# Fatal bug in slicing **URL:** \ **Category:** Snapmaker Orca\ **Tags:** Bug-report\ **Created:** [October 17, 2026, 5:28am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677 "2026-10-17T05:28:59Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![dbvanhorn](https://avatars.discourse-cdn.com/v4/letter/d/58956e/32.png) [@dbvanhorn](https://forum.snapmaker.com/u/dbvanhorn)\ **Post date:** [October 17, 2026, 5:28am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/1 "2026-10-17T05:28:59Z")
```auto **Title:** Slicing crashes immediately on a multi-object plate when E-cores are in the CPU affinity mask (i9-13900K) — works with P-cores only ## Environment | | | |---|---| | Snapmaker Orca | 2.4.0, build 01.10.01.50 | | Orca Web | flutter 2.3.38, build 20260915154633 | | Profile | 02.03.03.03 | | OS | Windows 11 build 26300 (10.0.26300), 64-bit | | CPU | Intel Core i9-13900K — 8 P-cores / 16 threads + 16 E-cores = 32 logical | | Printer preset | Snapmaker U1 (0.4 nozzle) | | Process preset | 0.20mm High Quality @Snapmaker U1 (0.4 nozzle) | | Filaments | 3 slots configured | ## Summary On a plate of 9 objects totalling ~130,000 triangles, pressing Slice terminates the process in 1–2 seconds. No error dialog, no entry in the log — the process simply exits. Restricting the process's CPU affinity to the P-cores makes it slice normally and repeatably. The crash requires the E-cores to be in the mask. ## Steps to reproduce 1. Import 9 STLs onto one plate (~130k triangles total; largest single object 42,396 triangles, present twice). 2. Auto-arrange. 3. Slice. Process exits within 1–2 seconds. ## Affinity results (same plate, same session, repeatable) | Affinity mask | Logical processors | Result | |---|---|---| | default | 0–31 (16 P-core threads + 16 E-cores) | **crash in 1–2 s** | | `ffff` | 0–15 (all 8 P-cores, no E-cores) | slices normally | | `ff` | 0–7 (4 P-cores) | slices normally | Set via Task Manager → Details → Set affinity, or at launch with `cmd /c start "" /affinity ffff `. Note that 16 P-core threads at full load is a *higher* power and thermal load than the default mask, and that case succeeds. The variable is core type, not total load — which is why I'd expect a race condition in the slicing thread pool, exposed by the large timing disparity between P-cores and E-cores, rather than a resource limit. ## Ruled out - **Geometry.** Every object slices individually. Pairs and triples of them slice. A 5-object plate of trivial boxes (2,124 triangles) slices. All meshes were independently verified closed, manifold, consistently wound and free of degenerate facets before testing. - **Object count.** A different 13-object plate at ~64,000 triangles slices fine on the default affinity; this 9-object plate at ~130,000 does not. - **Prime tower.** Disabling it (Process → Global → Multimaterial) changes nothing. All objects are on extruder 1 in any case. - **Build volume and placement.** Tallest object 178 mm against 270 mm; total footprint ~26,000 mm² against 72,900 available. ## Secondary issue, probably unrelated but reproducible Every launch logs this twice: ``` [error] Slic3r::GUI::PartPlate::calc\_exclude\_triangles: Unable to create exclude triangles ```auto Traced to `system/Snapmaker/machine/fdm_toolchanger.json`, which the U1 profiles inherit from: ``` “bed\_exclude\_area”: [“0x0”] ```auto A single vertex cannot be triangulated. By comparison the A250/A350 profiles carry four-point polygons. This leaves the plate with no valid exclusion geometry and affects every U1 user. ``` ---
**Author:** ![MasterPrinter1](https://avatars.discourse-cdn.com/v4/letter/m/f0a364/32.png) [@MasterPrinter1](https://forum.snapmaker.com/u/MasterPrinter1)\ **Post date:** [October 17, 2026, 2:58pm UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/2 "2026-10-17T14:58:16Z")
the 0x0 single-vertex exclude area theory checks out, the a250/a350 profiles carry real polygons there. hopefully it’s a one-line json fix. ---
**Author:** ![dbvanhorn](https://avatars.discourse-cdn.com/v4/letter/d/58956e/32.png) [@dbvanhorn](https://forum.snapmaker.com/u/dbvanhorn)\ **Post date:** [October 17, 2026, 9:20pm UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/3 "2026-10-17T21:20:17Z")
Yup. The other one is more insidious as people will hit it and have no clue even where to begin debugging it. Setting the affinity to cores 0..15 is a practical workaround till it’s fixed. ---
**Author:** ![MasterPrinter1](https://avatars.discourse-cdn.com/v4/letter/m/f0a364/32.png) [@MasterPrinter1](https://forum.snapmaker.com/u/MasterPrinter1)\ **Post date:** [October 18, 2026, 3:00pm UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/4 "2026-10-18T15:00:28Z")
yeah that affinity one’s sneakier than the json bug honestly. 0..15 by hand is a decent stopgap till they fix it ---
