This is a simple 15-hook repairing machine. It is assembled by four M2 bolts. You need to bend 15 standard paper clips to make hooks and cut off the excess parts.

The bending clamp is designed to help you achieve more consistent bends. You should start bending all the hooks from the hook end, so that you can get the same hook length repeatedly. I changed my method a bit, but as a result, the length of several hooks was inconsistent, which made it a bit difficult to use in practice.

There are many tutorial videos about sewing machines on YouTube. They all make it look so simple... If you see my example, you'll know I need to practice more. I should probably start with a pair of socks that have less elasticity.