CivArchive
    ButtSlider Butt Size Slider - MiniMax H3 - v1.0
    NSFW

    Higher Weight = bigger butt

    Lower Weight = smaller butt

    This LoRA is trained using multi-lora inversion with SVD to rerank back to 4, so it is very well targeted to just the butt-size concept. Tt can be set to weights beyond -[1,1], but extremely high weights can still cause issues.

    Description

    FAQ

    Comments (19)

    rjoxSep 8, 2026· 15 reactions
    CivitAI

    *bakes this into the checkpoint permanently at a weight of 15.0*

    ComfyTinker
    Author
    Sep 8, 2026

    You may experience eldritch horrors :D

    JellaiSep 8, 2026· 2 reactions
    CivitAI

    How did you do this? Many people told me that training sliders just doesn't work on Minimax H3. Is there new AI Toolkit code that allowed for this, or did you figure out a useful approach?

    ComfyTinker
    Author
    Sep 8, 2026· 3 reactions

    No, this uses a custom python script I put together. This does not use AI Toolkit's code, but instead uses what I call inversion training.

    ComfyTinker
    Author
    Sep 8, 2026· 2 reactions

    @GlowingGuardianGirl Depends on the concept. For butt size, I train at rank 8 and derank down to rank 4 while combining.

    gambikules858Sep 8, 2026

    if multiple characters ? one small ass other with huge ass

    makiaeveliSep 8, 2026

    @gambikules858 you could do this with anything. Literally a slider for apples to oranges if you wanted. But it may just temporally explode. The author does mention that, having to attack the A and B loras differently sometimes depending on how well they come together

    ComfyTinker
    Author
    Sep 8, 2026

    @gambikules858 This is a concept-style LoRA, so it affects the whole scene. It is not possible to only target singular subjects in a scene. You could use a Ref2V in MiniMax to do this, though.

    JellaiSep 8, 2026

    @ComfyTinker Is that custom python script anything you're willing to share? I think what you've done is amazing.

    ComfyTinker
    Author
    Sep 8, 2026· 2 reactions
    JellaiSep 8, 2026

    @ComfyTinker Okay, looking at the way this works, it looks like it can't work like AI Toolkit. You actually need two datasets, instead of training with text like Ostris's slider stuff, and you need to train two loras. So this slider lora takes twice as long to train, right?

    But by using datasets, you can train a continuum of a concept where both sides may not even exist in the model, correct? Or at least may exist in small/weak amounts.

    ComfyTinker
    Author
    Sep 8, 2026· 1 reaction

    @Jellai I have used diffusion_pipe, Ai-toolkit, and musubi tuner to generate these loras, but yes you are correct. This LoRA was not trained in 1 iteration, but instead 2 separate trainings (large butt and small butt), then the inverse SVD merge of the 2 results in a sliding LoRA.

    The super useful thing is if your datasets have very similar details (always nude, always in front of a black background, always a white woman), then they will dampen or completely cancel those out, allowing the LoRA to go beyond 1.0 strength without causing drastic issues.

    Additionally, there's the emergent behaviour of being able to produce asses that are way bigger and way smaller than my training dataset. My training dataset's asses are all actually around the size of weight:1 asses or weight:-1 asses.

    JellaiSep 8, 2026

    @ComfyTinker Great dataset tip. I'll keep that in mind.

    kenybob09431Sep 8, 2026· 1 reaction
    CivitAI

    Thanks

    tnkosmo595Sep 8, 2026· 3 reactions
    CivitAI

    Brilliant. Thank you so much. You've made H3 much better. Are there any other sliders planned? Perhaps for hips, head size, waist, or overall thinness?

    nexip48008131Sep 11, 2026
    CivitAI

    Awesome work. Will this modify a reference body from i2v or ref2v?

    ComfyTinker
    Author
    Sep 11, 2026

    With following minimax's super detailed prompting instructions for retention analysis, you could get ref2V to discard the body and regenerate, but i2v is a different story.

    mememanoverdrive558Sep 12, 2026
    CivitAI

    Good lora, i appreciate your effort for the community.

    LORA
    MiniMax H3

    Details

    Downloads
    1,502
    Platform
    CivitAI
    Platform Status
    Available
    Created
    9/8/2026
    Updated
    9/14/2026
    Deleted
    -

    Files

    ButtSlider_V1.safetensors

    Mirrors

    CivitAI (1 mirrors)