Quality9 min read
ISO 2768-f vs ISO 2768-m: choosing a class without over-tolerancing
How much the class actually changes, where fine tolerances earn their cost, and why medium is the better default for most custom parts.
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Sourcing notes for custom parts
Drawings, tooling, quality and landed cost, from the team that runs the programmes.
All guides, page 12
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Quality10 min read
Pull test and weld shear test: fixtures, samples and records
Two tests that look alike on a report and answer different questions. How to set the load axis, choose the sample and record a result that survives an audit.
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Quality8 min read
RoHS and REACH declarations: what they cover and what they leave out
Two regimes, three common declaration types and the checks that show whether a document describes the part that will actually ship.
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Plastics9 min read
CTI and dielectric strength of moulding materials
Tracking and breakdown are different failures with different tests. Here is how to read the numbers and turn them into creepage, clearance and a material call.
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Plastics9 min read
Glow wire testing for electrical plastics
GWFI, GWIT and the glow wire test explained: what each one measures, how the results are reported and which requirement belongs on the drawing.
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Plastics9 min read
Packaging and kitting for assemblies: damage, presentation and cost
How to pack an assembly so it arrives undamaged, present it at the line without extra handling, and stop packaging from quietly becoming the largest cost per unit.
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Plastics9 min read
Plastic housing FAI and PPAP: the evidence pack for a moulded part
What a first article inspection and a production part approval pack should contain for a moulded housing, including the plastic-specific evidence that a generic checklist misses.
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Plastics8 min read
Welded assemblies: resistance, ultrasonic and laser
Three welding methods, three different material and joint rules. The method has to match the material, the access and the joint you can actually design.
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Wireforms9 min read
Wireform prototype approval checklist
Eight checks that turn a working sample into an approved production reference, with the evidence to keep for each one.
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Plastics9 min read
Design for assembly: 10 rules that cut build cost
Ten rules for parts that go together without a fight, and the assembly cost each one attacks.
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Plastics9 min read
Flame retardant plastics and UL 94
What the UL 94 ratings actually measure, how thickness and colour change the result, and how to specify a flame retardant grade without paying for a rating you cannot use.
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Plastics9 min read
Plastic part measurement and GD&T: fixtures, temperature and datums
Why a moulded part measured like a machined part gives the wrong answer, and how to set the condition, the fixture and the datum scheme before the first article.
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Go from reading to checking
The guides are built around the same questions as the free tools. Size a busbar, check an ISO 2768 callout, build a first article report or compare landed cost.
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