This week my team and I built a 3-axis CNC engraver for drypoint printmaking. My specific contribution was in the enclosure design and manufacturing: from the structural aluminum tubing (cutting, drilling, painting) to the infinite-screw shafts and rod preparation, the laser-cut and table-saw machine bed, and the full fabrication and assembly of the plywood enclosure box.
Week Assignment
Design and build a machine that includes mechanism, actuation, automation, function, and a user interface.
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Aluminum Tubing
Cut, deburred, drilled, primed & painted the square aluminum profiles for the structural frame.
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Lead Screws & Rods
Cut infinite-screw shafts and guide rods to length; beveled ends on the grinder.
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Machine Bed
Laser-cut and table-saw cuts for the CNC work surface.
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Enclosure Box
Full design in Fusion 360, CNC routing, assembly and finishing of the plywood cabinet.
Process 01
Aluminum Square Tubing
The main structural frame uses square aluminum profiles that needed to be cut to precise lengths, deburred, drilled for fasteners, primed, and painted. Below is the full process from raw stock to finished painted pieces.
01 — Tools & Measurement Setup Each profile was measured and marked to the required lengths (300 mm and 190 mm) based on assembly drawings.
// tools used to cut & measure the aluminum profile
02 — Cutting the Profiles The tube was secured against the fence and cut in a single controlled pass to avoid deflection and keep a clean edge.
// clamping the tube against the fence
03 — Deburring the Cut Edges A file was used to remove burrs and smooth the cut face flush after every cut.
// visible burr right after cutting → clean after filing
04 — Drilling the Fastener Holes The drill press made precise, perpendicular holes for the M4 fasteners that join the profiles to the 3D-printed corner joints.
// bench drill press setup — tube clamped in vise
05 — Sanding & Priming All profiles were lightly sanded to remove surface oxidation and improve paint adhesion. A metal primer was applied first.
// profiles after sanding and primer coat applied
05 (cont.) — Final Paint Finish A metallic spray paint was applied over the primer for a clean, corrosion-resistant finish.
// final metallic paint finish on all profiles
Process 02
Lead Screws & Guide Rods
The motion transmission system relies on lead screws (infinite screws / tornillos sin fin) and smooth steel guide rods, all cut to the lengths defined in the Bill of Materials. The ends were beveled on a bench grinder for clean, burr-free insertion into the mounted bearings and couplers.
01 — Cutting Lead Screws with a Hacksaw A hacksaw was the right tool for cutting the threaded rod stock cleanly without stripping the thread pitch. Each screw was marked, clamped in a vise, and cut to the required length.
// hacksaw and lead screw stock
02 — Positioning Guide Rod in the Band Saw The smooth steel guide rods were cut using the bench band saw. The rod was positioned carefully against the fence for a square end face.
// guide rod set up in the band saw
03 — Beveling Ends on the Bench Grinder After cutting, each shaft end was touched to the bench grinder wheel to create a clean bevel. This removes sharp edges and allows the rod or screw to seat correctly inside bearings and couplers without catching or causing misalignment.
// beveled rod end — bench grinder finish
Why Bevel?
Beveling is a small but critical step: un-chamfered shaft ends can prevent proper seating in linear bearings and cause premature wear on the bearing races.
Process 03
Machine Bed
The machine bed provides the flat work surface where metal plates are held during engraving. It was fabricated from MDF and plywood using a combination of laser cutting and table-saw cuts, then drilled for mounting to the aluminum frame.
01 — Laser Cutting Some components of the bed were cut on the laser cutter for precise dimensions and clean edges. Parameters were set based on material thickness to achieve a full cut without excessive charring.
// laser cutter settings used for the bed panels
02 — Table Saw Cuts Straight rip and cross-cuts for the larger bed panels were made on the table saw — faster and more efficient than the laser for full-width straight cuts on thicker plywood stock.
// rip cuts on the table saw for the bed panels
Fabrication Summary
Operation
Tool
Material
Notes
Precision panel cuts
Laser cutter
MDF / thin ply
Used for complex shapes & mounting holes
Straight rip & cross cuts
Table saw
Plywood
Fast production cuts, square fence guide
Mounting hole drilling
Drill press
Both
M4 clearance holes to attach to frame
Process 04
Enclosure Design & Fabrication
The enclosure protects the CNC machine, stores tools in a dedicated drawer, and provides clear acrylic windows for visibility during operation. Below is the complete workflow from sketch to finished cabinet.
