Hide bone by name = crash


Here are the bones of my weapon skeletal mesh:

I want to hide the weapon attachments the first time I equip it and unhide them on demand, so I have added a “hide bone by name” at the end of my blueprint (after attaching the weapon to my character) and put a bone name for testing.

Once I equip the weapon, the engine crash. I tried every “Phys body option” but it still crash.

I would like an answer from Epic. It’s a bug or am I missing something?

Hey Haoris,

I’ve attempted to reproduce your issue by hiding one of the bones on the default FP_Gun from the FirstPersonTemplate, but the same crash is not reproducing.

Could you please provide the following:

  • A detailed list of steps we can follow to reproduce the issue in a clean project
  • The logs from your project’s Saved->Logs folder after the crash occurs
  • Your Machine ID from the crash reporter window if you’re getting one, and ensure to hit Send & Close on the report.


I think I know where the problem is. If I add my skeletal mesh in the world and use the “Hide bone by name” node in the level blueprint, it works and don’t crash.
But I use a skeletal mesh component as a variable in a function of my blueprint and use this variable as the target of the “hide bone by name” node. Once the function is executed, the engine crash. Of course the variable is set before hiding this bone.

link text


My project is complex, I will look for how to reproduce the crash with a simple project.

Ok, I got it, try this blueprint in a new blank project:

The bone name is the name of one of my skeletal mesh bones as you can see on first post.

Edit: I tried it with the FirstPerson blueprint, it crash too:

Hey Haoris,

I have been able to reproduce your crash, and have entered a bug report: Unreal Engine Issues and Bug Tracker (UE-37467)

Thank you for your report.

Have a great day

This is still happening in 4.21!

it is still happening in 4.22 -At “Event Begin Play” I do try to hide head bone just for FPS purpose.