Slip harpoon tip, how to make it at home?

How to make a slip tip at home for all kinds of harpoons, because slide points cost more than 30 or more than 40 dollars, slide points that work for rubber speargun, air speargun, slingshot spears pole, pole spears and more. This stainless-steel tip is multipurpose since you can use many tips in a single fishing, and you can be used on different spear pole and all spearguns and harpoons, it is safer because it prevents vibrations when the fish is hooked. In the video you will see that I made it out of a screw and a stainless steel tube, using a drill from the bolt I made a pivot on one end and put it inside the tube under pressure with a hammer, then I soldered the union with silver and the I roughed up the rest with a file, then I made a round point, it is less penetrating but it does not deform very easily when it collides with a rock, but with the pressure in which it shoots if it penetrates it goes through the meat and is fixed. Then almost in the center I made a flat cut with the hole where the cable is going to be attached with the rope, so when the fish pulled the tip move horizontally behind the body of the fish and it is almost impossible for it to escape. I hope you like the video and find it useful