# Problem with weight painting

I am new to blender and a while ago I started having a problem with weight painting on a certain part of one of my models. Variations in the weights of vertices seemed to be having no effect; they would all act as if their weight was 100%. Soon it was happening throughout all areas of all of my models.

What is going on here and how can i fix it?

• Is weight shared with any other bones? If there are no other bones with weight then the one that does have weight is contributing 100% influence. Jan 31, 2017 at 2:35

Bones affect the mesh based on their proportional weight on each vertex. The influence for each bone is calculated by dividing that bone's weight by the total weight of all bones affecting that vertex. So if the weights of all the bones add to one, then the bone influence will be the same as the weight, whcih makes things easier to reason about (the normalise function in blender will make all the bone weights sum to one).

For example if vertex 1 has the following weights:

• Bone1 : 0.5
• Bone2 : 1
• Bone3 : 0.5

Then Bone1 has an influence of 0.25 (0.5 / (0.5 + 1 + 0.5)).

In your case you only have one bone affecting the vertex so the influence of that bone will always be one.