I'm restoring another old bike of mine (20 y.o). Want to repaint the bike, but I need to remove all the parts. Trying to remove the old rusty fork but have no idea how to do it. I tried to remove the hex nut with wrench, but it didn't even move at all. Trying to hit it with rubber mallet, but still not moving at all.
You first have to remove the quill stem. To remove you undo the bolt from the top (blue arrow), and then you will probably need to tap it lightly with a hammer to push the bung nut out the bottom so it's loose enough to remove.
Once you remove the stem, you need to remove the headset lock nut (red arrow). Once this is removed, you can remove the headset nut/race (yellow arrow).
Watch out for the bearings inside the headset, they may be in a cage, they may be loose, or they may be in a worn out cage that doesn't hold them properly any more.