Support/Raft Interface Applied Incorrectly on Tree Supports #2166

New Issue

MrUnknownDE · 2026-04-06T00:53:08+02:00

MrUnknownDE commented

2026-04-06 00:53:08 +02:00

Originally created by @The1CheetahAssassin on 9/16/2025

Is there an existing issue for this problem?

I have searched the existing issues

OrcaSlicer Version

2.3.0

Operating System (OS)

Windows

OS Version

Windows 11

Additional system information

No response

Printer

Bambu P1S and Snapmaker U1

How to reproduce

Start with a model/part with a floating region that needs to be supported from another part (not from the build plate)
Set base part material to filament 1
Set support/raft interface to filament 2 (in my case, PETG supports for PLA but anything works)
Optionally, force support/raft base material to filament 1 depending on the model being printed (we're just trying to force the interface to be the only different material)
Select tree (auto) supports as the type
Set support style to either Default or Organic

Actual results

The bottom interface of the supports (that sits on top of the part) uses the same filament as the part. Top interface will be the selected interface filament.

Expected results

Both the top and bottom interfaces of the support structure should be the interface material. This behavior works for grid, tree slim, tree strong, and tree hybrid. Tree organic is the only support type where the materials do not correctly change.

Project file & Debug log uploads

Support Interface Bug Report 2025-09-16.zip

Checklist of files to include

Log file
Project file

Anything else?

Attached are several images that showcase the expected results with grid and tree slim/strong supports as well as images that show the incorrect result that is generated with organic/default tree supports.

*Originally created by @The1CheetahAssassin on 9/16/2025* ### Is there an existing issue for this problem? - [x] I have searched the existing issues ### OrcaSlicer Version 2.3.0 ### Operating System (OS) Windows ### OS Version Windows 11 ### Additional system information _No response_ ### Printer Bambu P1S and Snapmaker U1 ### How to reproduce 1. Start with a model/part with a floating region that needs to be supported from another part (not from the build plate) 2. Set base part material to filament 1 3. Set support/raft interface to filament 2 (in my case, PETG supports for PLA but anything works) 4. Optionally, force support/raft base material to filament 1 depending on the model being printed (we're just trying to force the interface to be the only different material) 5. Select tree (auto) supports as the type 6. Set support style to either Default or Organic ### Actual results The bottom interface of the supports (that sits on top of the part) uses the same filament as the part. Top interface will be the selected interface filament. ### Expected results Both the top and bottom interfaces of the support structure should be the interface material. This behavior works for grid, tree slim, tree strong, and tree hybrid. Tree organic is the only support type where the materials do not correctly change. ### Project file & Debug log uploads [Support Interface Bug Report 2025-09-16.zip](https://github.com/user-attachments/files/22372055/Support.Interface.Bug.Report.2025-09-16.zip) ### Checklist of files to include - [ ] Log file - [x] Project file ### Anything else? Attached are several images that showcase the expected results with grid and tree slim/strong supports as well as images that show the incorrect result that is generated with organic/default tree supports. <img width="1456" height="730" alt="Image" src="https://github.com/user-attachments/assets/1eaffcb4-9737-4ba2-9706-7cc814c8ce59" /> <img width="1457" height="683" alt="Image" src="https://github.com/user-attachments/assets/806e892d-5ab6-49e9-b89a-0e48ed565bf4" /> <img width="989" height="575" alt="Image" src="https://github.com/user-attachments/assets/958f33fa-4d00-4cc4-a37f-faad67d894b2" /> <img width="898" height="721" alt="Image" src="https://github.com/user-attachments/assets/0a13a87d-81e0-458d-b012-f096adbd317b" /> <img width="675" height="801" alt="Image" src="https://github.com/user-attachments/assets/3955b1a4-d2f8-4308-a91c-83e4370e5375" /> <img width="1468" height="740" alt="Image" src="https://github.com/user-attachments/assets/635e066c-38ee-41bc-9826-6704bd0ad486" /> <img width="1471" height="755" alt="Image" src="https://github.com/user-attachments/assets/296be6fc-535a-4092-923a-6ba2d71a97df" /> <img width="1527" height="741" alt="Image" src="https://github.com/user-attachments/assets/2b3a9d8d-0f51-4602-832f-ebe3923c9545" />

Sign in to join this conversation.

No Label bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug bug

1 Participants

Notifications

Due Date

No due date set.

Dependencies

No dependencies set.

Reference: github/OrcaSlicer#2166