SENSEI Swivel Thumb shears are trouble free. We invented our unique recessed washer system that keeps the nylon bearings safe and secure unlike other brands, where they tend to wear out quickly. They have a screw that you can easily adjust with a penny or a dime. The key thing is to not let the thumb get loose, so it rotates on its own when you remove your thumb. If the thumb ring turns on its own after you take out your thumb, turn the screw slightly to the right until it stays in place but still can turn smoothly when you want it to. Beyond the thumb ring, the swivel shears SENSEI makes are high-quality tools that will last a lot longer if you take good care of them. Keeping your tension adjusted, as with all shears, is important. Here is a link to a video on Adjusting Tension. Keeping them clean and oiled is important too, and you can find out about doing that with this link. Also, when it comes time to sharpen your shears, this is when you really want to reach out to us, so we can help you with that. Call our office Monday through Friday from 9 p.m. to 5 p.m. Pacific Time regarding swivel shears maintenance. Our friendly, helpful staff will be able to take your info and send you a prepaid label so that you can send them in with tracking and insurance without leaving your salon. You will get them back within a week, and they will work and feel like new again. Letting random guys who come to the salon work on your shears will void your warranty and, in many cases, shorten the life of your shears. No license is required for sharpeners, so you really have no way to know if the person calling on you really understands what they are doing. Many will put heat into the blades by dry grinding them with a sanding disc, ruining their ability to stay sharp as long as they should. They often use too harsh of abrasives and that grind your blades away. Finally, they can put the wrong angle of edge on your shear, and then the cutting feel is destroyed and much more needs to be done to bring them back to working order. This also shortens the life of the shear. If you use the manufacturer to do your service, you can demand that they always work as they should, so that is the safest way to go.