Flux LoRA Merger — Custom Node for ComfyUI

A custom ComfyUI node to merge up to 4 LoRA models into a Flux.1-Dev UNet

⚠️ If you experience VRAM issues (OOM) when saving, try using the sequential strategy instead of additive or average. It avoids direct weight modifications and makes saving more memory-efficient.

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✨ Features

• ✅ Merge up to 4 LoRA models
• ✅ Compatible with UNet models in FP8 / FP16 / FP32
• ✅ Three fusion strategies:
  • additive: weighted sum of LoRA deltas
  • average: average of LoRA deltas
  • sequential: apply one after another
• ✅ Option to save the final merged model in .safetensors

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📥 Inputs

| Parameter | Type | Description | |------------------|----------|-------------| | unet_model | MODEL | The base UNet model to apply LoRAs to | | merge_strategy | CHOICE | "additive", "average", or "sequential" | | enable_loraX | BOOLEAN| Whether to enable the corresponding LoRA | | loraX | STRING | Filename of the LoRA (from your loras/ folder) | | loraX_weight | FLOAT | Weight multiplier for the LoRA | | save_model | BOOLEAN| Save the merged model to output/ | | save_filename | STRING | Custom name for the saved .safetensors file |

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📤 Outputs

| Output | Type | Description | |------------------|----------|-------------| | model | MODEL | The merged UNet model |