Samarium Cobalt magnets for oil filter?

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In the past I had used a Filter Mag on the side of my oil filter and when I cut open the filters it did catch a lot of really fine metal residue. Over time the filter mag kept loosing it's strength until eventually it wouldn't hold to the filter any longer. They use Neodymium magnets which aren't the greatest for keeping their magnetic powers under prolonged heat conditions.

I found some Samarium Cobalt magnets online at a decent price and these are supposed to be great for really high heat conditions so I was wondering if anyone else used these with good results over the long term?
 
Interesting. How long were the magnets in service before they started noticeably losing strength, and how long before it because nearly useless?

I always poo poo'd on those who used filter mags, but have recently changed my mind. I purchased a dozen neodymium bars, but only installed a few, to check the impact of heat after a few OCI's. the rest are holding tools up on my bench or on the fridge (though they're kind of a pain for the fridge, since they're so strong...)

I'll have to look into the Samarium Cobalt magnets - thanks for sharing!
 
StevieC I found some Samarium Cobalt magnets online at a decent price and these are supposed to be great for really high heat conditions so I was wondering if anyone else used these with good results over the long term? [/quote said:
I used samarium cobalt magnets to make my own magnetic drain bolts. I have one in my sons elantra, one to go in my elantra at the next oci.
No long term results yet.

https://bobistheoilguy.com/forums/ubbthreads.php/topics/4465589

Bottom of page 2
 
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Originally Posted By: gathermewool
Interesting. How long were the magnets in service before they started noticeably losing strength, and how long before it because nearly useless?

I always poo poo'd on those who used filter mags, but have recently changed my mind. I purchased a dozen neodymium bars, but only installed a few, to check the impact of heat after a few OCI's. the rest are holding tools up on my bench or on the fridge (though they're kind of a pain for the fridge, since they're so strong...)

I'll have to look into the Samarium Cobalt magnets - thanks for sharing!


At year 5 is when it was noticeable and year 8 is when it couldn't hold on any longer. About 300K miles (500,000km's) The Santa Fe died shortly there after from a broken Camshaft.
 
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Originally Posted By: spasm3


I used samarium cobalt magnets to make my own magnetic drain bolts. I have one in my sons elantra, one to go in my elantra at the next oci.
No long term results yet.

https://bobistheoilguy.com/forums/ubbthreads.php/topics/4465589

Bottom of page 2



Yeah that is why I thought it would be great to put them on my oil filter. It was your post that I realized there was a difference.
 
Originally Posted By: StevieC
Originally Posted By: gathermewool
Interesting. How long were the magnets in service before they started noticeably losing strength, and how long before it because nearly useless?

I always poo poo'd on those who used filter mags, but have recently changed my mind. I purchased a dozen neodymium bars, but only installed a few, to check the impact of heat after a few OCI's. the rest are holding tools up on my bench or on the fridge (though they're kind of a pain for the fridge, since they're so strong...)

I'll have to look into the Samarium Cobalt magnets - thanks for sharing!


At year 5 is when it was noticeable and year 8 is when it couldn't hold on any longer. About 300K miles (500,000km's) The Santa Fe died shortly there after from a broken Camshaft.


Only 300k miles. Id be POd
smile.gif
.

We have some high expectations of cars nowadays.
 
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I've used individual magnets and a PAIR of FilterMags for 4 yrs or so, no issues.

But when you select individual bar magnets, be sure they're about 3/16" wide max, otherwise
the won't stick fast to the radius of the filter housing and may 'rock' a little, this means
some or most of the magnetic field is not cleanly coupled to the filter housing thru to
the inside. It seems counter-intuitive, but long narrow magnets generate a strong narrow
field that picks up well inside a filter!

ALL magnets have a specified max operating temp spec (& currie point) so if you chose low temp neodymium
OR samarium cobalt you may not be happy after a while. Realistically you may lose 20% or so.

(Low temp magnets have a currie point of about 350F where they die completely. In a engine oil application
you won't hit that on a family hauler)

Min operating temp for most is 175F, then 200- 250F and up. The kicker is if you overdo it and pick the
highest possible, they'll be weaker out of the box as a trade off for really hi operating temps.

For filter applications you wanna be 200F to 250F, not more then that.

TIP: If you order magnets, be sure they're magnetized thru the sides, not the ends. In the old days
kids magnets were only strong at the ends. For filter use you want the N / S poles to be on the long sides
of the magnets you chose ("magnetize thru it's thickness). Manufactures may offer magnets with different
"magnetic orientations".

Take a look at some the pics in this PDF:

FILTERMAG vs HOMEBREW
https://app.box.com/s/uxvu8dmscf5wcgftutdm0ejqwgn86tw7

A good place to order magnets is KJ Magnetics on the web.... or is 'JK'? close enough! gotta check again..
 
Originally Posted By: i_hate_autofraud


ALL magnets have a specified max operating temp spec (& currie point) so if you chose low temp neodymium
OR samarium cobalt you may not be happy after a while. Realistically you may lose 20% or so.

(Low temp magnets have a currie point of about 350F where they die completely. In a engine oil application
you won't hit that on a family hauler)

Min operating temp for most is 175F, then 200- 250F and up. The kicker is if you overdo it and pick the
highest possible, they'll be weaker out of the box as a trade off for really hi operating temps.




Samarium cobalt magnets are not low temp, thats why i chose them. They lose strengt at 300c.



Available+Materials+Two+types+of+permanent+magnet+are+generally+used+%E2%80%93+Samarium+Cobalt+%28SmCo%29+and+Neodymium+Iron+Boron+%28NdFeB%29.jpg
 
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Sapsm3, thanks...
smile.gif


Yeah 300 Celsius is 572 degrees Fahrenheit, way lower than my oil filter will see.
thumbsup2.gif
 
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