Pad printing
Ink transferred by a silicone pad onto curved and recessed surfaces.
Pad printingProcesses
Injection Molding Processes and Secondary Operations
Pick the molding process and the finishing steps your part needs. Each page explains one process; the quote covers the tool, the parts, and the operations together.
Processes
Start with the molding process, then add the operations
This hub routes to one page per process. It does not repeat them.
Every program starts with plastic injection molding in a hardened steel tool. Some parts add a second material or a metal insert in the mold. Many add a print, a foil mark, or a weld after molding.
Open the page for the step you are planning. When you are ready, list every operation in one quote request so tooling, parts, and finishing are reviewed together.
Further down, the process guides explain specialty routes such as gas assist, stack molds, and metal injection molding. They are engineering references for deciding whether a part needs them.
Secondary operations
Marking and joining after molding
Operations run on finished parts from the production tool.
Hot stamping
Heated die and foil for metallic or solid color marks.
Hot stampingUltrasonic welding
Vibration welded joints between molded plastic parts.
Ultrasonic weldingAll secondary operations
Painting, silk screening, laser marking, assembly, and packaging.
All secondary operationsMolding processes
Processes that happen in the mold
Service pages for each molding route.
Plastic injection molding
The core process behind every program.
Plastic injection moldingInsert molding
Metal or pre-made components molded in place.
Insert moldingOvermolding
A second material molded over a substrate.
OvermoldingFamily injection molding
Several different parts from one tool.
Family injection moldingHigh volume injection molding
Multi cavity tools for repeating demand.
High volume injection moldingMulti material and in mold
More than one material, or a finish added in the mold
How second shots, skins, labels, and films end up inside one molded part.
Two shot molding
Two materials molded in one cycle on one press.
Two shot moldingMulti shot molding
Three or more materials, and when that is too many.
Multi shot moldingCo-injection molding
A skin and a hidden core from one gate.
Co-injection moldingRotary platen molding
Turning the mold between shots.
Rotary platen moldingCore back molding
Pulling a core to open room for the next shot.
Core back moldingIn mold labeling
A printed label fused to the part as it fills.
In mold labelingIn mold decorating
Printed film transferred or bonded in the mold.
In mold decoratingIn mold electronics
Printed circuits formed and molded into a surface.
In mold electronicsStructure and scale
Hollow, foamed, very thin, or very small parts
Processes that change how the melt fills or what ends up inside the part.
Gas assist molding
Gas cores out thick sections from the inside.
Gas assist moldingStructural foam molding
Large, stiff parts with a foamed core.
Structural foam moldingMuCell foam molding
Microcellular foam to cut sink and warp.
MuCell foam moldingThin wall molding
Long flows through thin sections at speed.
Thin wall moldingMicro molding
Parts too small for a standard screw to meter.
Micro moldingMold types
Molds built around one specific problem
More parts per press, alternating parts, or threads that have to turn out.
Stack molds
Two parting lines in one press.
Stack moldsTandem molds
Two levels that open in turn.
Tandem moldsUnscrewing molds
Cores that rotate threads out of the part.
Unscrewing moldsAfter molding
Joining, finishing, and treating molded parts
Operations beyond the standard list above, explained for engineering review.
Heat staking
Melting a post to hold another part in place.
Heat stakingLaser welding
Welding through a clear top part.
Laser weldingSolvent bonding
Softening two surfaces so they fuse.
Solvent bondingVapor polishing
Solvent vapor that smooths and clears a surface.
Vapor polishingAnnealing
Relaxing molded in stress with controlled heat.
AnnealingEMI shielding coating
Conductive layers inside plastic housings.
EMI shielding coatingAutomated assembly cells
Feeding, joining, and checking parts in one station.
Automated assembly cellsOther materials
Rubber, thermoset, metal, and ceramic molding
How these routes work, and when a molded thermoplastic part can replace them.
Liquid silicone rubber
Two part silicone cured in a hot mold.
Liquid silicone rubberThermoset molding
Phenolic, BMC, and epoxy cured in the mold.
Thermoset moldingMetal injection molding
Molded powder sintered into metal.
Metal injection moldingCeramic injection molding
Zirconia and alumina parts from powder.
Ceramic injection moldingDecide between options
Process comparisons
When two routes could both work.
Overmolding vs two shot
Two ways to put two materials on one part.
Overmolding vs two shotInsert molding vs post mold assembly
Mold the insert in or install it after ejection.
Insert molding vs post mold assemblyUltrasonic welding vs adhesive
Choosing a joint for molded halves.
Ultrasonic welding vs adhesivePainting vs molded in color
Where the part color should come from.
Painting vs molded in colorOne quote
Operations on one quote versus a separate finisher
Keeping molding and finishing together shortens the handoffs.
Separate finishing vendor
- Parts ship out for printing, stamping, or welding
- Design issues surface after the tool is built
- Two schedules and two quality records
NetProto quote
- Tool, parts, and operations reviewed together in DFM
- Joint and print areas checked before steel is cut
- One project record from quote to delivery
FAQ
Common questions
Which processes does NetProto offer?
Plastic injection molding, insert molding, overmolding, family and multi cavity molds, and export molds, plus secondary operations such as painting, silk screening, pad printing, hot stamping, laser marking, ultrasonic welding, assembly, and packaging.
Can I add secondary operations after the first order?
Yes. Operations run on finished parts, so they can be added to a later order from the same tool. Designing for them early avoids tool changes.
Is every process guide on this page a NetProto service?
No. The molding processes and secondary operations listed first are quoted with the part. The process guides explain other routes so you can judge whether a part needs them. If you are unsure which route fits, describe the requirement in the quote request.
Next step
Quote the tool, the parts, and the operations together
Upload CAD and list every operation in one request. NetProto manufacturing is ISO 9001 certified.