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