Flux 1 on ComfyUI on Apple Silicon Mac OS

In the previous post I showed how to set up ComfyUI so it is Flux 1 ready. The main thing to be aware of and get right is to make sure you are running the Nightly version of PyTorch. So if you already have ComfyUI running on your Mac then you should make sure to get that sorted before attempting to follow this guide.

Downloads

There is no getting away from the fact you need to do some sizeable downloads. Here are the ones I would recommend you first work with to get going. There are other options which are compatible, but the fp8 and fp16 versions of Flux 1 Schnell and Dev generate MPS errors, so here’s a safe way of avoiding those issues.

Grab these four files and download them to their appropriate ComfyUI folder:

Flux 1 DEV Q4 GGUF

This is a quantised version of the full Flux 1 Dev model, which will run on a Mac.

• Link: https://civitai.com/models/647237?modelVersionId=725532
• Version: 4.1
• File Size: 6.73GB
• Destination: Users/[usnername]/ComfyUI/Models/unet

T5XXL FP16

This is one of the two clips (which are text encoders) you will need to get the model to function

• Link: https://huggingface.co/comfyanonymous/flux_text_encoders/tree/main
• Version: t5xxl_fp16.safetensors
• File Size: 9.79GB
• Destination: Users/[usnername]/ComfyUI/Models/clip

Clip L

• Link: https://huggingface.co/comfyanonymous/flux_text_encoders/tree/main
• Version: clip_l.safetensors
• File Size: 246MB
• Destination: Users/[usnername]/ComfyUI/Models/clip

VAE

• Link: https://huggingface.co/black-forest-labs/FLUX.1-dev/tree/main/vae
• Version: diffusion_pytorch_model.safetensors
• File Size: 168MB

So that little lot will take you a fair few hours to download. From my experience I’d suggest you download the large files one at a time as having two large downloads running at the same time can create a bit of a struggle for residential broadband.

Custom Nodes in ComfyUI

Whilst these files are downloading you can start to prepare your ComfyUI installation as there are some custom nodes which you will require to have installed ready to get Flux 1 up and running.

Assuming you have ComfyUI Manager installed, you can go to the Custom Nodes Manager section and install the following:

• ComfyUI-essentials
• ComfyUI-GGUF

These combine to allow you to open the model and have a simplified workflow, so whilst the ComfyUI-essentials is optional, it makes for a better user experience. Here’s what it looks like in my ComfyUI Manager (with another custom node inbetween):

Decompress zip Files

Assuming all of the downloads have occured you should check the folders and if any of the files are downloaded as zip file, you will need to decompress / expand these.

At the time of writing (Feb 25) you should only need to expand the “Flux 1 DEV Q4 GGUF” downloaded to the unet folder. Though it can’t harm to check the others out.

Flux 1 ComfyUI Workflow

Right, so most of the hard work is done now, just need a workflow. I’m making my workflow available to download here:

https://www.head4space.com/assets/FLUX1-GGUF.json

You can also view the workflow in this screen shot, so if you wish to replicate the components then you can – although it can be tricky to understand how the different aspects are connected.

Refereces and Further Research

This post would not have been possible without this awesome piece on getting Flux 1 working on an Apple Mac: https://medium.com/@tchpnk/flux-comfyui-on-apple-silicon-with-hardware-acceleration

It took me a little while learning ComfyUI to be able to understand some of the context and the more complex aspects of the post, but it’s well worth diving into as some of the work the writer has done goes into more detail about some of the tests he has done.

My previous post about getting ComfyUI setup on your Mac:

Install ComfyUI on Mac OS for Flux 1