**Author:** ![Zoe\_M](https://avatars.discourse-cdn.com/v4/letter/z/8491ac/32.png) [@Zoe\_M](https://forum.snapmaker.com/u/Zoe_M)\ **Post date:** [October 19, 2026, 3:50am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/5 "2026-10-19T03:50:59Z")
Hi, thank you very much for the feedback. The topic has been forwarded to the senior engineer for further confirmation. I will keep you updated once there is any progress. Update: @dbvanhorn Hi, could you please try to submit a [support ticket](https://snapmaker.formcrafts.com/u1-troubleshooting-request)with the system log on the Snapmaker Orca V2.4.0: ![7f114c73-7504-44f4-96ea-25fc62beca12](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/7/5/753c1d11dcb6c9b17bb434effed954bc01f0912b.png) Wait for your reply. Best regards. ---
**Author:** ![dbvanhorn](https://avatars.discourse-cdn.com/v4/letter/d/58956e/32.png) [@dbvanhorn](https://forum.snapmaker.com/u/dbvanhorn)\ **Post date:** [October 19, 2026, 5:37am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/6 "2026-10-19T05:37:35Z")
When it crashes, there are no logs. It’s a hard abrupt crash. ---
**Author:** ![Zoe\_M](https://avatars.discourse-cdn.com/v4/letter/z/8491ac/32.png) [@Zoe\_M](https://forum.snapmaker.com/u/Zoe_M)\ **Post date:** [October 19, 2026, 6:22am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/7 "2026-10-19T06:22:29Z")
Hi, thanks for the quick reply. Could you please help me check whether there are any logs under the following file pathes: (If yes, can you help me compress this directory and share it via support ticket?) `%localappdata%/CrashDumps` ![9a3f155d-c42d-4ef3-b3b6-352575ba0372](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/c/6/c6fdde6d4ec6992c53b0cf523d4ac69ff3be4e67.jpeg) `%localappdata%/Snapmaker_Orca` ![e3df3ff8-8edb-4920-841b-e307916d0907](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/5/4/5474e145207f880d18196b0667bf03fa9fc20f0c.jpeg) ---
**Author:** ![dbvanhorn](https://avatars.discourse-cdn.com/v4/letter/d/58956e/32.png) [@dbvanhorn](https://forum.snapmaker.com/u/dbvanhorn)\ **Post date:** [October 19, 2026, 2:28pm UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/8 "2026-10-19T14:28:43Z")
> [@Zoe\_M](#): > > localappdata/CrashDumps 09/03/2026 11:34 AM . 10/17/2026 02:28 PM .. 08/21/2026 11:34 AM 3,483,787 AsusLibra.exe(1).16212.dmp 09/03/2026 11:34 AM 3,500,895 AsusLibra.exe(1).25360.dmp 08/21/2026 11:34 AM 3,489,619 AsusLibra.exe.16212.dmp 09/03/2026 11:34 AM 3,506,711 AsusLibra.exe.25360.dmp 05/30/2024 04:25 PM Malwarebytes 12/21/2025 09:09 PM 5,133,643 RazerCortex.exe.19800.dmp 12/21/2025 03:04 PM 5,110,706 RazerCortex.exe.20220.dmp 12/20/2025 10:56 AM 5,060,257 RazerCortex.exe.20840.dmp 12/22/2025 07:04 PM 5,234,419 RazerCortex.exe.26204.dmp 12/25/2025 10:03 PM 5,096,445 RazerCortex.exe.2916.dmp 05/11/2026 04:48 AM 7,076,767 RazerCortex.exe.6088.dmp 10 File(s) 46,693,249 bytes 3 Dir(s) 618,013,278,208 bytes free ---
**Author:** ![Zoe\_M](https://avatars.discourse-cdn.com/v4/letter/z/8491ac/32.png) [@Zoe\_M](https://forum.snapmaker.com/u/Zoe_M)\ **Post date:** [October 20, 2026, 2:17am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/9 "2026-10-20T02:17:29Z")
Hi, they seem to be the file list names. Can you zip the whole folder and share to the technical support team:[https://snapmaker.formcrafts.com/u1-troubleshooting-request](https://snapmaker.formcrafts.com/u1-troubleshooting-request) ---
**Author:** ![dbvanhorn](https://avatars.discourse-cdn.com/v4/letter/d/58956e/32.png) [@dbvanhorn](https://forum.snapmaker.com/u/dbvanhorn)\ **Post date:** [October 20, 2026, 4:44am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/10 "2026-10-20T04:44:22Z")
I was just showing that I don’t think there are any log files that you’d find useful. ---
**Author:** ![Zoe\_M](https://avatars.discourse-cdn.com/v4/letter/z/8491ac/32.png) [@Zoe\_M](https://forum.snapmaker.com/u/Zoe_M)\ **Post date:** [October 20, 2026, 6:18am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/11 "2026-10-20T06:18:51Z")
I see 😮 .How about this one: `%localappdata%/Snapmaker_Orca` ---
**Author:** ![dbvanhorn](https://avatars.discourse-cdn.com/v4/letter/d/58956e/32.png) [@dbvanhorn](https://forum.snapmaker.com/u/dbvanhorn)\ **Post date:** [October 20, 2026, 6:47am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/12 "2026-10-20T06:47:08Z")
[![](https://us1.discourse-cdn.com/flex022/uploads/snapmaker/original/3X/b/c/bcec071d2daf94f074e0d45f573498975b42d6b0.png)Snapmaker\_Orca.zip](https://drive.google.com/file/d/1pHVCHT0pr4tARTuI2gLM2btJtDyFJM9p/view?usp=drive_web) ---
**Author:** ![Zoe\_M](https://avatars.discourse-cdn.com/v4/letter/z/8491ac/32.png) [@Zoe\_M](https://forum.snapmaker.com/u/Zoe_M)\ **Post date:** [October 27, 2026, 6:20am UTC](https://forum.snapmaker.com/t/fatal-bug-in-slicing/43677/13 "2026-10-27T06:20:14Z")
Split this topic on October 27, 2026, 6:20am UTC A post was split to a new topic: [[Third Party Software]CADGuide.tools](https://forum.snapmaker.com/t/third-party-software-cadguide-tools/43802)