What is the reason for the hair loss of the brush

Many new customers came to consult, and the hair fell out when they just bought the brush?
1. The brush needs to drill holes and plant hair. The diameter of the holes varies according to different customers. There are 1.5-10 mm holes. First of all, there are several important factors in master's machine adjustment, which directly lead to hair loss.
Each hair bundle and eyelets must be full of holes, or they will lose hair, which is one of the reasons.
In addition, under the condition of full hole, the pulling force of each hair bundle is not enough. The pulling force of hair planting in the normal brush industry is 8kg.