Summary

I modify the neck of original modell. So I made a hole in the body and in the head to simple pen spring.
Spring size: Ø5mmx30mm

This is how the head moves:
https://www.facebook.com/reel/1107540676971485

Print Settings

Printer Brand:

Creality

                                            <p class="detail-setting printer"><strong>Printer: </strong>                     <div><p>K1</p></div></p>                                                                                <p class="detail-setting rafts"><strong>Rafts: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting supports"><strong>Supports: </strong>                     <div><p>Yes</p></div></p>                                                                                <p class="detail-setting resolution"><strong>Resolution: </strong>                     <div><p>0,2mm</p></div></p>                                                                                <p class="detail-setting infill"><strong>Infill: </strong>                     <div><p>20%</p></div></p>                                                    <strong>Filament:</strong> any any                any                    <br>                        <p class="detail-setting notes"><strong>Notes: </strong>                    </p><div><p>Tree support recommended!</p></div>

Vault Boy - Fallout - spring neck - Bobble head