
Engineering guide
How to Assess an Obsolete Component Replacement Properly
A practical engineering method for replacing obsolete electronic and electrical components without reducing a design decision to a part-number match.
Read in-depth article →Engineering insights
Detailed articles on product definition, CAD development, component obsolescence, manufacturing drawings, prototyping and production tooling—written for engineers, manufacturers and SME product teams.
Technical library
Each guide focuses on the engineering reasoning behind the work: what to check, where projects fail, and how to turn an open problem into a controlled deliverable.

Engineering guide
A practical engineering method for replacing obsolete electronic and electrical components without reducing a design decision to a part-number match.
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Engineering guide
A detailed guide to turning 3D geometry into an unambiguous manufacturing definition: datums, tolerances, materials, finishes, notes and revision control.
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Engineering guide
How to decide whether a production jig or fixture should be 3D printed, machined or hybrid—and how to design additive tooling that survives real use.
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Engineering guide
A structured product-development workflow for turning an idea, sketch or legacy part into controlled CAD and a prototype that answers the right engineering questions.
Read in-depth article →Why these topics
For small manufacturers and product teams, the difficult work is usually at the interfaces: defining what a part must do, controlling what production is allowed to vary, finding a defensible replacement for an obsolete component, or deciding whether a prototype has actually answered the design question.
The articles are deliberately detailed so they can be used as working references rather than short promotional posts.
D&L Design Engineering provides fixed-scope CAD, component engineering, manufacturing drawing, prototype and production-support work for UK SMEs.
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