometimes medical stainless steel. Both are non-ferromagnetic, especially titanium. These balls look like they could well be normal steel or any other metal. Also, implants - unlike these metal balls - are usually screwed firmly into your bones. So yeah, implants should be mostly fine on MRI. Loose balls of dubious metal? Wouldn’t advise it. Keep in mind MRIs are literally powerful enough that metals in tattoo ink can even be an issue - which the article you linked mentions itself.
I think its not about the property of beeing a metall ist a bout beeing ferromagnetic (In that case probably not an issue because these bearing balls are usually out of some kind stainless steel. )
Neodymium magnets?
These aren’t bearing balls. They’re zinc shot. Perhaps they’re steel inside, but the outside is clearly zinc.
We get it, zinc shot man.
False.
I was told metal interferes with the scan. By a guy doing the scan.
I was told that because I have stents (plastic coated with platinum) I can never get an MRI again by my cardiologist.
A friend who makes knives felt the little bits of metal that he’s picked up in his skin over years of grinding blades getting pulled out of him during an MRI.
Maybe aluminum foil in your pocket would only “interfere with the scan,” but those magnets are powerful enough to make any metal in your body come out, violently.
I know someone with metal pins in their leg and they have had a MRI. It depends on the metal. Since I didn’t specify what kind of metal everyone rushes forward to speculate on how wrong I am.
The post is obviously insinuating that these are iron balls, so in this context you are wrong.
Its important to you I be wrong. How powerless you must be in your day to day life.
Not at all, I was simply pointing out why you were wrong. You’re hallucinating this supposed importance that everyone places on you being wrong.
This is at least your second comment of you complaining about someone disagreeing with you, so maybe your last sentence is projection and you’re the one who’s feels powerless in your life?
Sounds like a sad way to live.
Except that they’re clearly zinc shot. I think the poster made a funny without realising that they aren’t steel, unless it’s zinc-coated
MRIs work because strong enough magnetic fields will interact with any material, not just ferrous metals. This can be impacted by the structure said materials form (stents are a weave like a finger trap and therefore more prone to interaction with magnetic fields than say a solid cylinder) but I’d be inclined to say your friend was lucky. Ball bearings like in the OP are nearly always steel outside of specific high end applications and therefore would behave like they were coming out of a shotgun shell.
Nothing you are going to type here is going to change the comments made by the tech operating the imaging system while I’m testing network connections right next to him around fifteen years ago.
https://lemmy.world/comment/22259258
Yes Metals in general shild RF-Waves used to sample the image (and could get hot by that process)
Metal in a CT machine = bad image
Metal (particularly ferromagnetic metal) in an MRI machine = injured patient
Check out the stapler bouncing around near the beginning of this video: https://youtu.be/6BBx8BwLhqg