3xD 2.0-rc2 release notes
11 November 2026 · Release candidate · Pending owner approval
Compared with the previous complete 1.7-rc2 release, this complete kit includes reversible bearing carriers with the selected 12.80 mm bore, matching compact pod sockets for the printed chassis, the sloping recessed-logo bumper and the original unreinforced A1 retainer adapted for M3×8 screws. Single-car 3MF projects are now included with both kits.
Rear bearing carriers: replace matching parts together
Printed 4 mm chassis: replace BOTH carriers AND BOTH pod sides. The new compact 16 mm carriers use lowered, open-bottom sockets and are incompatible with the old printed 18 mm sockets/fixed 45 4C inserts. Axle settings are 7.9/8.4 mm above pod top; nominal lower-edge clearance to the plate is 0.15 mm. No separate support ledge is added.
GRP 3 mm chassis: keep the existing pod sides and replace both inserts. The existing 18 mm socket envelope remains; axle settings are 8.9/9.4 mm above pod top. Both versions retain the flanged-bearing stop, 14.6 mm flange relief, 0.8 mm backing and 10 mm axle clearance.
The 12.80 mm bore is owner-selected from the fit coupon. Read the upright top mark: L = axle lower, H = axle higher, not tyre size or chassis ride height. Match both sides and reset gear mesh after changing height. Clip retention, actual flange fit, motion and durability still require physical checks.
Sloping bumper with recessed 3xD logo
The bumper now has a continuous 11.44° sloping top, rear higher, and is supplied inverted for supports-off printing intent. A 30 × 8 mm central land leaves 35 complete honeycomb openings. The actual traced 26 mm logo is recessed 0.4 mm normal to the roof. Existing 48 mm mounts, nut seats, M3×10 screws and chassis-relative underside are retained. Reprint the bumper; check TPU bridges and body-shell clearance.
Original A1 retainer: M3×8 and 0.08 mm layers
The original A1 snap cavity, throat, slots and unreinforced roots are retained. The upper mounting section is 2 mm taller (10.32 mm total); 2.5 mm pilots are 5.52 mm deep. Use two M3×8 countersunk screws through the 3 mm pod plate used on both chassis setups: 5 mm nominal engagement, 0.52 mm tip clearance and 1.28 mm blind cap. Replace the retainer and its two screws; do not put M3×8 screws into the historical M3×6 retainer.
The retainer uses 0.08 mm layers. Complete projects use a common 0.20 mm first layer; the supplied standalone precision plate uses a 0.08 mm first layer. No B1/B2 or reinforced-root part is selected. Check screw seating, articulation and upper-body stiffness physically.
Complete kits and single-car print projects
- Complete 2.0-rc2 — 4 mm printed chassis kit
- Single-car 3MF — printed chassis, 46 pieces on six plates
- Complete 2.0-rc2 — 3 mm GRP chassis kit
- Single-car 3MF — GRP setup, 44 printed pieces on five plates
Each kit contains 43 distinct STL selections and 46 required part instances, plus hardware lists, cutting files, manifests and validation. The printed project includes the 4 mm chassis and 3 mm pod plate. The GRP project excludes the two GRP sheets from printing; their cutting files are included. Default 4-1 arms use the camber-1 brace. Optional tuning arms and shims remain separate STL choices. PETG pod sides/motor flange/spacers and the TPU bumper have separate plates.
Comparison and validation
Against complete 1.7-rc2, six selections change in the printed kit (37 unchanged); four change in GRP (39 unchanged). The pivot identifier changes from M3×6 to M3×8. This packages the existing 1.8-rc3 bumper, 1.9-rc1 pivot and 2.0-rc1 carrier changes without new geometry.
Frozen source/archive hashes, quantities and all embedded 3MF meshes were checked, along with placement, grounding, spacing and bed bounds. Projects were generated directly and remain unsliced. CAD validation does not establish printed clip strength, TPU bridge quality, full suspension travel, gear mesh or endurance. Front 5 mm spring-stack checks also remain pending. No print job was sent. Publication is not design approval or a competition-compliance claim.