I really like Super_Laserkatz's lamp designs but only have E14 Sockets around.  So i have designed a Lamp adapter for a 26 mm diameter E14 socket, the type often used in DIY rock salt lamps. Example on AliExpress:

Instructions:

1. Print the adapter. Use your preferred material. After printing, remove all support structures.
2. Test the threads. Screw the nut onto the bolt, then unscrew it. Do this twice to make sure the threads fit smoothly.
3. Remove the clip (if present). If your lamp socket has a metal butterfly wire clip, take it off using force and some strong pliers.
4. Open the lamp socket. Unscrew the socket’s own threaded cap. Slide the nut all the way down the power cable.
5. Attach the mounting ring. Put the lamp socket through the printed mounting ring.
6. Insert into the lamp base. Put the socket (with the ring still on it) through the base of your lamp. Going from the bottom up.
7. Install the socket in the adapter: Put the cable through the adapter’s cable opening. Pull the cable down until the socket sits firmly inside the adapter’s flexible housing.
8. Tighten the e14 socket threaded cap (optional). Pull the nut back up the cable and tighten it from below. If your fingers are too big or it’s tricky, you can skip this step as the housing should hold the socket securely.
9. Mount the adapter. Screw the mounting ring tight to secure the adapter to the lamp base.
10. Done! Your adapter is now installed and ready to use. Install your E14 Lamp and you should be good to go.