01 — Sketches & Concept Initial hand-drawn sketches explored the form, proportions, and functional requirements: a lift-up front door, a bottom drawer, and acrylic windows.
// first concept sketch — exploring proportions
02 — 3D Model in Fusion 360 A parametric hybrid model was built to iterate on panel thicknesses, joint tolerances, and cut layouts before any material was touched.
// final Fusion 360 render
03 — DXF Export & VCarve Configuration Panels were exported as DXFs from Fusion 360 and loaded into VCarve to set up the toolpaths, cut depth, and pass strategy.
// VCarve toolpath and cutting configuration
04 — CNC Router Cutting Panels requiring pocketing or precise joint geometry were cut on the CNC router. Straight panel cuts were made on the table saw to speed up production.
// CNC router cutting the enclosure panels
Issue Encountered: One panel came out with an incorrect toolpath — a pocket was cut in the wrong location. The panel was repaired with wood filler, allowed to cure, then sanded flush before assembly.
05 — Sanding & Surface Prep All panels were sanded with 120-grit paper to remove machine marks, smooth edges, and create a clean glue surface.
// sanding panels after routing — 120 grit
06 — Acrylic Windows — Laser Cut & Bonded Side and top acrylic window panels were laser-cut, test-fit into the routed pockets, then bonded using clear epoxy adhesive.
// laser cutting acrylic window panels
07 — Box Assembly The base box was assembled using corner clamps while wood glue cured, then fastened with wood screws. Where gaps formed, additional glue was applied and clamped overnight.
// full box assembled with panels and clamps
08 — Drawer Rails, Hinges & Hardware Drawer slides were installed for smooth alignment. Piano hinges were fitted along the full width of the lift-up front door. All hardware was drilled with the drill press for consistent depth.
// installing the drawer rails
Screw Length Issue: The default screws included with the piano hinges were too long and punched through the 9 mm plywood. They were replaced with shorter M3 screws, and exit holes were filled and sanded flush.
09 — Final Assembly An internal mounting platform was installed to seat the CNC at the correct height with clearance below for cable routing. The CNC machine was placed inside and the final assembly was inspected.
// CNC mounting platform inside the enclosure
Finished Enclosure
// finished enclosure with CNC machine installed
Reflection
Learning Outcomes
This week was a hands-on deep-dive into fabrication beyond digital making — working with raw materials, real tools, and the tolerances that only reveal themselves once you start building. Here are the key lessons from my contribution to the enclosure.
⚠ Challenge
9 mm Plywood Is Tricky Thin 9 mm plywood warps easily, especially after routing. Several panels bowed slightly, causing gaps during assembly. Clamping strategy and glue selection matter a lot at this thickness.
⚠ Challenge
Panel Separation During Assembly Some panels separated after initial glue-up, requiring re-clamping. The combination of thin stock and pocketed joints meant the glue surface area was sometimes too small.
⚠ Challenge
Screw Length Mismatch on Hinges The default piano hinge screws punched through the 9 mm plywood. Each screw had to be swapped for shorter ones, and exit holes required filling and sanding.
↗ What Could Be Improved
Electronics Integration & Cable Management Cable lengths and routing paths should be designed in parallel with the enclosure, not after. Cables from the PCBs were too short to route neatly.
✦ Future Improvement
Discrete & Hidden Joinery In a future version I would use pocket-hole screws covered by plugs, or dado/rabbet joints — so no fastener heads or filler patches are visible on the surface.
✓ Key Learning
Multi-Process Manufacturing Managing one project across four fabrication processes (laser, CNC routing, table saw, drill press) taught me that tolerances stack — a 0.5 mm cut error on the laser can cause misalignment downstream.
Conclusion
The enclosure turned out functional and solid, but the process made very clear that thin plywood requires more attention to glue surface area, clamping time, and hardware selection than thicker stock. In a future iteration I would move to 12 mm panels, use hidden joinery, and design the electronics integration from day one.
