3xD 2.9-rc1 release notes
12 November 2026 · Release candidate · Pending owner approval
Compared with complete 2.8-rc2, both chassis kits now use the owner-selected three-dot, 12.70 mm rear guide cap. The largest trial cap was reported to fit best. Its exact tested mesh is retained, replacing the previous 12.4 mm production cap.
Downloads
- Complete kit — 4 mm printed chassis
- Printed chassis single-car 3MF — 46 pieces / seven plates
- Complete kit — 3 mm GRP chassis
- GRP single-car 3MF — 44 printed pieces / six plates
What changes
Replace only the removable rear O-ring guide cap. One STL selection changes; 42 remain unchanged per setup. Each kit has 43 distinct STL selections and 46 required physical pieces. The guide body, O-ring, rear spring, hardware and separate A1 ball-pivot retainer remain unchanged. Front arms remain default 4-1.
The cap keeps its 5.8 mm central bore, 1.2 mm base, 3.2 mm overall height and 10 mm spring-lip inside diameter. Three recessed dots identify the selected 12.70 mm size. Both chassis versions use one identical cap per car, retaining their separate chassis and pod geometry.
The smaller 12.5 and 12.6 mm trials and obsolete mixed trial projects have been removed from active working selections. Frozen historical releases remain preserved. Use the selected cap in this release rather than an old mixed print job.
Printing and checks
Print the cap flat base down in PLA at 0.08 mm including the first layer, four walls, 100% infill and no supports. Both complete single-car projects include it. The printed project includes its 4 mm chassis and 3 mm pod plate; GRP sheet parts remain separate cutting files. Other materials, orientations and selective support settings are retained from 2.8-rc2, including the separate SUNLU PA6-CF pod-parts plate and its provisional calibration requirement.
The selected cap matches the frozen sample-3 hash. Its OpenSCAD export, dimensions and closed-solid mesh were checked. Both 3MFs passed embedded-mesh, quantity, XML reference, material, grounding, spacing and bed-bound checks. Projects remain unsliced.
Cap fit is owner-selected. Full suspension motion and endurance have not been established by that fit report. Selection of this cap and website publication do not approve the whole release candidate.