Derailer post fix on Carbon frame

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#1

Hello ,
How would you fix this broken piece ?
It happened from a crush .
Any suggestions would be welcome

#2

Is that a full composite dropout with an aluminium threaded insert for the derailleur?

#3

Yes … exactly

#4

That is a bad design and was always going to end in tears. I would cut off the carbon leg and fashion up a full aluminium replaceable style hanger. Wheels manufacturing probably have something that you could modify to work. #279 or #349 from the wheels manufacturing catalogue might be able to be modified to fit.

#5

Yeah, modify an existing one that could be bonded on further up perhaps. Alternatively, if it was me, Id try and look at a few things but you’re likely to have a thicker section than it used to be. Carbon drop-outs are fine for pro bikes that can be thrown away but for every day people like us, they’re a high risk strategy!

  1. chop off the cracked bit ensuring all the damage is removed. Scarf back surrounding layers, scuff everything up too. Bond either a hacked up up mech hangar by butt joining it to the carbon. Laminate carbon over the top when finished to reinforce
  2. chop off the cracked bit ensuring all the damage is removed. Scarf back surrounding layers, scuff everything up too. Then try and fabricate a hanger where you can bond over the carbon in double shear (double lap joint) around the drop-out as much as possible.