Purchasing neodymium arc magnet should be more careful than the block magnet or the disc magnet. Because they very special, and too many factors need to confirm. In another word, the arc magnet is the custom product. No manufacturer will produce them in advance and waiting for your purchasing. If you are careless, it is very easy to lost money and waste time. So lots of customers ask Osenc Magnet Company to write some post, likes the topic about what factors should be noted in the neodymium arc magnet purchasing. So now, we would like to about this topic.
So let us introduce you the 5 Tips should be noted.
- Preparation period Should be Long
If you want to purchase the arc magnet, you should start this work as soon as possible. Because you will need a sample before you place the order. So we can calculate the time. In normal, the factory needs 14 days to 18 days to produce the sample. (If you want the high-grade magnet, factory need check the material in the market.) And then factory send the sample to you, it takes extra 4-6days. And you need 1 or 2 days to check the quality. And then pay them and ask the start their work. (It will take 3-5 days, as you know TT takes 2 or 3 days. The factory will do nothing before they get the deposit. If you or the factory makes anything wrong in the payment information, it will take extra 7-9days. ) Factory start they work when they got the deposit. The Mass production will take 18-21days.
So how many days do we need? Is there anyone have any idea?
If I am right，and everything goes well, no any mistake, the leading time of the Neodymium arc magnet is 40 days. If there anything goes wrong,60 days is possible. But as you know, God will not let everything goes well. Lots of things might happen. So 40 days must be not enough. Make the preparation period long enough will good for your work.
- Draft is important
Even you have enough preparation period, but you still save the time. And push the project finish as soon as possible. The secret is the draft. Make sure the information was written in the Draft. And what information must be shown?
Arc Degree, Arc Length, Height, Width, Thickness Inner Diameter, Outer Diameter, Plating, Grade, Tolerance
For example, the like this draft, it shows all information:
The arc degree: 55 degrees,
The length: 27mm(by the way, all of the drafts we use mm, not the cm)
Thickness : 2.2±0.05
Inner Diameter: 26.2mm
Grade N50M ( It means the magnet will be working well if the temperature under 100 Celsius degree. If you are not sure what grade to you need, you can tell the factory the operating temperature range. But please make sure the temperature you mark is Celsius Degree, not Fahrenheit Degree. Because Chinese magnet manufacturer use Celsius Degree.)
As you see the width is 3±0.05mm and thickness is 2.2±0.05mm. But what does the “±” mean?
That is the logo of tolerance. So if the width is 3.05mm or 2.95mm are acceptable. If your product is high technology, your tolerance must be smaller. And in this business, tolerance is different. Different shape, different tolerance. Like the disc magnet, the standard tolerance is ±0.05mm, but the square magnet, the length, and width are ±0.1mm, and thickness is ±0.05mm. And if you have special requirement, the disc tolerance can be 0.02mm, and the square, the length and width can be ±0.05mm, thickness ±0.03mm. As we know some manufacturer in the west, the tolerance can be ±0.01mm.
But as the tolerance is smaller, the cost will be higher. For most of the people, the standard tolerance will meet their requirement.
About the draft, as we saw that, there no temperature was written. But all of us know that the magnet can be working well if the operating temperature below 100 Degree. Because the grade was N50M. M means the magnet working well if the temperature is 100 Celsius or smaller than 100 Celsius. About the relationship of temperature and grade, you can check below form
*means the number, likes N*M, can be N35M, N38M, N40M, N42M, N45M, N48M, N50M, N52M. More information, you can visit the Neodymium magnet grade
- The quantity of S, N Pole
It looks like a very foolish question. But unfortunate, it always happens. Most of the time that happens when one of them (the seller and the buyer) is an apprentice. And the magnets are used for rotating equipment. The quantity of magnet should be plural. Like 12, 24, 26. Because the same magnetic field always pushes away something with a similar magnetic field. And the two different magnetic field will attract each other.
So if you told to the seller the quantity, you should make sure that they understand what you mean.
Likes that “we want 2400 pcs magnet, and here is the draft.（You just sent the seller picture A）and we use the magnet for rotating equipment ”. So are you mean you want 2400 pcs magnet, All of them are A magnet, and no B magnet? Or you mean you want 2400 set magnet. A magnet 2400pcs ,and B magnet 2400 pcs? If seller and buyer, both of them are new in this business. 2400pcs A magnet will be produced. But 2400 pcs are worthless if there no 2400 pcs B magnet.
- Magnetization Direction
Magnetization direction is a very important factor. If you make it wrong the magnets are worthless too. But As the arc is special shape, so there 4 type magnetization direction: diametrical direction, the width direction, thickness direction.
Different magnetization direction makes different direction has big power. So we should pay attention to that.
All factory we are talking about is very important. It helps us save time and save money. So we should remind the engineer and supplier to recheck the information are correct.