Cinfer FAQ

How is the pull force of each magnet determined?

All of the pull force values we specify have been tested in our laboratory. We test these magnets in two different configurations. Case 1 is the maximum pull force generated between a single magnet and a thick, ground, flat steel plate. Case 2 is the maximum pull force generated with a single magnet sandwiched between two thick, ground, flat steel plates. Case 3 is the maximum pull force generated on a magnet attracted to another magnet of the same type. The values are an average value for five samples of each magnet. A digital force gauge records the tensile force on the magnet. The plates are pulled apart until the magnet disconnects from one of the plates. The peak value is recorded as the “pull force”. If using steel that is thinner, coated, or has an uneven or rusty surface, the effective pull force may be different than recorded in our lab.

What materials can i use to block/shield magnetic fields?

Magnetic fields cannot be blocked, only redirected. The only materials that will redirect magnetic fields are materials that are ferromagnetic (attracted to magnets), such as iron, steel (which contains iron), cobalt, and nickel. The degree of redirection is proportional to the permeability of the material. The most efficient shielding material is the 80 Nickel family, followed by the 50 Nickel family.

What does Magnetized thru thickness mean?

We use the description “Magnetized thru thickness” to identify the locations of the poles on our block magnets. The thickness is always the last dimension listed for block magnets. If you take one of our block magnets and place it on a flat surface with the thickness dimension as the vertical dimension, the poles will be on the top and bottom of the magnet as it sits.For example: On one of our blocks of 1″ x 1/2″ x 1/8″ thick (25.4 x 12.7 x 3.17mm). If you place one of the blocks so it is on a flat surface with 1/8″ (3.17mm) as the vertical dimension, the poles will be on the top and bottom as the magnet sits. This means the poles are located in the middle of the 1″ x 1/2″ sides (25.4 x 12.7mm).

How can i dentify the poles of the magnets?

There are several simple methods that can be used to identify the (Scientific) North and South poles of neodymium magnets.1)The easiest way is to use another magnet that is already marked. The North pole of the marked magnet will be attracted to the South pole of the unmarked magnet.2)If you take an even number of magnets and pinch a string in the middle of the stack and dangle the magnets so they can freely rotate on the string, the North pole of the magnets will eventually settle pointing North. This actually contradicts the “opposites attract” rule of magnetism, but the naming convention of the poles is a carry over from the old days when the poles were called the “North-seeking” and “South-seeking” poles.   These were shortened over time to the “North” and “South” poles that we know them as.3)If you have a compass handy, the end of the needle that normally points North will be attracted to the North pole of the neodymium magnet.4)Use Pole Identifier Devices.(Please note: In some magnetic therapy applications, the definitions of the poles are reversed from the scientific definition described above. Please be sure to confirm the proper definition of the poles prior to using magnets for medical purposes)

What is the difference between the different platings and coatings?

The coatings do not affect the magnetic strength or performance of the magnet.The preferred coating is dictated by preference or by the magnets intended application.Nickel is the most common choice for plating neodymium magnets, and is actually a triple plating of nickel-copper-nickel.It has a shiny silver finish and has good resistance to corrosion.Black nickel has a shiny, black/charcoal appearance and is slightly more corrosion resistant than regular nickel.It is also a triple plating of nickel-copper-black nickel.Zinc has a dull gray/bluish finish,that is more susceptible to corrosion than nickel. Zinc can leave a black residue on hands and other items.Epoxy is basically a plastic coating that is virtually 100% corrosion resistant as long as the coating is intact.From our experience, it is the least durable of the common coatings.Gold plating is applied over the top of nickel plating, so gold plated magnets have the same characteristics as nickel plated ones, but with a gold finish.

Do you stock any unplated magnets?

As mentioned above, the iron in the NdFeB material will oxidize if it is exposed to moisture. For this reason, we do not stock any unplated magnets. We can supply unplated magnets as custom order items.

Can you just put my magnets in a samll envelope to save postage?

No. If they are being sent by airfreight, all magnets must be shipped in a box in order to comply with United States Department of Transportation, USPS, UPS, and FedEx regulations for the shipment of magnetic materials.

Will magnets harm my electronics?

Mayb The strong magnetic fields of these magnets can damage certain magnetic media such     as floppy disks, credit cards, magnetic I.D. cards, cassette tapes, video tapes or other such devices.   They can also damage televisions, VCRs, computer monitors and other CRT displays. Never place neodymium magnets near any of these appliances.   As for other electronics such as cell phones, iPods, flash drives, calculators and similar devices that do not contain magnetic storage media, probably not, but it is best to err on the safe side and try to avoid close contact between neo magnets and electronics.

Will magnets erase my hard drive or harm my computer?

Not unless you really work at it. While you probably don’t want to stick magnets directly to your computer case, having them nearby will not harm your computer. Magnets can damage floppy disks and magnetic tape storage media, so you must keep magnets away from these items. They will not, however, damage any data on your hard drive unless you place a very large and powerful magnet directly on top of the drive.   Every hard drive already contains a powerful neodymium magnet, so one moving around outside the case will not affect the data.

Which magnet coatings are there?

