That's usually because you haven't done the steps properly in Blender.

In Blender make sure you attach the clothing to the base bone.  When you do this press Ctrl-P and select "With Empty Groups".  Now select the Base_Body (with Object Select) and, holding down the shift key, select the clothing item.  Switch to Weight Paint mode and do Transfer Weights, and change the advanced options "Source Layer" to "By Name".  Then export with Armature bones turned off and all should be well.

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

If anyone else gets stuck at this step make sure you weight map your cloth and use a name as source for weight map inside blender.

Follow this tut and it will work -






CTA5, Iclone 7, 3D Exchange Pro, Character Creator 3, Popcornfx plugin, Zbrush, Blender, Vue 2014, Adobe cc suite, Spriter
Homebuild Workstation (Pretty old now but still working great) Win 10, Intel i7 950, 24 GB RAM DDR3, Gigabyte x58a-ud7 motherboard, AMD R9 390 sapphire 8GB VRAM.
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Yes, I followed the above tut and got it done. Rampa's tut was missing the weight map point.




CTA5, Iclone 7, 3D Exchange Pro, Character Creator 3, Popcornfx plugin, Zbrush, Blender, Vue 2014, Adobe cc suite, Spriter
Homebuild Workstation (Pretty old now but still working great) Win 10, Intel i7 950, 24 GB RAM DDR3, Gigabyte x58a-ud7 motherboard, AMD R9 390 sapphire 8GB VRAM.
Official Website  Reallusion Store  

There's one more sort of critical step -- the clothing will work, but not as well.  You need to also smooth out the vertex group weights on the clothing, or it won't deform well.

I showed this in one of my tutorials (where I also wrote a Python routine that does this): however, I've since learned a MUCH easier (well, faster) way of doing this.  Just use the Smooth tool in the Weight tools options, and all will be well (I'll be creating a video tutorial about this either tonight or tomorrow).

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

There's one more sort of critical step -- the clothing will work, but not as well.  You need to also smooth out the vertex group weights on the clothing, or it won't deform well.

I showed this in one of my tutorials (where I also wrote a Python routine that does this): however, I've since learned a MUCH easier (well, faster) way of doing this.  Just use the Smooth tool in the Weight tools options, and all will be well (I'll be creating a video tutorial about this either tonight or tomorrow).

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

Because there are two materials on my hat iclone is requesting a weight map for enabling physics.

How to export weight maps for two materials separately?

CTA5, Iclone 7, 3D Exchange Pro, Character Creator 3, Popcornfx plugin, Zbrush, Blender, Vue 2014, Adobe cc suite, Spriter
Homebuild Workstation (Pretty old now but still working great) Win 10, Intel i7 950, 24 GB RAM DDR3, Gigabyte x58a-ud7 motherboard, AMD R9 390 sapphire 8GB VRAM.
Official Website  Reallusion Store  

This can range from stupidly simple to impossible, depending on how the hat is mapped.

For example, if you have a coat with buttons (so that the buttons are mapped separately) you can't do this -- there's no way you can apply cloth physics to both the coat and the buttons properly (so the answer is to remap it).  If, though, you just need the edges of the hat (which is normally the case) to have physics you don't even need to worry about the rest of the hat.

So I guess I'd have to see the hat and the mapping to know for sure.  Easiest way to play around, though, is to use a program like 3D Coat and create your map interactively (see my tutorials).

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

Well Iclone is showing me this error. What kind of greyscale map does It require? 3D coat is way expensive, I will prefer to buy substance painter rather than 3D coat for texturing.




CTA5, Iclone 7, 3D Exchange Pro, Character Creator 3, Popcornfx plugin, Zbrush, Blender, Vue 2014, Adobe cc suite, Spriter
Homebuild Workstation (Pretty old now but still working great) Win 10, Intel i7 950, 24 GB RAM DDR3, Gigabyte x58a-ud7 motherboard, AMD R9 390 sapphire 8GB VRAM.
Official Website  Reallusion Store  

Here is the UV mapping in blender




CTA5, Iclone 7, 3D Exchange Pro, Character Creator 3, Popcornfx plugin, Zbrush, Blender, Vue 2014, Adobe cc suite, Spriter
Homebuild Workstation (Pretty old now but still working great) Win 10, Intel i7 950, 24 GB RAM DDR3, Gigabyte x58a-ud7 motherboard, AMD R9 390 sapphire 8GB VRAM.
Official Website  Reallusion Store  

3D Coat expensive?  You can buy the student version (all you need) for less than $100.  And it's WAY better than SP (for one thing it will create UV maps easily, and very, very good ones, much better than you can get anywhere.  SP can't create UV maps at all).

And that may very well be what you need to do here.  Without having the hat myself I can't really say.

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley