Retractable Pen (PIP)

This is a fully working print in place pen with retraction mechanism by twisting the lower ring 120° to move the refill out.

Print

The test can be used to ensure to meet the 0.35mm clearance spec

• max nozzle = 0.4 (thinnest wall is 0.4) 
• internal support needs layer = 0.08 also for smooth mechanics 
  •  if you scale this up in z - increase layer height accordingly e.g. 0.08*1.25 (125%)=0.1
• use a brim or raft for stability
• no supports

post Print

• To make this working start with wiggling the ring and twist a little until the internal support breaks free.
  • Use a stick or refill from the back to move the internal slider for the first time. And twist the Ring until it fully moves and rotates 120° or ⅓ turn.
• Use a little grease or PTFE/Silicone Spray for best performance

Refill

put a 3mm in from the front - if it is too long the excess will come out at the end so you can cut it (or leave).