To repair the Hp-9x Topcat idler gear, Isabelle suggests the following: 

- Select a metal gear instead of cheap plastic.

- Drill the center axis to d=2,30-2,40mm.

- Insert on axis and push.

- Mount back printer on Topcat.


Isabelle's tip: you can order the metal gears described here from GHW Modellbauversand at: 

www.modellbauershop.de

Reference: 753030

You'll have to drill it anyway though...

  • The deadly broken idler gear
  • Left the broken gear, mid GHW gear, right drilled gear.
  • Left: GHW gear. Right: Final gear after drilling. Nice, eh :-)
  • The new gear fits perfectly.
  • Final gear on the printer
  • Final printer assembly after repair.