Vertex K8400 Dual

The Vertex K8400 Dual is an FDM 3D printer from Velleman N.V. with a 180 x 200 x 190 mm build volume.

Specifications

The Vertex K8400 Dual 3D printer is a dual-extrusion version of the Cartesian machine developed by the Belgian company Velleman N.V. Built as a DIY kit or upgraded from a single-nozzle setup, it offers entry into multi-material printing. It targets advanced hobbyists, educational laboratories, and design engineers who want to print complex geometries using soluble or breakaway support structures.

Kinematics and Mechanical Configuration (Cross-Rod Cartesian Dual Extrusion)

The Vertex K8400 Dual relies on a cross-rod Cartesian motion system. The print carriage hosts two separate hotends mounted side-by-side.

Calibration

Dual extrusion requires precise calibration. Any mechanical misalignment in X, Y, or Z between the two nozzles will cause offset layers or lead to the inactive nozzle colliding with the printed part.

• Mechanical Z-Height Leveling of Both Nozzles

If one nozzle sits lower than the other (even by 0.05 mm), it will scrape the plastic layers deposited by the active nozzle, ruining the print or detaching the model from the bed.

Common defects

• Hardware defects and mechanical weaknesses
• Plastic Carriage Bracket Flex: The stock carriage bracket holding both hotends is made of plastic. Over time, exposure to hotend heat can cause it to flex, altering the Z-distance between the nozzles and leading to print failures. Solution: Upgrade to an aluminum carriage bracket or print a replacement using high-temperature polycarbonate filament.

What it is used for

Best use-cases

• Intricate Designs with Soluble Supports: Printing hollow parts, internal channels, and complex geometries where PVA support structures can be dissolved in water.
• Dual-Color Prototyping: Creating scale models, signs, or educational tools with two distinct colors without post-processing or painting.