# FOrcaSlicer - Flexible OrcaSlicer | Finer Controls for Snapmaker U1 With Mixed Nozzle Sizes and Color Patch Mode **URL:** \ **Category:** U1 Toolchanger\ **Created:** [July 18, 2026, 1:52pm UTC](https://forum.snapmaker.com/t/forcaslicer-flexible-orcaslicer-finer-controls-for-snapmaker-u1-with-mixed-nozzle-sizes-and-color-patch-mode/42560 "2026-07-18T13:52:17Z")\ **Posts on this page:** 1\ **Showing post:** 1
**Author:** ![jiyang1018](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.snapmaker.com/jiyang1018/32/34484_2.png) [@jiyang1018](https://forum.snapmaker.com/u/jiyang1018)\ **Post date:** [July 18, 2026, 1:52pm UTC](https://forum.snapmaker.com/t/forcaslicer-flexible-orcaslicer-finer-controls-for-snapmaker-u1-with-mixed-nozzle-sizes-and-color-patch-mode/42560/1 "2026-07-18T13:52:17Z")
**TL;DR:** FOrcaSlicer (FOS) is a fork of Snapmaker OrcaSlicer for the Snapmaker U1. The U1 has four independent print heads, and FOS makes each one capable of carrying a **different nozzle diameter** and doing a **different job** - a fine nozzle on the visible surface, a coarse one on everything behind it, and painted color applied as a thin shell instead of a solid block of filament. Snapmaker Orca is a great slicer to build on; FOS just leans into the U1’s four-head hardware in a way stock doesn’t yet. Everything below is verified in G-code. It’s still early, so feedback is very welcome. ## Launch demo A short walkthrough of what FOrcaSlicer does differently from stock Snapmaker OrcaSlicer, across three areas: **mixed nozzle sizes** , **splitting the outer and inner wall onto different heads** , and **Color Patch mode**. [![gallery image 1](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/d/f/df54b303828fd85e5403854ab4474397d5c22d19.jpeg)](https://youtu.be/5z-unU9aujo) ## The Idea: Four Heads, Four Jobs Most multi-material slicing treats extra heads as a _color_ feature - same nozzle, different filament. But the U1’s heads are independent hardware, so they can carry different nozzle sizes. Once you accept that, the four heads become a fabrication strategy: spend precision where it’s visible, and speed where it isn’t. ## 1. Outer Wall / Inner Wall Split Stock treats “walls” as a single setting. FOS splits them into two independently assignable features: - **Outer wall (OW)** on a small nozzle (e.g. 0.2 mm) - the surface you actually see and touch. - **Inner wall (IW) + infill** on a larger nozzle (e.g. 0.4-0.6 mm) - nobody sees it. - **Solid infill** on a larger nozzle (e.g. 0.4-0.8 mm) - it prints faster on flat top and bottom faces. A set of gears printed with a 0.2 mm outer wall and a 0.4-0.6 mm interior has the **same tooth profile** as an all-0.2 mm print, but finishes in about 5 hours instead of 8.5 - even with a wipe tower running. ![gallery image 1](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/e/6/e68dfcd1fbd76e82fd14a899f379b21057e3b9fc.jpeg) And it’s not only speed. You can put a **different material** on each: a low-friction nylon ¶ tooth flank over a stiff carbon-fiber-nylon (PA-CF) core, at the same time. One nozzle can’t do that. ## 2. Per-nozzle Settings Each nozzle prints at its own **line width and speed** , and support and the prime tower are sized to the nozzle that actually prints them (no more a 0.2 mm tip being told to lay a 1.0 mm tower line). Each nozzle can also carry its own process preset. ![gallery image 2](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/b/d/bd9f7b29d868421ca58865997b1ecced83311051.jpeg) ## 3. Color Patch: Color As a Surface, Not a Volume When you paint a region in most slicers, the whole solid volume beneath it becomes that color - buried filament you never see. **Color Patch** applies the painted color as a _shell_ of a few perimeter loops and keeps the interior as base material. Same look, a fraction of the colored filament. The fun part: shell and core can be different materials. A soft TPU grip becomes a shell that mechanically **wraps** a rigid PETG core - TPU won’t chemically bond to PETG, so a side-by-side paint would delaminate, but a wrap holds. ![gallery image 3](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/6/e/6e516e1fa7004c9f391fa0b0e73824d0943fd5d5.jpeg) Translucent shells also give real see-through effects (think a legging over a skin-tone leg). ![gallery image 4](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/6/5/65cbd403a57fa5057db8136f13e0fc62a865bbef.jpeg) ## Being Honest About the Limits - **Layer height is still shared** , bounded by the smallest nozzle in use - so a 0.2 mm outer wall pins the whole print to a fine layer height. Per-nozzle layer height is the big in-progress feature. - **The U1 firmware doesn’t support mixed-nozzle printing from the touchscreen yet** - you send the job directly from the slicer. Lifting that needs a Snapmaker firmware update, which is out of my hands. - **Windows only, Snapmaker U1 only.** I do not have another multi-toolhead printer to test with, and I am not a programmer nor software engineer. Windows and Snapmaker U1 are the things I have to test with. ## A more detailed Wiki is also available at: [https://github.com/jiyang1018/FOrcaSlicer/wiki](https://github.com/jiyang1018/FOrcaSlicer/wiki) ## How to Get It Project repo is at: [https://github.com/jiyang1018/FOrcaSlicer](https://github.com/jiyang1018/FOrcaSlicer) The latest release is at: [https://github.com/jiyang1018/FOrcaSlicer/releases](https://github.com/jiyang1018/FOrcaSlicer/releases) Dev roadmap is at: [https://github.com/jiyang1018/FOrcaSlicer-roadmap](https://github.com/jiyang1018/FOrcaSlicer-roadmap) --- _[View the full topic](https://forum.snapmaker.com/t/forcaslicer-flexible-orcaslicer-finer-controls-for-snapmaker-u1-with-mixed-nozzle-sizes-and-color-patch-mode/42560)._