We have this heavy-duty spiral binding machine. Compared to other brands, it can handle more sheets and offers better quality. We bought it only about a year ago, and it is still in very good condition. We would have used it for less than a month only, but due to lack of time, we dropped this business.

In this machine, you can adjust the paper alignment and also hold and tighten the spiral spring directly in the machine itself. If you search this model on YouTube, you can find full demonstrations and usage videos.