Injection Moulding: Where Tolerance Lives
A thread, a seal groove, a multi-part collar — none of these can be blown. Injection is the process that holds a dimension, and the one that costs most per part.
What We Run
Closures, caps, collars, bases, droppers, thick-wall PETG bodies and every component of a multi-part assembly. Machines from small tonnage for a 20 mm cap to larger presses for a 200 mm collar.
Tolerance, Honestly
±0.05 mm on a machined steel feature, ±0.1 mm on a moulded thread, ±0.15 mm on a height across a 200 mm part. Those numbers are why a seal groove is designed at 1.5–1.6 mm deep rather than "about 1.5".
A blow-moulded thread moves more, which is why a bottle that must seal repeatedly is often injection moulded even though it costs more per piece.
Wall and Cycle
A thick wall is a slow wall: heat has to leave through the plastic, so a 2.5 mm PETG body runs a longer cycle than a 1.8 mm one. That is the real reason a thick-wall pack is expensive — not the resin alone.
What to Send
A drawing with the thread callout, the seal groove section and the wall. For a multi-part pack, the assembly section as well — the tolerance stack is decided here, not in the blow mould.
Have an Injection Part?
Send the section — we return the DFM note in 3–5 days.