Drafted the technical task

TECHNICAL TASK (TT)

Project: Modernization and optimization of a PC case in a desk format (Slim & Light version)

1. General information and project goal

Based on the basic (previous) 3D model of the desk-case, a redesign and complete optimization of the structure is required. Main goal: to make the case significantly lighter, technologically suitable for serial laser cutting and bending, and fully adapt it for direct installation of electric lifting supports from the LUMI M17-23D system.

2. Geometric constraints and dimensions

The design must strictly adhere to the following spatial limits:

• Width of the desk: no more than 1600 mm (overall external dimension).

• Thickness (height of the case): no more than 140 mm (from the lowest point of the desk bottom to the upper surface of the glass). This is critical to ensure comfortable leg space for the user.

• Depth of the desk: optimally 700–800 mm (determined by the engineer during layout to achieve the best ergonomics and weight balance).

3. Technical requirements and integration of LUMI M17-23D lifting supports

• Direct mounting of columns: The design of the mounting points on the bottom of the desk-case must be strictly under the geometry and mounting holes of the upper brackets of the LUMI M17-23D lifting supports (columns). The factory sliding frame is not used — the desk case itself acts as a load-bearing truss.

• Power integration and rigidity: Since the supports are attached directly to the PC case, the bottom of the desk at the mounting points of the supports must be locally reinforced (for example, with ribs of rigidity or additional plates with a thickness of 2.0–3.0 mm). The structure must withstand static and dynamic loads (up to 180 kg according to the specifications of the supports) without metal deformation and play during movement.

• Placement of the control unit and cables: The electronic power controller of the supports and excess wires from the motors of each column must be hidden inside a specially designed technological compartment (or tray) within the PC case.

• Control panel: Design an ergonomic window or integrated bracket for rigid fixation of the standard LUMI button remote on the front (or side) edge of the metal desk case.

• Vibration and static protection: The engineer must provide dielectric or rubber damping pads at the junctions of the columns with the case to dampen micro-vibrations during motor startup, as well as establish a general grounding for the entire metal PC case.

4. Structural requirements and internal filling (PC components)

The internal architecture must ensure logical and convenient placement of the following nodes:

• 4.1. Mounting points, fastening, and ergonomics:

  • Motherboard: Form factors ATX / E-ATX. Provide a removable or integrated chassis with stampings (or pressed stands) and windows for the CPU cooling backplate.

  • Graphics card: Horizontal (parallel to the board) installation using a flexible extender (Riser PCIe). Calculate space for top cards (length up to 360 mm, thickness up to 4 slots — for example, RTX 4090 / RTX 5090).

  • Monitor bracket: On the back wall/panel of the desk, provide a universal area (or special cut/reinforced recess) for installing a desktop bracket for 1–3 monitors. This area must be structurally reinforced with an additional profile or increased metal thickness (at least 2.0–3.0 mm) to counteract the torque (“lever effect”) from the weight of the monitors. The glass of the top cover should not be subjected to pressure from the bracket clamp.

• 4.2. Power supply: Form factor ATX. Organize isolated intake and exhaust air for the power supply, so its heat does not mix with the main case circuit.

• 4.3. Cooling (CPC): Mandatory support for at least two 360 mm or 420 mm liquid cooling radiators. Flow zoning must exclude overheating of components. Fan holes must have mounting points for magnetic or retractable dust filters.

• 4.4. Interface panel (I/O): Design a window on the front or side edge for the module: Power Button, 2x USB 3.0, 1x USB Type-C, HD Audio.

5. Weight optimization, materials, and technology

• Weight reduction: Achieve weight reduction by:

  1. Optimizing the thickness of sheet metal (for example, the power frame and bottom — steel 1.5 mm; internal partitions, trays, and holders — steel 1.0 mm or aluminum 1.2–1.5 mm).

  2. Implementing functional perforation (through patterns that reduce weight and improve ventilation).

• Technological suitability: The design must be oriented towards minimum welding work. Priority — laser cutting, bending on CNC sheet metal benders, assembly with pull rivets, screws, and pressed bolts (threaded rivets).

• Top cover: Tempered glass with a thickness of 5–6 mm, installed flush with the metal edges of the desk using a rubber or silicone damping seal.

6. Output file requirements (Engineer’s deliverables)

Upon completion of the project, the engineer must provide a set of documentation for production:

1. 3D model of the product: in STEP or IGES format, as well as source files in the engineering environment (Fusion 360 / SolidWorks).

2. Layouts for laser: Files in DXF format (scale 1:1) separately for each part with clear marking of metal thickness and indication of bending lines. (upon agreement) - if the 3D model of the product is of high quality, the manufacturing plant will do this.

3. Bending drawings: Files in PDF format indicating linear dimensions after bending, radii, and angles.

4. (upon agreement) - if the 3D model of the product is of high quality, the manufacturing plant will do this.

5. Bill of Materials (BOM): A list of all fasteners (screws, washers, bolts), fittings, and purchased components (riser, buttons, etc., to be agreed with the project customer).

Note for the engineer: It is essential to consider the metal stretch coefficient (K-factor) for specific matrices and punches for bending sheet metal with a thickness of 1.2–1.5 mm. Check the ergonomics of the user's legs in a seated position at the minimum height of the desk considering the case thickness of 140 mm. Given that the minimum height of the LUMI M17-23D legs is 620 mm, the final height of the desk at the top glass will be from 760 mm.