# How to repair the deformation made by armature

I am trying to rig the back legs of an animal, but the armature deforms it's knees and upper legs weirdly. This is the position in which it was modeled:

When I wanted to rotate the lower or upper leg, it turned out like this:

How can I fix it? (I have already tried reassigning, but maybe the wrong way)

Thanks for help.

• First off, and I can't tell if you did, you should always have the limbs fully extended when weight painting the rest pose. Secondly, you need to make sure you are using less than full weights on overlapping vertices. It looks like you have no transition space. You can do this by changing the strength of your weigh paint brush in the T menu. Let me know if you think this is your issue so I can add a detailed answer. – VRM Mar 20 '15 at 10:56
• I didn't yuse weight painting at all, although i knew that it's usualy used. This is my first rig, so I assigned vertex groups only in edit mode by selcting all the faces I wanted to deform and assignign them to the bone. – aky-her Mar 20 '15 at 11:50
• Well at least we know what the problem s now. :P – Scalia Mar 20 '15 at 15:31
• @aky-her That is what your issue is then, when you use vertex groups, all the vertices have a value of one or zero. You need to paint the fading parts in between that are affected by both bones – VRM Mar 20 '15 at 15:31
• When adding items to a vertex group, the default weight is 1.0. The weight value is a floating point number that's clamped between 0.0 and 1.0. There's a slider for adjust it to the value you want. Besides, even paint mode is going to use vertex groups. – Francisco Chavez-Tejeda Mar 20 '15 at 19:45