In the Rigur rigid opaque PolyJet combination, VeroBlackPlus RGD875 forms the rigid phase while TangoBlackPlus FLX980 or TangoPlus FLX930 supplies the elastomeric phase. In consumer wearable and handheld electronics enclosures, the two phases are jetted within one build so that a rigid black housing receives an integrated elastomeric button membrane, gasket, or strap anchor without secondary bonding. The RGD875 phase is specified by the manufacturer at Shore D 83–86, tensile strength 50–65 MPa per ASTM D638-14, flexural strength 75–110 MPa per ASTM D790-17, and flexural modulus 2,200–3,200 MPa per ASTM D790-17. The FLX980 or FLX930 phase is specified at Shore A 26–28, tensile strength 0.8–1.5 MPa, and elongation at break 170–220% per ASTM D412-16. For a wrist-worn wearable prototype, the housing is generated at 16 µm layer height while a Shore A 40 digital material button bladder is jetted in the same build through the DM engine, which varies voxel-level deposition of RGD875 and FLX980 rather than creating a bulk mixture. Support is removed with a high-pressure water jet at 50–80 bar, and the process is constrained by the low tear resistance of the pure elastomer phase: walls below 0.8 mm in Shore A 27 regions can perforate during jetting, and blind clip cavities below 1.5 mm can retain support gel that artificially raises durometer before post-cure. The cured polymer article falls under the heavy-metal restrictions of RoHS 2011/65/EU, but no skin-contact or biocompatibility claim is published under ISO 10993 for this specific RGD875/FLX980 combination. Snaps and button blisters are validated on a tensile test frame at 100 mm/min with force stability expected within ±0.3 N across 100 cycles for a 1.0 mm wall, though published data for this exact configuration is limited and production-target verification under ASTM D638-14 and ASTM D2240-15 is required.

When Does a Single-Build Rigid-Flexible Medical Model Replace Separately Assembled Anatomy?

Hospital-based anatomical modeling laboratories select the RGD875/FLX980 combination when a patient-specific bony structure must be printed as a rigid opaque analogue while adjacent soft tissue is printed as an elastomeric structure within the same job. The source imaging stack is segmented from DICOM data at a slice interval of 0.5–1.0 mm, and the bone surface is exported as a stereolithography file for the rigid phase. The RGD875 bone analogue is jetted at 16 µm layer height to preserve cortical landmark resolution, while the FLX980 soft-tissue analogue is jetted adjacently at Shore A 26–28 or as a Shore A 40 digital material if greater dissection resistance is required. On a PolyJet system with dual tray capacity, the two phases are UV-cured in situ and the interface is formed by droplet-level interlocking, which removes the delamination plane associated with adhesive assembly. Support removal from tortuous vascular or nerve volumes uses a water jet at 40–70 bar; elastomer branches below 0.6 mm are vulnerable to perforation, so segmentation is dilated by 0.2–0.3 mm before printing to reinforce those structures. The printed model is handled as a non-sterile anatomical reference, governed by design-control procedures under ISO 13485:2016 when fabricated in a hospital quality system, and it does not require ISO 10993 certification unless it enters a sterile field. Where the model is used for preoperative rehearsal, the build sheet is reviewed for layer-to-layer tensile discontinuities under ASTM D638-14 because a digital material interface can show lower elongation at break than either pure phase; published data for the exact RGD875/FLX980 interface is limited, so sacrificial dog-bone specimens are printed in the same build for mechanical verification. Dimensional tolerance on a calibrated system is typically within ±0.1 mm for features above 50 mm, while features below 10 mm may require a compensation factor of +0.15 mm to offset shrinkage. Unsealed FLX980 surfaces can retain solvent-wiped pigments and low-molecular-weight residues, so a clear non-reactive coating is applied only when the clinical workflow demands repeated cleaning.

During automotive wire-harness clip and grommet prototyping, the RGD875/FLX980 system exposes the tension between rigid snap geometry and elastomeric anti-rattle compliance. The clip body is generated in RGD875 because the material provides Shore D 83–86 and flexural modulus 2,200–3,200 MPa per ASTM D790-17; the grommet collar is generated in FLX980 or a Shore A 40–60 digital material to fill hole tolerances and damp vibration. The build is processed at 27 µm layer height for faster firewall, trunk, and instrument-panel iterations, followed by water-jet support removal at 60–80 bar. Orientation is process-critical: the snap beam is aligned with the X-axis rather than the Z-axis because Z-stacked FLX980 interlayers beneath the beam can reduce snap engagement force through uncontrolled interlayer shear. Vibration testing follows ISO 16750-3 for interior service profiles, but continuous engine-bay exposure is outside the published thermal boundary because RGD875 heat deflection temperature is specified at 45–50 °C under 0.45 MPa. Insertion and extraction cycling is performed for 50 cycles at 100 mm/min, with acceptance limits derived from production PP/POM baseline parts rather than from this digital material alone. The elastomer collar is evaluated for compression set under ASTM D395-16; Shore A 27 FLX980 collars show greater permanent deformation than Shore A 60 digital material collars under identical load, so grommets requiring retained radial force above 5 N after 24 h at 23 °C are specified at Shore A 60. In-cabin parts must also pass the vehicle manufacturer’s odour and fogging specifications, and uncured residue from inadequate support removal can contribute volatile compounds, so parts are rinsed and UV post-cured before delivery. The resulting clip set functions as a single-build replacement for a multi-component injection-moulded assembly in engineering validation, not as a production substitute for PP or PA66.