Table of ContentsNeodymium magnets (super magnets): Coating necessaryNickel (Ni-Cu-Ni)Gold-coating (Ni-Cu-Ni-Au)Chrome (Ni-Cu-Ni-Cr)Copper (Ni-Cu)Epoxy resin (Ni-Cu-Ni-Epoxy)Zinc (Zn)Pot magnetsSpecial coatingsFerrite magnets: No coatingNeodymium magnets (super magnets): Coating necessaryNeodymium reacts to oxygen and oxidises quickly if untreated. That's why all neodymium magnets in our shop are covered with a protective coating, which is so thin that it doesn't have any impact on the adhesive force of the magnet.We use the following coatings on our neodymium magnets:Nickel (Ni-Cu-Ni)By far the most frequently used coatingColour: shiny metallicGood price/performance ratioThickness: approx. 12 micro metresGold-coating (Ni-Cu-Ni-Au)Razor-thin coating (24k) over normal Ni-Cu-Ni coat, but with the same featuresColour: shiny metallicThickness of gold-coating without Ni-Cu-Ni: 0,05 micro metreThickness of whole coating: approx. 12 micro metresThe gold-coating rubs off easily with frequent use. It is therefore suitable for decorative purposes only, not for playing or working.Chrome (Ni-Cu-Ni-Cr)Better resistance against rubbing and pressure (that's why we use this coating for our sphere magnets)Colour: dull, grey-metallicThickness: approx. 15 micro metresCopper (Ni-Cu)Colour: shiny brown-red-gold. The colour may change over time due to oxidation (darkening, spots)!Slightly weaker rubbing and impact resistance than Ni-Cu-NiSlightly weaker corrosion resistance than als Ni-Cu-NiThickness: approx. 10 micro metresThe copper-coloured surface rubs off with frequent use (similar to gold-coated magnets) and is therefore suitable for decorative purposes only.Epoxy resin (Ni-Cu-Ni-Epoxy)(in exceptional cases also just epoxy)Colour: blackalmost 100% non-corrosive, as long as coating is intactnot shock-resistant (crumbles quickly)Thickness: approx. 10 micrometreEven the smallest, not visible to the eye, damages of the coating will cause damage to the magnet in the long term when exposed to moisture.Zinc (Zn)Colour: matt grey/blueishonly zinc without Ni-Cu-Nimore susceptible to corrosion than Ni-Cu-Nican leave black marksThickness: approx. 4 micrometresPot magnetsIf not noted otherwise, we use neodymium magnets with a Ni-Cu-Ni coating for our pot magnets. The term "coating" in the article description of pot magnets refers to the steel pot around the magnet. In most cases it is nickel (Ni); for the pot magnets that are painted white it is nickel with additional powder coating.Special coatingsThere is a variety of other coatings for neodymium magnets that we do not (or only sporadically) offer in our standard assortment.Without coatingNaked magnet material, black/greyMagnets oxidise and corrode quickly when they come in contact with oxygen and waterMagnets need to be covered air- and watertight quicklyWe do not recommend having uncoated magnets manufactured.Silver (Ni-Cu-Ni-Ag)Shiny silverRazor-thin coating over normal Ni-Cu-Ni coating, hence the same attributesDifference purely visualMaterial: Sterling SilverApprox. 12 micrometres thickTeflonGrey/anthraciteOnly teflon without Ni-Cu-NiNearly waterproofVery rub-resistant12-25 micrometres thickFerrite magnets: No coatingIn theory, you could put various coats on ferrite magnets, but that is technically complex and expensive. The price for the coating would be greater than the price for the whole magnet.Since ferrite magnets are weather-resistant even without protection, an additional coating is not necessary. Our ferrite magnets are therefore uncoated.

Can a magnet that has lost its magnetism be re-magnetized?

Provided that the material has not been damaged by extreme heat, most magnets can be re-magnetized back to their original strength.

Can I make a magnet that I already have stronger?

Once a magnet is fully magnetized, it's "saturated" and cannot be made any stronger. In that sense, magnets are like buckets of water: once they are full, they can't get any "fuller".

Why should I choose CINFER for my magnet needs?

There are several reasons CINFER is the right choice for you:QUALITY: CINFER is an ISO/TS 16949:2002 certified manufacturer. You can count on our highly developed quality system to see your parts or project through from design through final delivery.EXPERIENCE: CINFER's customer service and technical team has decades of experience with nearly every type of magnetic application. You can be assured that we will apply that experience to your specific needs each and every time to guarantee your complete satisfaction.TECHNICAL SUPPORT: CINFER has the technical expertise to help you through your most difficult magnetic design challenges. Our helpful and courteous staff is always available to get you the answers you need, as quickly and accurately as possible.VERSATILITY: No other magnet company can offer customers what cinfer can A unique combination of TS certified, domestic magnet manufacturing capability, including on-site magnetization, fabrication, design and analysis - as well as high quality off-shore sourcing options which provide our clients the best, most cost-effective options no matter what the requirements.

How are magnets made?

Magnets are made using the following methods:- Pressing and Sintering- Extruding- Injection Molding- Calendering- Casting- Compression Bonding