SDXL-SGM Components Params

When you merge two SDXL checkpoints, you usually don't want every component moved by the same amount. A flat 50/50 blend often drags in the other model's weird style at full force, especially through the text encoders. This node - the SDXL-SGM Components Params node from comfy-mecha - is the fix: one slider per SDXL component, so you can merge the UNet hard and barely touch the CLIPs.

It's a "param" node, not a merge node. It doesn't merge anything on its own. What it produces is a MECHA_RECIPE - a set of per-key weights - that you feed into the weight/param/alpha input of a merge recipe node like Weighted Sum or Add Difference. Because mecha lets an alpha be a recipe instead of a scalar, the merge applies a different strength to each component. That's the whole trick.

What the sliders mean

The node exposes exactly the five components of the SDXL-SGM key layout:

• diffuser - the UNet. The part that actually draws.
• clip_l and clip_g - the two text encoders SDXL uses (CLIP-L and OpenCLIP big-G). They carry most of the "style fingerprint" of a checkpoint.
• vae - the image autoencoder. Rarely worth merging; most people set it to 0 and keep one VAE.
• scheduler - the noise schedule (alphas/betas). Usually just leave it.

A typical setup: diffuser at 1.0, clip_l and clip_g at 0.3–0.6 if you want some of the other model's prompt behavior, vae and scheduler at 0. Set something to 0 and that component isn't touched at all - the merge keeps model A's version.

How it works

Under the hood, each float becomes a literal per-key weight restricted to its component, and the five are combined into one recipe (the node builds pick_component recipes and ORs them together). The output is a plain MECHA_RECIPE - wire it into a recipe node's (delta|param|weight) input, then finish at Mecha Merger to get a usable MODEL/CLIP/VAE. If you'd rather bake the whole thing down and reuse it, route the result through the pack's Serializer to get .mecha text.

Install

Same as the rest of the pack: in ComfyUI Manager, search "mecha" and install Mecha Merge Node Pack, or manually:

cd ComfyUI/custom_nodes
git clone https://github.com/ljleb/comfy-mecha.git
pip install -r comfy-mecha/requirements.txt

Then restart ComfyUI. The pack's only real Python dependency is the sd-mecha library - no model downloads. Everything shows up under the "mecha" category.

Gotchas

The name matters more than it looks: this is the SGM node, i.e. built for SDXL checkpoints in the original Stability key layout. If your checkpoints were trained or converted with kohya-ss scripts, their keys use a different naming, and you want the SDXL-KOHYA variant instead. Plugging the wrong config into a merge is the classic way to get "no keys matched" confusion. And honestly - if you always merge everything at equal strength, this node is overhead. It earns its keep the moment you want the UNet and the text encoders moving at different speeds.