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Free engineering tools
Hand-built calculators and references we use every day at CADfinity. No sign-up, no ads — just answers.
Reverse Engineering Advisor
Upload part photos or an STL/OBJ scan — get a full RE plan plus mesh→STEP conversion guidance.
AI
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GD&T Expert Advisor
AI feedback on tolerance choices per ASME Y14.5.
AI
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Surface Finish Converter
Ra ↔ Rz ↔ RMS ↔ µin ↔ µm with ISO grade reference.
Reference
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Bolt Torque & Preload
Tightening torque, clamp load and yield % for ISO/SAE bolts.
Mechanical
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Thread & Tap Drill Chart
Searchable ISO Metric, UN, NPT, BSPP/BSPT and Whitworth reference.
Reference
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Material Weight & Cost
Mass and cost for steel, aluminum, titanium, plastics, SLS.
Calculator
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3D Scanner Selector
5-step guided quiz that recommends the right scanner.
AIWizard
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Gear Calculator
Spur, helical, internal, rack, bevel, worm — forward design and reverse-engineering from measurements.
Calculator
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Oil Seal & Sealing Standards
ISO 6194 / DIN 3760 rotary, AS568 + ISO 3601 O-rings, V-rings, ISO 5597 hydraulic.
Reference
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