CAD Model Simplification
Somewhere in your company, qualified engineers spend entire days deleting fillets. Let’s talk about that.
Model simplification is the invisible full-time job of the CAD world. Component manufacturers simplify thousands of catalog parts by hand so customers get lightweight models that don’t expose internal know-how. Machine builders simplify the over-detailed supplier models they receive, because a screw with modeled threads — placed eight hundred times — brings the top assembly to its knees. Simulation engineers defeature geometry for every analysis, part by part, before any solver can run.
At one component manufacturer we know, an entire department does nothing else. Not design, not development — simplification. Day in, day out, the same sequence: suppress features, remove internals, check the envelope, export, next part. It is the purest form of routine CAD work that exists — rule-governed, repetitive, endless — and it binds exactly the people who are scarcest.
We automate it: rule-based simplification per part family, built on NX automation (NXOpen, synchronous technology, feature recognition), running in batch over whole libraries — with AI assisting in part classification and rule authoring, and with validation checks that prove nothing important was lost and nothing sensitive remains.
// Manual simplification, in numbers
Simplification is rule work. It just was never written as rules.
Watch an experienced engineer simplify a part and you’ll notice something: they barely think. Threads go, internal geometry goes, small fillets and chamfers go, logos and engravings go; mounting interfaces, connector faces and the outer envelope stay — always, for every part of that family. The knowledge is real, but it is not creative judgement. It is a ruleset, executed by hand, thousands of times.
The cost hides in three places. The obvious one is the hours — and where simplification serves a catalog business, those hours scale with every new product family and every variant. The second is latency: customers wait days for a model that a rule could deliver in minutes, and simulation engineers wait on geometry instead of analysing. The third is inconsistency: hand-simplified models differ by author and by daypart, which means IP-critical details survive in some exports and functional interfaces get butchered in others — and nobody systematically checks either.
Written down as executable rules, the same knowledge runs in batch, produces identical results at 2 a.m. and 2 p.m., and — crucially — can be validated: every output model is automatically checked for what must remain (interfaces, envelope, mass properties within tolerance) and what must not (internals, threads, know-how features).
// The same connector housing — full detail vs. delivered model
Validation is the half of the job everyone forgets: every output is checked automatically — mounting interfaces and envelope unchanged, mass properties within tolerance, and provably no internal geometry left in the export.
Four jobs, one automation
The same rule engine serves the four situations where simplification eats the most hours — pick the one that hurts most, the others come almost free:
Customer-facing catalog models
Component manufacturers: every product needs a lightweight, IP-safe download model. Rules generate them per family — consistent, validated, regenerated automatically when the master changes. The department that "only simplifies" gets its engineering back.
Supplier models, tamed
Machine builders: purchased-part models arrive with modeled threads and full internals, multiplied hundreds of times in your assemblies. Batch simplification on import keeps top assemblies fast and your PDM lean.
Simulation-ready geometry
Defeaturing rules per part class and analysis type prepare geometry for meshing — small features out, load-relevant geometry untouched, decided by written rules your simulation engineers own instead of folklore.
Lightweight reps for large assemblies
Envelope and wrap geometry for layout, DMU and factory planning — generated from the same rule base, so a 5,000-part machine opens in seconds where the full model wouldn't open at all.
How the automation works — rules, batch, validation
The pipeline captures what your best simplifier already knows, executes it at machine scale, and adds the step manual work never had: systematic proof that the output is right.
Which family, which rules
- AI-assisted part classification
- Works with native NX & dumb solids
- Family assigned, rules selected
- Unknowns flagged, not guessed
Rules do what hands did
- Threads, fillets, internals removed
- Envelope / wrap where defined
- Interfaces & datums preserved
- NXOpen + synchronous technology
Proof, not hope
- Interfaces & envelope unchanged
- Mass properties within tolerance
- No sensitive geometry in export
- Failures queue for human review
Where it's needed, in batch
- JT, STEP, native — per consumer
- Teamcenter reps & PDM linked
- Auto-regenerate on master change
- Overnight runs over whole libraries
When does simplification automation pay off?
The case scales with part count and repetition. You are a candidate if most of these apply:
- People spend hours every day simplifying models — as a dedicated team or spread invisibly across departments.
- You maintain thousands of catalog parts or variants that need customer-facing models — and IP protection is non-negotiable.
- Top assemblies are slow or unopenable because supplier models carry full detail, hundreds of times over.
- Simulation prep waits on manual defeaturing — and every analyst does it slightly differently.
- Simplified models are inconsistent: what gets removed depends on who did it and when.
- You run Siemens NX (ideally with Teamcenter) and want automation on supported extension points.
What the automation is built on
Supported NX extension points, geometry-level operations for third-party data — and validation as a first-class citizen.
Before and after: a new product family goes live
A component manufacturer releases a new connector family — 340 variants, each needing a customer-facing model. Here is what that release costs on each side of the change:
Before — by hand, by many
- 340 variants × 30–60 min — ~5 person-months
- Market launch waits — or ships with models "to follow"
- Every simplifier decides differently what goes and what stays
- IP check = hoping nobody left the internals in variant 217
- Master changes? The whole ritual starts again
After — rules, batch, proof
- 340 variants simplified in batch — overnight
- Models ready at launch — every variant, every format
- Identical rules, identical results — at 2 a.m. and 2 p.m.
- Validation proves: interfaces kept, internals gone — all 340
- Master changes trigger regeneration — automatically
Why inteliScience — and where the human stays in the loop
Simplification automation is NX engineering at its core: NXOpen batch pipelines, synchronous-technology operations that work even on dumb imported solids, feature and region recognition, Teamcenter integration for reps and regeneration. That is our daily work, built on supported extension points so it survives NX upgrades. The AI layer earns its place where it genuinely helps — classifying parts into families at scale, and drafting simplification rules from examples of your best hand-simplified models, which your engineers then review and release.
Two honest boundaries. First, simulation defeaturing is not universally automatable: what may be removed depends on the load case, and that judgement belongs to your analysts — the automation executes rules per part class and analysis type that they define and own, and flags anything outside the rules instead of guessing. Second, the first weeks of any rollout include human spot-check reviews alongside the automated validation — trust is earned per part family, then the checks scale back to the flagged exceptions. Consistency is precisely what the automation is better at than hands; judgement is what your people keep.
Fixed price — no day rates, no surprises
Simplification Pilot
- Rules workshop with your simplification experts — one part family selected
- Working batch automation for that family, on your NX installation
- 100 real parts processed — results compared against your hand-simplified references
- Validation suite configured: interfaces, mass properties, IP rules
- Measured time comparison + rollout blueprint for the remaining families
6–8 weeks · built on your NX/Teamcenter installation · rules and code are yours, whatever you decide afterwards.
For comparison
The cost of hand work
- Multiple engineer-years spent on suppress-delete-export, every year
- Launches delayed and customers waiting on download models
- And the un-priced risk: internals shipped in one export out of thousands
Frequently asked questions
How is IP protection actually guaranteed — not just hoped?
Supplier models come as dumb STEP solids without features. Can rules work on those?
Will simplified models break our assemblies?
Where do the rules come from — and can our team maintain them?
Can it fully automate simulation defeaturing?
What happens when a master model changes?
Your engineers know exactly which features to delete. They've just done it ten thousand times too often.
Send us five master models and their hand-simplified counterparts — we'll show you the drafted rules and a batch result on your own parts.
Talk to an NX Automation EngineerAlways here to support you – reach out to us with your questions, and we’ll guide you every step of the way.
+40 774 463 429
+40 774 463 429
Romania
info@inteliscience.net
info@inteliscience.net
