China Neodymium And Ferrite Magnets Manufacturer & Supplier 
Magnets with holes is a common type of magnet, there are mainly 2 kinds of screw holes and straight holes, the small holes in the title generally refers to straight holes, mainly used for fixing, connecting and transmission and other applications, if the diameter of the holes is too small, it may lead to the inability to install, so there is no way to improve the problem of small holes?
Neodymium round magnets with 2mm small hole in the center
Method 1: Expand the magnet hole diameter
The hole of the magnet is the magnet manufacturer through the drilling equipment, so if the hole is a little small, you can expand the hole diameter by using a carbide or diamond drill, the processing needs low speed, use coolant, if you are not professional, it is easy to lead to magnet rupture, it is recommended to complete the process with the help of professional equipment or technicians.
Method 2: Change the magnet with the right hole diameter
If you think you have trouble reaming the hole, you can change the magnet that meets the requirements of the hole diameter, if it is the supplier's problem that leads to a small hole, it will usually be dealt with for you, if it is your own problem that leads to the wrong hole diameter, then you can only pay to have the magnet manufacturer to re-process it.
Method 3: Adjusting the fixing scheme
If the magnet cannot be directly machined or it is temporarily inconvenient to change the magnet, you can consider using it for glue fixing, or reducing the size of the shaft to fit the small hole diameter.
The above is about the magnet hole is small some solutions, I hope that such as you have to help, such as the need for customized permanent magnets with holes can contact us for you to quote.
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