Sourcing10 min read
Contract terms for custom manufacturing: quality, delivery, IP and liability
The clauses that decide what happens when a drawing changes, a batch fails or a tool needs to move, written for buyers who are not lawyers.
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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 19
Browse the full library.
Machining9 min read
Die cast heat sinks and motor housings: fin geometry and thermal contact
The casting rules that decide whether a finned housing moves heat or just looks like it does, from fin draft and base thickness to the machined contact face.
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Machining10 min read
Extruded heat sinks: fin geometry and airflow
Fin spacing, fin height and base thickness are a single decision. Get the airflow wrong and a dense fin stack becomes a hot, heavy block.
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Machining9 min read
Heat sink and casting RFQ checklist: the data that changes the quote
A heat sink request is a thermal brief, a mechanical drawing and a manufacturing route in one. This checklist covers the inputs a supplier needs to quote the part and the process honestly.
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Machining10 min read
Surface roughness Ra and Rz: what the numbers mean on a drawing
Ra and Rz describe the same surface in different ways. This guide covers the definitions, the ratio between them, the drawing callout and the measurement habits that change the result.
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Machining10 min read
Turned copper parts: machinability, tool wear and finish
Copper conducts heat away from the cut, galls on the tool and strings its chips. Here is how alloy, edge geometry and coolant decide the result.
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Machining10 min read
Aluminium extrusions: a profile design guide
How the die, the wall and the void shape the profile, and the tolerance calls that keep a constant cross-section affordable.
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Machining9 min read
Casting defects: cold shuts, flash and shrinkage
Three common casting defects, read by cause and appearance, with the process levers that prevent them and the acceptance questions that stop a defect argument.
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Sourcing10 min read
India vs Eastern Europe for engineered parts: landed cost, lead time and flexibility
A practical comparison for buyers who need a European alternative to an Indian supply base, or the reverse, with the cost lines that decide the answer.
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Machining9 min read
Machined die castings: fixture and datum strategy
How to pick datums, set stock allowance and hold a casting in the fixture so the machined features land where the assembly needs them.
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Machining10 min read
Swiss turning for small copper and brass parts
Why a sliding headstock lathe holds slender parts that a fixed headstock machine cannot, and where the guide bushing stops helping.
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Quality9 min read
ISO 2768 general tolerances explained, with a practical class table
What ISO 2768 covers, how to choose f, m, c or v, and where the standard stops and the drawing has to take over.
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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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