Rigging problems - vertices not following bones

[RextheRunt]

Hi people!
I’m struggling with rigging…At first my mesh wouldn’t move at all, then I found that the parent type for the armature was blank. I set it to Armature. Then the mesh started to move with it.
However, a lot of vertices are left behind - it causes the mesh to stretch like crazy.
I know I’ve made a lot of errors in my modelling, but perhaps there’s an easy explanation for what’s happening here?

Thanks!

[NP5]

It looks like many verts have not been added to any bone.
You could clear all the parenting and redo the parenting Sounds like something was wrong. Just clear all parents and re parent with automatic weights as usual.

Otherwise it is probably down to using weight painting to assign those non moving verts to the bone required.

[RextheRunt]

Thanks for your response. I’ve tried clearing and reparenting many times - same outcome.
I’ve not done weight painting before, so I’m unsure. If I go into weight painting mode, it’s all blue, which I take to mean nothing has any weight?
Could this also happen if there is bad geometry? There are definitely some serious issues after I did the whole baking process - lots of areas are badly out of shape and in need of surgery.

[NP5]

It may well be double geometry, always worth a Merge by distance to see if it removes some.

I just do not think it looks likely. Verts are not moving at all.

Weight painting should look Red on the verts the selected bone wants to be fully in parental control of. There can be some shade variance Green to blue for verts it shares control with the next bone in the chain.

So to get there so it works.
Object mode.
Select the armature, then shift select the mesh object.
Go to Weight Painting mode.

Open the Mesh object properties tab panel, (green triangle)
Open the Vertex Groups dropdown. Here you can select the bone to work on the verts it has power over.
Select vert selection, (may be used for face but unlikely).
Set view to Wireframe And X-ray.
Select the paint brush tool top of the T left hand toolbar.
Along the top you set the weight you want to paint so 1 is full control. 0 is no control. Radius is just brush size.

Now the odd bit. If no vert is selected nothing paints, nothing works.
So you can press A and select all, now the painting brush tool works.

Or Select verts you want to affect and leave the rest unselected and they never get accidental changes!

I find pressing C for circle select a handy route. Hold middle mouse button for deselect. Right click to get out of circle select mode.

Now just set the weight you want and the strength and paint as wanted. If strength is low you can paint over several times to get up to the weight set. Once it is working it is really just practice, setting the weights and strengths. Painting fully off and fully on is pretty easy. But the connections need subtle sharing of control.

[RextheRunt]

Thanks so much for your detailed reply, I really appreciate the time you took to address my issues.

I decided that to learn about rigging it would be better to start with a simpler mesh, one without issues. So I made an antelope following Grant’s low poly modelling giraffe tutorial.

Your guidance has helped me understand that when going into weight paint mode, only the selected vertices will show the weight painting…I stupidly thought that I would see all the shading and was confused to see only the bum with a greenish colour, thinking no weighting was happening.

I made sure my mirror modifier was applied before adding a horse armature with automatic weights. I repositioned the bones and when I went into pose mode, it worked, EXCEPT…The front legs were mirrored - i.e. both legs move with the same bones. I checked that mirroring is off on the armature.
I wonder if there was something in my model that caused this? Or perhaps it’s normal to have to adjust an automatically applied rig?

I followed your instructions and have sorted out most of the issues. The front legs were both weighted equally, so I sorted these out. Some areas seem to be perfectly assigned (like the ears) but won’t move. Others have random vertices moving, so I’ll persevere and try to get it all working properly.

Thanks again for your help!