2.2 KiB
Sag-Mesh Plane v0.1 — Certificate of Central Compromise (CCC)
File: sag-mesh-plane-certificate-central-compromise.md
1. Design Name Sag-Mesh Plane v0.1
2. Central Compromise The plane is formed from a deliberately under-spec PLA+ mesh grid created in OpenSCAD. The print alternates Y-then-X line layers, with each line made from two nozzle passes (≈0.8 mm total width using a 0.4 mm nozzle). After each layer, the nozzle is raised 0.2 mm and the orientation switches. This creates a grid with 2–3 mm spacing, prone to sagging and weak fusing. Stiffness and flatness are only achieved by filling the mesh with rapid-set cement.
3. Purpose of Compromise To create a rigid, flat panel at extremely low cost by combining a weak, sagging printed lattice with an abundant, globally available fill material.
4. Good-Enough Justification
- Cement provides bulk stiffness; the PLA mesh provides geometry and a mechanical key.
- The alternating Y/X pattern reduces directional bias.
- Produces flat-enough panels for jigs, shims, or tool bases.
- Not structural, not weatherproof, not heat-resistant — but cheap and repeatable.
5. Print Sequence (Explicit)
- Layer 1 (Z=0): Print Y-oriented lines, each line = 2 passes (≈0.8 mm), spacing 2–3 mm.
- Raise Z by 0.2 mm.
- Layer 2: Print X-oriented lines, same spacing and passes.
- Raise Z by 0.2 mm.
- Repeat Y/X alternation until desired thickness (3–5 cycles typical).
6. Replicability Proof
- Anchor COTS: rapid-set cement mortar (globally available).
- Alternates: Plaster of Paris / Perfect Cast for lighter builds; Portland cement for heavier.
7. Substitution Map (Optional)
- Heavier/stronger: Portland cement.
- Lighter/weaker: Perfect Cast plaster.
- Mesh reinforcement: mosquito net or screen.
8. Failure Envelope
- Visible cracking or edge chipping.
- PLA creep under heat.
- Panel not suitable for load-bearing or outdoor use.
9. Statement of Intent This design deliberately embraces a weak mesh and flawed print process, relying on cheap cement fill to achieve utility. It is an explicit trade of durability and precision for cost, abundance, and accessibility.