A sheet metal gauge chart can help interpret a thickness description, but a folding machine inquiry should also state the material and thickness in explicit units. Identify the chart or convention being used, confirm the supplier's material specification, and discuss the actual working length and profile.
The purpose is to remove ambiguity from an equipment request. A gauge label on its own is not a complete description of the stock that the machine must form.
Compare common gauge references by material
The following selected nominal values, in millimetres, are from Metal Supermarkets' sheet metal gauge chart. They illustrate why the material column matters. Actual stock thickness is subject to tolerances; confirm the supplier's specification.
- 18. Standard steel mm: 1.214; Stainless steel mm: 1.270; Galvanized steel mm: 1.310
- 20. Standard steel mm: 0.911; Stainless steel mm: 0.9525; Galvanized steel mm: 1.005
- 22. Standard steel mm: 0.759; Stainless steel mm: 0.7937; Galvanized steel mm: 0.853
These are material references, not ARTITECT capacity ratings. Submit the actual material and working conditions for a machine assessment.
Translate the label into an agreed material description
Ask the stock supplier for the material grade, nominal thickness and relevant tolerance information. Record thickness in millimetres or inches and retain the original gauge description if the business uses one. Do not mix values from unidentified charts into a quotation comparison.
For coated or finished stock, ask how thickness is defined in the material documents. Provide the finish requirements as a separate field so the machine discussion includes surface handling as well as nominal capacity.
Keep the chart separate from machine capacity
Manufacturer specifications show why the material context matters. KNUTH's folding-machine overview describes different machine types and applications; capacity must be assessed against the actual machine and workpiece.
Avoid writing “must fold this gauge” without the working length, material and profile. Ask the machinery supplier to identify the conditions attached to its proposal. A headline thickness should not be extrapolated across every metal, length and geometry.
Build a clear material schedule
- Material. Suggested information for the inquiry: Grade and supplier specification
- Thickness. Suggested information for the inquiry: Nominal value in explicit units and relevant tolerance
- Original notation. Suggested information for the inquiry: Gauge label and identified chart, if used
- Part geometry. Suggested information for the inquiry: Drawing, fold length, returns and special features
- Surface. Suggested information for the inquiry: Coating or finish and agreed appearance criteria
- Production task. Suggested information for the inquiry: Batch mix, handling needs and first-article checks
Use one line per materially different production requirement. This gives the supplier a way to flag a condition that needs a different setup or further trial.
Carry thickness into the flat-pattern review
Thickness is also an input to unfolding. Autodesk's sheet metal rule reference groups thickness, bend radius and K factor within sheet metal rules.
Before releasing blanks, ask programming and production to confirm they are using the same material definition. If the stock changes, review both the forming setup and the unfolding rule. Treat this as a revision check, not an automatic instruction to alter a single number until a part fits.
Ask for a trial tied to the material schedule
ARTITECT describes CNC material thickness adjustment on its machine functions page. Discuss the proposed configuration using the actual schedule. Ask what material and representative profile should be supplied for evaluation, and agree the dimensions and appearance to inspect.
Questions about gauge charts
Can I use the same gauge value for every material?
No. Use the relevant material column and confirm the stock's documented thickness before purchasing equipment or material.
Should I remove gauge notation from my records?
You can retain it, but pair it with explicit thickness units and the material definition.
Does nominal thickness establish folding capacity?
It is one requirement. Submit working length, material and geometry for the specific machine assessment.
What happens when the material batch changes?
Review the supplier's documents and your agreed incoming and first-article checks.
What should I send ARTITECT?
Send the material schedule and profile drawings. Ask for a configuration discussion and written confirmation of the conditions covered by the proposal.