Step 5 · Decide

Choose the materials methodically

Compare the whole system: weight, assembly, maintenance, cost, availability and safety.

Choose for a use, not for a reputation

Saying "aluminium is light" or "steel is strong" is not enough. The result depends on the thickness, the shape, the joints, the quality available and the making tools.

ChatGPT can organise the comparison. The final characteristics must come from supplier documents, suitable calculations and tests.

Four families to compare

Plywood

Easy to cut, modify and repair. It can be attractive for a prototype or an accessible build. You need to study the weight, moisture, edge wear and the hold of the fixings.

Aluminium

Can offer a good ratio of mass to stiffness depending on the design. It calls for suitable joining processes, care with the edges and an often higher budget.

Steel

Allows sturdy structures and common joints in an equipped workshop. Weight, corrosion, welds and surface protection must be taken into account.

Panels and technical polymers

Often resist moisture well and can be easy to clean. Stiffness, creep, joints, repairability and local availability must be checked.

Compare the whole system

CriterionUseful question
MassWhat will the weight of the complete structure be, joints included?
StiffnessDoes the top stay stable enough during the planned tasks?
AssemblyAre the tools and skills needed actually available?
RepairCan a damaged part be replaced simply?
EnvironmentAre moisture, dust, impacts, temperature and the products used compatible?
CostDoes the price include offcuts, hardware, finish and transport?
SafetyAre edges, splinters, pinch points, stability and failure behaviour under control?
Request to copy

Compare these materials for the attached concept. Use only the data I provide or clearly cited sources. Separate the raw material's properties from the finished structure's performance. End with the missing data and the tests needed before any decision.

Prepare the questions for the supplier

  • What exact reference is offered?
  • What thickness and what tolerances?
  • What weight per panel, profile or metre?
  • What joining processes are recommended?
  • What use limits or precautions are stated?
  • Are the technical documents and certificates needed available?
  • What lead time, minimum order and delivered cost?

Avoid the single choice too early

The prototype can mix several materials: a metal structure, replaceable panels, a wooden top, polymer guards. The best architecture is not necessarily "all aluminium" or "all wood".

Essential validation: loads, thickness, joints and safety devices must not be decided from a general ChatGPT answer. Have the design checked when the risk or the use requires it.

Choice sheet

Part concerned: top, frame, drawer, leg or handle.

Function: what the part must ensure.

Options compared: exact references.

Verified data: suppliers, measurements and tests.

Option chosen for prototype: a provisional decision.

Condition for final validation: test or opinion required.