Print it from Petg or something strong and flexible.
One of stl. files is designed without thread [Embroidery_frame_1(without_thread)]. It is designed with just hole so you can put there thread inserd a use it with standart bolt. This version is much stronger. If you want to start it using immediatly after printing, there is also stl. files for you. Specialy main part with thread (Embroidery_frame_1) and bolt (Embroidery_frame_3) which should match with the main part. Central part (Embroidery_frame_2) is universal.
Last photo is layout of stl. files in Gcode.
The author marked this model as their own original creation.