Eastin Weight Tools is a great addon for speeding up manual weighting. Sometimes Blender’s automatic weighing system doesn’t get it quite right and you just want to do it yourself instead of tinkering with it or when weight painting is too imprecise. In comes Weight Tools. With some simple but great features, you can quickly get your model weighted just the way you want!
Parallel Weight Gradient - Easily graduate from one weight to another over multiple edge loops.
Quick Weights - Easily assign common weights.
Copy and Paste - Copy and Paste Weights from one group to another. Multiple ways to paste (replace, invert, add, average, subtract, normalize, and weighted normalize)
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