Design for manufacture · undercuts and inserts
Undercuts, internal features and inserts, worked out before tooling.
Flexible moulds let us release undercuts that rigid tools can't. Steel tools need cores, side actions or a redesign. The review works out which your part needs, and whether a small change makes it simpler.
The detail
DFM: undercuts and inserts, at group level.
Undercuts are where silicone tooling earns its keep. A hand-made or cast silicone mould can peel off shapes a steel tool would lock onto. But once volume pushes the job to compression or injection, the same undercut needs a mechanism — and mechanisms add cost and risk.
We review undercuts and inserts together because they often interact. An insert that sits across a parting line, or an undercut that traps an insert, is worth catching on paper.
Back to Design for manufacture, across five moulding routes.
What's involved
Six parts of the work.
Flexible release
Which undercuts a silicone tool can peel off without damage.
Cores and side actions
What a rigid tool would need, and what it adds.
Design-out options
Small changes that remove an undercut without changing function.
Insert placement
Inserts located so they're held and don't cross parting lines.
Internal passages
Bores, channels and hollows, with core removal planned.
Route impact
Where an undercut decides the route, we tell you plainly.
How it runs
Four steps, in order.
- 01
Feature review
Undercuts and inserts identified on the model.
- 02
Options
Tool mechanism or design change, compared.
- 03
Agree
You choose which changes to accept.
- 04
Design frozen
Tool built to the agreed version.
Is it right for you?
An honest fit check.
A good fit when
- Your part has hooks, lips, threads or re-entrant features
- You need metal or plastic inserts in a moulded part
- A quote came back high because of tool mechanisms
- You're moving a flexible-tool part onto a rigid tool
Probably not the answer when
- Hand-made one-offs where the silicone tool handles undercuts already
- Designs that can't change and already have a proven tool
- Non-elastomer parts
At a glance
The idea in a picture.
One enquiry, the right team
- 01One enquiryTell us what you need
- 02Right divisionWe bring in the specialists
- 03One quoteCovering every part of the job
- 04Named contactOne person keeps it moving
- 05DeliveredMoulds, parts or both
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FAQs
Common questions.
Can silicone moulds handle any undercut?
Many, not all. Deep or closed undercuts can tear a tool. We'll say which are safe.
Do side actions add much?
They add tool complexity. We'll show you the difference on the quote.
Can you mould in my inserts?
Yes — see our silicone and metal insert service.
Related
The rest of this service.
Where the tool splits, and how the part comes out.
Draft and parting lines decide whether a part releases cleanly, where the witness line shows and how long the tool…
How many cavities, and how to make them all fill the same.
More cavities per shot lowers unit cost — if every cavity fills, cures and releases the same. The layout review sets…
Design for manufacture, across five moulding routes.
A part designed for one process doesn't necessarily suit another. Our DFM review covers all five moulding routes we run…
The group
Delivered across the group
This work is coordinated by TCI Group and carried out by whichever of the four divisions suits your part.
Get in touch
Not sure which division? Tell us what you're making.
Send us a sketch, a photograph, or a paragraph. We'll come back with the right division, the right route, and an honest sense of what it will take.
Real people, a real workshop
You deal with the people who make it.
No call centre and no middlemen. When you contact TCI Group, you speak to the team who design, build and check your mould.
- A real Warwickshire workshopUnit 15, Waterloo Park, Bidford-on-Avon, Alcester B50 4JG.
- Real people on the phoneCall the team on 01789 224228, Monday to Friday.
- The same team on every jobDesign, production and aftercare come from the people you see here.
- Five brands, one teamMoulds, culinary, construction and contract products, all run from Bidford-on-Avon. See the divisions.
Thomas LaneManaging Director
George PrestonDesign & Project Manager
Kelly BallingerHead of Partnerships
Jim AndertonProduction Manager
TheodoreEmployee Welfare