If Compression Set and Shore A Gradient Are the Dominant Variables in Footwear Prototyping

For orthotic insole and midsole prototyping, the digital material gradient between FLX930 and RGD875 produces distinct load-bearing zones without adhesive lamination. Pure FLX930 is specified at Shore A 26–28, tensile strength 0.8–1.5 MPa, and elongation at break 170–220% per ASTM D412-16, while RGD875 inserts are used only at the heel counter or shank position where flexural modulus 2,200–3,200 MPa is required. Digital material ratios generating Shore A 40, 50, 60, and 85 are printed by varying the deposition ratio of RGD875 to FLX980/FLX930 in the DM engine, with each ratio jetted as a voxel matrix rather than a homogeneous bulk mixture. The build is performed at 16 µm layer height to reduce plantar-surface layer lines, and gel support is removed with a water jet at 40–60 bar; the insole is then dried under vacuum at 23–25 °C for 24 h to prevent moisture uptake from shifting durometer readings. Hardness is verified with ASTM D2240-15 after conditioning for 48 h at 23 °C and 50% RH, and readings are taken on flat zones at least 6 mm thick because the digital material skin layer can read one Shore A step lower on thin sections. Compression set is measured under ASTM D395-16 method B at 23 °C for 24 h; unreinforced FLX930-rich zones may show compression set above 20%, so a heel-strike simulator protocol of 100,000 steps is applied to establish creep recovery before prototype validation. Published dynamic fatigue data for the exact RGD875/FLX930 digital gradient is limited, so the design is derated by limiting peak plantar pressure to 300 kPa in elastomer-only zones and transferring higher loads to Shore A 85 or RGD875 stiffening elements. The final orthotic prototype is not automatically a medical device substitute and falls outside FDA 21 CFR 820 unless the provider submits it as a custom orthotic under the relevant device classification; material safety documentation follows the supplier’s REACH declaration for cured polymer articles. Table 1 summarizes the Shore A gradient used in this application.

A recurring failure mode in collaborative robot gripper fingers and vacuum cup adapters is the separation of the soft contact pad from the rigid mounting flange during reversing shear loads. The RGD875/FLX980 combination addresses this by printing the rigid flange and Shore A 26–28 FLX980 contact lip as a droplet-interlocked single body, eliminating mechanical clamping of rubber pads. The rigid flange is jetted at 16 µm layer height to maintain the ISO 9409-1 tool-plate hole pattern, while the compliant lip is printed with a wall thickness of 1.2–1.5 mm to resist peeling. The process boundary is the undercut geometry: unsupported elastomer overhangs below 45° require sacrificial gel support that must be removed carefully at 40–60 bar, because higher pressure can delaminate the FLX980 lip from the RGD875 body at the inter-material interface. Contact pressure distribution is tested under ISO/TS 15066 for collaborative operation, and Shore A consistency is checked with ASTM D2240-15; edge readings can drift by ±1 Shore A if the UV lamp intensity is not calibrated across the build bed. In a pick-and-place trial of 500,000 cycles at 0.5 Hz, the FLX980 lip may show leading-edge abrasion, so a wear allowance of 0.2 mm is added to the lip geometry. The material combination is not specified for direct food contact, and any gripper used in food packaging requires an indirect-contact barrier film or a food-grade cover compliant with EU 10/2011. The printed end-effector is intended for industrial and laboratory automation, where the digital-material lip absorbs part tolerance variation up to ±0.4 mm across a sheet-metal panel stack; published shear-strength retention data for this exact interface is limited, and batch validation under ASTM D624-12 tear testing is required.

Production-Fixture Seal Nests, Flexible Locators and Short-Run Compliance Features

In short-run production fixtures, seal nests and modular locator pads use RGD875 as the dimensionally stable base and FLX980 or FLX930 as the contact pad, seal lip, or clamp cushion. The base is built at 27 µm layer height with RGD875 because Shore D 83–86 and flexural modulus 2,200–3,200 MPa maintain datum stability, while the contact surfaces are printed in Shore A 40–60 digital material to protect polished or coated workpieces. The digital material transition is placed at least 1.0 mm below the contact plane, because a transition line at the surface creates a micro-gap that retains cutting fluid and distorts seal compression. Support removal is performed with a water jet at 50–70 bar, and the fixture is dried for 12 h at 25 °C before dimensional inspection because FLX930 can absorb airborne moisture that shifts compression behavior by up to 5% in high-humidity assembly shops. Seal rings and vacuum cups printed from FLX930 are tested for tear resistance under ASTM D624-12 and for Shore A under ASTM D2240-15; compared with moulded polyurethane or liquid silicone rubber, the pure elastomer phase has lower tear strength, so seal groove depth is limited to 0.8 mm and gland fill is held below 15–20% to avoid over-compression and shear failure at assembly. Fixtures comply with the dimensional control clauses of ISO 9001:2015 and the supplier’s REACH and RoHS declarations, but continuous immersion in ketone, chlorinated, or aromatic hydrocarbon cleaning agents is outside the compatibility envelope because the elastomer phase can swell and lose Shore A hardness; solvent exposure requires compatibility testing under ISO 175:2010. The final fixture is a bridge tool or prototype assembly aid, not a replacement for hardened steel or anodized aluminium production nests when cycle counts exceed 100,000 insertions or when abrasive workpiece edges are present. Because the FLX930 phase is not vulcanized and does not develop the crosslinked network of an injection-moulded thermoset, fixture maintenance intervals must be set by periodic ASTM D2240-15 durometer screening.