Plastics10 min read
Material selection for MCB, MCCB and ACB housings
How the duty of a miniature, moulded case or air circuit breaker decides the housing polymer, the filler and the evidence you need before approval.
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Topic hub
Plastics and assemblies
Electrical housings carry three jobs at once: structure, insulation and assembly. These guides cover wall sections, ribs, draft, material choice and the tolerances that keep a moulded part fitting.
Guides in this topic, page 2
Plastics9 min read
Moulding defects: short shots, sink, flash and warpage
A defect signature guide for moulded parts, with the first check, the process cause and the tool or design change that fixes each one.
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Plastics10 min read
PEEK and high-temperature mouldings: temperature, cost and process
When a housing or an insulator really needs a high-temperature polymer, what the process demands, and where a cheaper material will do the same job.
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Plastics8 min read
Plastic part cost drivers: material, cycle, cavitation and yield
A moulded part price is four numbers working together. Change the wall, the cavity count or the scrap rate and the same drawing can move by 30% before any negotiation starts.
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Plastics10 min read
Sourcing assemblies from India: supplier models and ramp
Four ways an Indian supplier can build an assembly, the sub tier risk behind each one, and the ramp plan that keeps a launch from stalling.
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Plastics9 min read
Assembly RFQ checklist: BOM, drawings, test and packing
An assembly enquiry needs more than a drawing set. Here is the information that lets a supplier price labour, test and logistics without guessing.
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Plastics10 min read
Assembly traceability and serialisation: lot, serial and test records
How to design a traceability chain that can answer which parts went into a unit, what happened at each station and where the unit went, without slowing the line.
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Plastics9 min read
Moulding tolerances: what to expect
Realistic tolerance bands for injection moulded parts, the four things that move a dimension after the tool is cut, and how to write a drawing the moulder can hold.
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Plastics8 min read
Plastic material certificates and RoHS: what belongs in the pack
A resin datasheet is not a compliance document, and a RoHS statement is not a material certificate. Here is the paperwork that proves a moulded part is what the drawing says.
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Plastics8 min read
Prototype moulding: 3D printed parts vs aluminium tools
How to choose between a printed sample and a soft aluminium tool when the prototype has to prove fit, material behaviour or a production process.
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Plastics10 min read
Assembly FAI and PPAP: the pack for a multi part build
How to run a first article on an assembly, link the BOM to the ballooned drawing, and build a PPAP pack that proves the process, not just the parts.
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Plastics9 min read
Gate location and weld lines
How the gate position sets the fill pattern, where weld lines land, and what each gate type leaves on the part.
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