Derailleur hanger #19 - I recommend Carbon fiber filament

thingiverse

Mountain bikers face a specific challenge when it comes to mounting their derailleur. The type of bracket used depends on the bike model and the manufacturer of the derailleur itself, which usually includes a hanger at purchase. A common problem encountered by enthusiasts is that rough terrain conditions can cause damage to this hanger. One simple solution to this issue is to create an alternative hanger that can be easily swapped out if the original gets damaged during a ride. This temporary fix will provide peace of mind until a metal replacement can be purchased. It's worth noting that the M4 thread is not typically included, as it can be tapped into place with a standard tap or screwdriver. However, the 1mm step M10 threading is less common and safer to have pre-drilled for added convenience.