16mm scale garden railway buffer

A buffer for 16mm scale garden railway loco's and rolling stock. Use a 3mm bolt and just forcefully wind it in, it will create it's own thread. I did try using a tap, but it leaves it open to stripping the thread. Picture shows a buffer straight off the printer but before an extra hole was made in it for the coupling pin, as well as the finished buffer on a loco. Suggest using 100% infill due to it's intended purpose and suggest using support everywhere.

Obviously do not use on a steam powered loco, it will just melt, lol :)