Injection Molding: the route, the tolerances it holds, materials and design tips, with an indicative cost. One of 56 processes in the free finder.
PolymerFamily
+/-0.05mmTypical tol.
5Route steps
342Parts in finder
Plastic injection moulding injects molten polymer into a cooled steel mould under pressure; it solidifies and ejects as a finished part in seconds.
At a glance
When to use it, and when not
Best for
High-volume plastic parts of almost any shape, from housings to medical devices.
Watch for
High mould cost, draft and uniform-wall rules, and sink or warp on thick sections.
Step by step
The typical route
Raw material to finished part. Steps vary with material, volume and tolerance; this is the free route from the finder.
Dry resin
Dry and feed the resin.
Tooling - Tolerance - Lead -
Inject
Inject into the mold, hold and cool.
Tooling Mold Tolerance - Lead -
Eject
Eject the part.
Tooling - Tolerance - Lead -
Degate
Trim the gate/runner.
Tooling - Tolerance - Lead -
Inspect
Check dimensions and cosmetics.
Tooling - Tolerance - Lead -
Precision
Tolerances it can hold
TYPICAL TOLERANCE IT CAN HOLD
Where this process typically lands. Tighter is possible with extra operations like grinding, at higher cost.
Materials
Materials it suits
Grade
Why it suits this
ABS
Tough, cheap, easy
Polypropylene (PP)
Living hinges, chemical
Glass-filled nylon (PA-GF)
Stiff, strong
Design
Design tips
A few general pointers for Injection Molding. The full, part-specific DFM list is in the dossier.
Thick or uneven walls.Even them, core out thick bosses.
No draft.Add >=1 deg draft.
Cost
What it costs
The qty-1 figure is really the mold (2k to 50k+ USD) amortised; above ~5k parts it is pennies of resin.
PER-PART COST vs VOLUME
Per-part cost drops as volume spreads tooling and setup over more parts. The exact figures for your part at your volume, in your currency, are in the dossier.
MODEL EST.
$2390 to 6695per part at 1 off
A rough ballpark only. The dossier gives should-cost at your exact volume and currency, with the full breakdown.
GET THE FULL DOSSIER
Everything you need to quote and source it
The free route above is yours. To actually put a number on this process and buy it well:
Should-cost at your exact volume in 12 currencies, with the material, processing, tooling and overhead breakdown
Who to source from, typical MOQ and lead time, and the exact RFQ checklist to send
A quote checker that tells you if a supplier quote is fair, and the red flags to watch
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Plastic injection moulding injects molten polymer into a cooled steel mould under pressure; it solidifies and ejects as a finished part in seconds. The typical route is: Dry resin; Inject; Eject; Degate; Inspect. High-volume plastic parts of almost any shape, from housings to medical devices.
What does Injection Molding cost per part?
It depends on size, tolerance and volume. As a rough ballpark it starts around $2390 to 6695 per part at low volume and falls with quantity. The dossier gives should-cost at your exact volume and currency. Model estimates, not quotes.
What tolerance can Injection Molding hold?
Typically about +/-0.05 mm, tighter with extra finishing operations at higher cost.
What materials suit Injection Molding?
Common choices are ABS (Tough, cheap, easy); Polypropylene (PP) (Living hinges, chemical); Glass-filled nylon (PA-GF) (Stiff, strong).
See the exact route and should-cost for your part
The free finder maps your part to its process and full route. Pro adds should-cost at your volume, sourcing and an RFQ draft.
