# Discrepancy between socket rotation and mesh attached to socket rotation

I have a socket on the right hand which on the first image seems to be slightly rotated to the left.

I have a pistol without rotation attached to that socket which is significantly rotated to the right in the second image.

They are slightly rotated differently in all other axes too.

This also happens on all new sockets that i add

Hi gidcheen -

Thank you for your report. I have assigned a Support Technician to look into this issue. They will be contacting you shortly.

In the meantime, please be sure to review our suggestions for how to report a bug, and feel free to edit your post if you have additional information to provide:

Thank You Again -

Eric Ketchum

Hey gidcheen,

So when creating sockets for you joints the socket inherits the tangent space information from how you oriented your skeleton.

So say you modeled your character in a t-pose where Y is up in the joint that controls your right wrist. Now you import that skeletal mesh into UE4 and you pot that character in a pose that has both of it’s hands by it’s side in a relaxed pose. Now, Y is no longer up. The Y instead is facing out from the character.

The same thing applies to what you are experiencing. Looking at the characters right hand I can see that his wrist is facing slightly inward. In turn the socket is going to inherit it’s values from the joint you attached it to and then the gun will also inherit down the chain it’s information from the socket.

In order to fix this you will have to orient the socket to match the orientation of the bone. You are able to get away with this because of the hierarchy from Jont > Socket > Gun.

Thanks,

I still do not understand why the pistols x and the sockets x axis do not allign.

i would understand it if it was rotated by 90 or 180 degree but i dont understand that small difference.

I made the hand face directly forward now and the issue is gone.

Do they interpret the axis differently? so the sockets offset in the y axis gets applied to the x or something like that because the the fbx is in a y up and unreal in a z up system?

I found the issue:

The pistol mesh was rotated even though my screenshot shows otherwise.

The engine seemed to not have updated the rotation in the textboxes.

I found the issue:

The pistol mesh was rotated even though my screenshot shows otherwise.

The engine seemed to not have updated the rotation in the textboxes.

That should not matter on the x-axis. As long as they return the same value then the x should align as expected.

Some troubleshooting steps :

1.) Make sure you freeze transforms before exporting your mesh, so the rig isn’t inheriting any information form your model before entering UE4

2.) Align your hand straight forward so the socket isn’t inheriting any rotation from the X that is not 0.

3.) Set the Socket to 0 so that the hand and gun act in the way you would expect. Then move the joint only. Everything else will move because of the parenting to that joint.

4.) If you have something like Ik’s in your rig that may play into this.

Let me know what happens,

Ah,

It is true that there will be some discrepancies between which axis is up. You will have adjust different values to reflect what you want in that area. You can always change which axis is up in your modeling program before export.