Picture a routine ECO (engineering change order): a tab redesigned to reduce snap-fit failure rates the molder already caught during first-article inspection. The molder updates the tool to meet the new spec. The assembly vendor, running a separate facility on its own schedule, doesn’t get the updated print until the change works its way through a second company’s paperwork. In the meantime, a batch of sub-assemblies gets built to a part revision that no longer exists.
Though hypothetical, it serves to describe a familiar risk. When molding and assembly procedures are sourced through multiple suppliers, revisions must travel through the separate companies and their respective QMS before they reach the station required. The result can create scrap that rarely gets traced back to this gap. More often it shows up as a missed ship date or a number nobody wants to explain, while the actual cause sits a few steps upstream.
The cost of splitting molding and assembly across vendors: lag time, reconciliation, and re-work that never quite makes it into the original quote. Turnkey assembly for plastic parts closes the gap. We move the part from the press into assembly in the same building, under the same inspection standard, against the same print.
What “assembly” covers
The term gets used loosely, so a clear scope and definition help. Our in-house assembly spans manual, semi-automated, and fully automated build stations, along with sonic welding, heat staking, and sub-assembly work combining molded components with sourced parts. Kitting is a related but distinct function: the packaging and configuration of finished components into customer-defined sets, running alongside assembly rather than as a separate downstream service. We also handle secondary operations like hot stamping, heat transfer, and pad printing in the same building, feeding directly into whichever step needs a decorated or marked part next. A truly vertically integrated contract manufacturer serves OEMs with incomparable efficiency and reduced opportunity for defects.
Though not every program requires all the services, the clear advantage is being able to draw on whichever mix a part/assembly requires without adding a vendor for each one.
Following a part from press to shipment
When a molded part comes off the press, it may go through an in-process inspection: dimensional checks, weight verification, appearance review, whatever the part calls for. From there, it moves either directly into assembly or first through a secondary operation, depending on the requirement. Once assembly is complete, kitting services configure the finished units according to the customer’s packaging and labeling specifications. The finished kits move into warehousing, where we track them against real production output rather than a forecast, and ship on a schedule tied to customer demand.
By keeping inspection results, lot numbers, and process records connected to the same production activity from receipt through shipment, the number of steps in this sequence is held the most efficient and reliable methods attainable.
Why this is crucial for regulated or high-mix programs
Traceability is an excellent example. When assembly happens at a separate facility, lot control must be re-established, including new receiving records, a new chain of custody, and new sets of documentation to reconcile against the original molding records. By keeping assembly in the same operation, the chain of records stays intact from beginning to end.
CASE STUDY: Our kitting services in the contact lens sector are a useful reference point for what this standard looks like in practice. That work requires 100% accuracy and repeatability on every kit, with lot-level traceability tied directly back to the molding and inspection records that produced the components. Holding this standard consistently across a vendor boundary is difficult. Holding it within one operation is far more manageable, and it’s how we run kitting for that sector every day.
What this replaces
A program that sources molding, secondary operations, assembly, and third-party logistics separately takes on inherent risks. Each vendor has its own lead time, its own communication channel, and its own version of the spec. A revision has to reach all of them individually, and a quality issue has to be traced through each of them. Having to manage multiple suppliers can be costly and challenging to navigate.
We consider complete manufacturing to be turnkey: molding, secondary operations, kitting and assembly, warehousing, and fulfillment running as a single operation rather than a chain of vendors. It replaces the need to work across multiple teams and streamlines the entire manufacturing process for better outcomes.
Capacity behind the work
We run more than 30 injection molding presses ranging from 80 to 950 tons, with integrated robotics on every press. Our assembly capability spans manual, semi-automated, and fully automated lines, so the level of automation we apply to a given program serves the volume and part requirements rather than what happens to be available.
Where to start
If kitting, assembly, or secondary operations are currently split across more than one vendor, mapping the current process against what could move under one roof is a useful next step. We’re happy to review your program(s) and make recommendations to simplify —contact us today.