The 3D Systems VisiJet RWT-EBK-A90 material set is a paired support-and-build consumable for MultiJet Printing. It combines VisiJet CR-WT 200**, a removable wax support, with VisiJet CE-BK, a black elastomeric build material. The commercial designation encodes removable wax technology, elastomeric black build material, and Shore A 90 durometer. It is qualified on the ProJet MJP 2500 Plus platform, which deposits layers at 32 µm and provides a build envelope of 294 mm × 211 mm × 144 mm. In service, the support phase is removed by melting rather than solvent dissolution; the resulting CE-BK phase remains as a black elastomer for seals, gaskets, wearable pads, soft-touch housings, dampening elements, and functional rubber-like prototypes.

What Qualified Processing Boundaries Govern the RWT-EBK-A90 Support–Build Pair?

Qualified operation begins with sealed cartridge conditioning managed by the printer firmware. The VisiJet CR-WT 200** support formulation is jetted into regions that are later removed by a melt-away oven cycle at approximately 60 °C. The standard support-removal procedure does not require aggressive solvent washing; however, accessible wax removal depends on part geometry. Operators should not raise the oven setpoint beyond the qualified cycle to accelerate wax flow because thin-walled CE-BK sections can distort when heated above the intended removal window. The MJP platform controls cartridge identity, jetting temperature, and printhead energy, which reduces batch-to-batch substitution errors. On production MJP lines, the longest downstream step is typically support removal from blind holes, undercuts, and internal channels. Residual wax left in these regions can create localized contamination and weak interlaminar surfaces. Published process documentation for this specific material set does not assign a universal manual removal time; it scales with hollow geometry, wax mass, oven loading, and the orientation of drainage features.

The material set is not prepared by mixing the two formulations. VisiJet CR-WT 200** and VisiJet CE-BK are jetted through separate qualified cartridges and head channels. The firmware lockout prevents the use of non-qualified cartridge identifiers, which is a critical control for preserving the melt-away behavior of the wax support. In production, nozzle dropout can alter the interface between support and build material; missed nozzles in the transition zone may leave support residue locked under elastomer surfaces. Printhead maintenance intervals should follow the platform service schedule. Batch-to-batch variations in cartridge fill, pigment dispersion, and melt rheology are controlled by the manufacturer, but local part quality is governed by nozzle condition, build orientation, and oven loading.

Elastomeric Datasheet Values and Verification Standards for VisiJet CE-BK

The build material VisiJet CE-BK is a black elastomer with a nominal hardness of Shore A 90 under ASTM D2240. Representative datasheet values include tensile strength of approximately 10 MPa and elongation at break of approximately 280% when tested under ASTM D638; tear strength is approximately 33 kN/m under ASTM D624; and density is approximately 1.10 g/cm³ under ASTM D792. These values are generated on XY-oriented specimens at room temperature. Z-oriented tensile and elongation values can be lower because of layered jetting and should not be assumed equal to XY-oriented results. The final part is the CE-BK phase only after support removal; the CR-WT 200** phase is not intended to remain in service.

Mechanical response is influenced by print orientation, wall thickness, oven dwell time, and any post-removal heat history. For applications involving long-term compressive load, users should generate part-level data using ASTM D395 Method B because published data for this specific configuration is limited. For elastomer tensile verification on production parts, ASTM D412 or ASTM D638 may be selected depending on specimen geometry; the datasheet values should not be treated as design allowables without internal correlation. Dynamic fatigue, chemical aging, and high-humidity exposure are not comprehensively published for RWT-EBK-A90. Qualification programs should include cyclic flex testing, compression set testing, and media immersion studies according to the end-use environment.

Compression seals in CE-BK are commonly designed with 15% to 25% compressive strain at assembly. This range is typical for Shore A 90 elastomer seals but must be confirmed with production geometry because local strain can concentrate at corners, ribs, and closed-cell transitions. Thin-walled sections below 0.5 mm are printable but require additional support-removal attention because narrow slits may not fully drain molten wax without extended dwell time. Blind pockets deeper than 10 mm with closed ends are a known bottleneck on production MJP platforms; reducing pocket depth, adding drainage access, or increasing the open cross-section shortens wax removal and lowers the risk of embedded wax. Enclosed internal channels should include a vent or second opening to allow molten wax to drain. The black CE-BK phase is not a replacement for low-durometer silicone seals in Shore A 30 to Shore A 60 applications; its 90A durometer is better suited to higher-pressure seals, bump stops, and dampening pads where softer materials would extrude under load.

When RWT-EBK-A90 Replaces Cast Polyurethane, FDM TPU, or Older MJP Elastomer Kits

Compared with cast polyurethane at nominal Shore A 90, the RWT-EBK-A90 route eliminates mold tooling, which changes lead time for functional elastomer prototypes; however, cast polyurethane can offer higher bulk tear strength and larger cross-section consistency in some formulations. Relative to filament-deposited thermoplastic polyurethane, the MJP CE-BK surface is smoother and does not exhibit raster-driven porosity along layer boundaries, but the build volume is limited to 294 mm × 211 mm × 144 mm and the support-removal step is solvent-free rather than manually stripped. Compared with earlier MJP elastomer pairings, the CR-WT 200** support is formulated for the CE-BK build material, and substituting older support systems or third-party waxes can alter melt-away behavior, residue levels, and surface contamination. The set differs from rigid MJP build materials used for white or black shells; it is not intended for load-bearing rigid structural parts. Users requiring a rigid housing and an elastomeric seal can print the housing from a separate qualified MJP resin and assemble it with a CE-BK seal, but the RWT-EBK-A90 set itself is not a two-build-material rigid-elastomer package.

Production economics differ from cast or molded parts. MJP build time scales with volume and layer count, while cast polyurethane unit cost falls with mold amortization. RWT-EBK-A90 is positioned where Shore A 90 elastomeric geometry changes frequently or where consolidation of multiple seals into a single printable form reduces assembly cost. The standard platform does not include a validated process for printing CE-BK without the qualified support material; attempts to use alternative support materials violate the qualified printing matrix. This distinguishes the product from open-material polymer printers that permit third-party support substitution. The material set is also not a direct substitute for optical-clear elastomers or high-temperature fluorosilicone seals; CE-BK is black and is qualified around a Shore A 90 hardness envelope rather than a broad durometer range.

Storage, Compliance, and Operational Boundaries for the Wax-Elastomer Set

Cartridges for VisiJet CR-WT 200** and VisiJet CE-BK should be stored in sealed, light-restricted cartons and allowed to equilibrate to the printer room temperature before installation. The manufacturer’s safety data sheet for each formulation should be retained for workplace exposure control. The wax support and the elastomeric build material are not food-contact or implantable materials by default. Regulatory documentation for the European Union should confirm REACH obligations under Regulation (EC) No 1907/2006 and RoHS compliance under Directive 2011/65/EU before the finished device is placed on the market. Biocompatibility claims are not established for all part geometries; medical device use requires ISO 10993-1 evaluation on the final cleaned part.

Solvent cleaning with ketones, esters, or chlorinated solvents should be avoided unless swelling behavior is validated by ASTM D543 or ISO 175. The support-removal oven should be operated at the qualified temperature near 60 °C; high-temperature acceleration above the qualified cycle is outside published data for this material pair. Prolonged service above 60 °C can induce compression set in the elastomer; validation should follow ASTM D395 Method B under actual part deflection. Repeated flexing should be tested with a coupon-level fatigue method because published data for this specific configuration is limited.