Product Specifications
Self-Contained CNC Sand-Blasting Cabinet
CoreXY Architecture with mm-Level Depth Control
1. Purpose & Scope
Design a portable, closed-loop sand-blasting cabinet capable of automated removal of floor adhesives, paint, and light surface contamination on wood, metal, or composite substrates. The system must:
- Contain >95% of abrasive and dust emissions
- Achieve ≤1 mm depth-of-cut accuracy across a 600×600 mm work envelope
- Integrate G-code motion control for repeatable toolpaths from CAD/CAM or on-board macros
2. Target Applications
| Use Case |
Success Criterion |
| Glue removal on plywood/OSB sub-floor |
Residual adhesive ≤0.3 mm, no veneer gouging |
| Paint stripping on small steel panels |
≤10 µm profile Ra after single pass |
| Precision texture on hardwood inlays |
Depth variance ≤0.5 mm over 600 mm span |
| Parameter |
Target |
Rationale |
| X-Y repeatability |
≤0.05 mm |
CoreXY belts with 0.9° steppers @ 32 µstep |
| Z-axis stand-off repeatability |
≤0.10 mm |
Leadscrew + inductive probe |
| Depth sensor repeatability |
≤0.5 mm (Z) |
Meets wood-floor flatness spec (3 mm in 3 m) |
| Abrasive flow rate |
0–2 kg min⁻¹ soda at 80–120 psi |
Matches removal rate ~1 m² min⁻¹ |
| Recovery efficiency |
≥95% grit captured |
Minimize media cost, dust |
| Cabinet negative pressure |
−50 Pa to −150 Pa |
Prevents leaks at skirt & seams |
| Noise level @1 m |
≤95 dB(A) |
Ear protection still required |
4. System Architecture
flowchart TD
A[Motion Gantry<br/>CoreXY + MGN12 Rails] --> B[Blast Nozzle + Shroud]
B --> C[Workpiece<br/>Perforated Bed]
C --> D[Vacuum Return]
D --> E[Cyclone Separator]
E --> F[Reusable Grit]
F --> G[Hopper]
G --> H[Pressure Pot]
H --> B
E --> I[HEPA Filter]
I --> J[Exhaust]
%% Styling
classDef motionSystem fill:#e1f5fe,stroke:#01579b,stroke-width:2px
classDef blastSystem fill:#f3e5f5,stroke:#4a148c,stroke-width:2px
classDef recoverySystem fill:#e8f5e8,stroke:#1b5e20,stroke-width:2px
classDef filtrationSystem fill:#fff3e0,stroke:#e65100,stroke-width:2px
class A motionSystem
class B,H blastSystem
class C,D,E,F,G recoverySystem
class I,J filtrationSystem
Subsystems:
- Mechanical Frame – 40×40 mm aluminum T-slot cage (900×800×700 mm)
- Blast & Recovery Loop – 20L ASME pot; Ø6 mm carbide nozzle; regenerative blower 180 CFM
- Depth-Sensing Loop – 2-D laser triangulation profiler (Keyence LJ-V7000 series)
- Control Electronics – Duet 3 Mini 5+ (CAN-FD expansion) located outside cabinet
- Safety & Filtration – NFPA-compliant grounding, HEPA H13 cartridge with auto-pulse
5. Mechanical Design
| Feature |
Specification |
| Frame material |
6063-T6 extrusions, anodised; corner plates with stainless M8 hardware |
| Panels |
6 mm polycarbonate windows, 3 mm powder-coated steel elsewhere; all seams with neoprene gaskets |
| Motion rails |
MGN12 linear rails, dual-driven CoreXY belts (GT2-6 mm) |
| Stepper motors |
0.9° NEMA17 (42 mm) XY, 1.8° NEMA23 Z (57 mm) |
| Blast nozzle |
Tungsten carbide Ø6 mm, 55° cone, replaceable liner |
| Pressure pot |
20 L ASME rated 150 psi, pop-off valve, moisture separator |
| Vacuum blower |
1.5 kW regenerative, 180 CFM @ 8 kPa |
6. Depth-Sensor Integration
| Item |
Detail |
| Sensor |
Keyence LJ-V7080 (or LJ-X8060 for higher span) |
| Measurement principle |
2-D laser triangulation (blue laser 405 nm) |
| Z-repeatability |
0.5 µm (lab) → ±0.3 mm derated for dust |
| X-profile width |
8–28 mm depending on model |
| Scan rate |
32 kHz max |
| Output |
RS-422 + analog 4–20 mA |
| Mounting |
Gantry-mounted, 150 mm stand-off |
7. Software Features
- Job Setup Wizard – import STL/DXF, slice into raster toolpath (1 mm hatch) at user-set stand-off
- Auto-Z-Map – pre-scans surface, generates
height_map.csv; used to compute Z_target
- Live Depth Guard – 50 Hz loop that modulates blast valve
- Data Logging – CSV of
x,y,z,blast_state for QA; optional MQTT publish
- Maintenance Counters – abrasive cycles, filter pulse count, hose hours
8. Safety & Compliance
| Standard/Hazard |
Mitigation |
| Dust inhalation |
H13 HEPA, cabinet –50 Pa, differential pressure monitor, OSHA Respirable Dust <1 mg m⁻³ |
| Static discharge |
Bonded hoses & frame to <10 Ω earth stake |
| Noise |
30 mm acoustic foam on cabinet walls, PPE 25 dB earmuffs |
| Pressure vessel |
ASME U-stamp; pop-off valve 150 psi |
| Electrical |
UL-listed PSU, IEC-60950 fusing, e-stop chain |
9. Bill of Materials
| Sub-system |
Est. Cost (USD) |
| Frame & liner |
$400 |
| Motion (rails, belts, steppers) |
$350 |
| Control electronics |
$200 |
| Pressure pot & plumbing |
$200 |
| Compressor (external) |
$1,000 |
| Vacuum blower |
$350 |
| Cyclone + HEPA |
$300 |
| Nozzle + hoses |
$200 |
| Depth sensor (triangulation) |
$6,500 |
| Misc. (glands, wiring, fasteners) |
$300 |
| Total (ex-compressor) |
≈$3,600 |
| Total incl. sensor + compressor |
≈$11k |
10. Testing & Validation
Factory Acceptance
- Jog XY repeatability test (dial indicator): ≤0.05 mm
- Leak test: cabinet holds −50 Pa with doors closed (smoke test)
- Adhesive removal: 0.8 mm acrylic masking over 300×300 mm coupon; residual ≤0.1 mm
- Wood sub-floor: ply veneer 1.2 mm; no breakthrough after full-coverage pass
Safety Compliance
- Dust sampling: 15 cm from exhaust under worst-case load: <0.5 mg m⁻³
- Static continuity: hose-to-earth <10 Ω
Last updated: July 26, 2025