3ds max skinning fingers problem - vertexes are moved away where bone is not located

TripleB

video :
https://www.youtube.com/watch?v=gOoyXOEAnoU&feature=youtu.be

Using male biped, started with structure set to use knuckles but then I have changed it to normal hands. I have weighted whole fingers vertexes to hand bone instead of knuckles so I was able to place the fingers bones to right positions.
All this was done. But when I began with weighting vertexes of fingers to knuckles, the problem has emerged.
Adding weight to knuckle moves the vetexes away beyond fingertips.And this is happening even without playing any animation, in bibeds default T-pose.

I was even unable to find any case of this happening to anyone else on internet.

TripleB

Solution found: remove problematic bones in skin modifier and add them back. this will reset the wiegts and also fix this problem.

Mark Dygert

It looks like skin was applied to a mesh that had a problematic transform matrix history. You should ALWAYS reset the transform matrix to zero before applying skin. Command Panel > Utilities tab (hammer) > reset xform > reset selected > Collapse stack > Apply skin.

I suspect the object probably has a scale value that isn't 100 and scale is something that is transferred down the hierarchy. It normally causes problems like that where verts fly away as bones rotate. It is fairly common but a lot of people don't ever run into it because most tutorials tell people to reset the transform matrix.

If you right click the scale tool, you'll be able to check the scale value of your mesh, if its not 100 you should:
- Return your skeleton to the bind pose.
- Copy your mesh, reset xform, collapse the stack.
- Apply the skin wrap modifier and target the original mesh.
- Deform the mesh and tweak the skinwrap settings to get a tight match.
- Convert to skin, delete the skinwrap modifier and get rid of the old mesh.

This trick will save you a lot of work, you can use it anytime you need to change the topology or edit the mesh.

And... next time reset xform before skinning, it will save you a world of trouble later on. Even with your own meshes but especially with meshes from other people always assume its dirty and needs to be cleaned before progressing. You'll run into half a dozen of these types of problems your first few projects and you'll build up a checklist