After machining the parts are going for the assembly. The purpose of making mould corrections, engineering change or mold maintenance, it is essentially to know how to assemble the mould in proper procedure. The procedure helps to prevent the mould from possible man-made damage when they assemble the mould. It is also important for the operator in the second mould maker or injection plant to get correct advice and warning quickly.

• Have all the mold plates, inserts, and components in one place ready for assembly.  Have a clean table and two rails to slide plates on.  Tools used must be in good condition and should include allen wrenches, aluminum prybars, rubber/copper/aluminum mallets.
• Cleanliness is critical in mold assembly.  Make sure all plates, inserts, and components are clean and free from grit, debris, and chips.  After you have carefully cleaned all details with a clean, mild solvent and clean towels THEN wipe everything again with your clean, bare hand to remove small grit (Careful NOT to damage sharp edges, parting surfaces, shutoffs, or the cavity finish)
• Install all sub-inserts, gate inserts, core pins, etc. into the primary inserts. Check that all inserts and pins are marked and that they are installed in the correct location and position.

• Mount the B-Plate to the Support Plate
• Install the B-Half insert set, any slide assemblies, and any other B-plate components.  Check that all parts are marked and that they are installed in the correct location and position.
• Insert and grease all ejector pins, ejector sleeves, and ejector blades through the pin retainer plate, support plate, and core inserts.  Install all return pins and springs.  Install and grease any Lifter mechanisms.  Bolt on the Ejector plate.
• Assemble the ejector housing, with support pillars, guided ejection pins, etc.  Guide this assembly through the ejector & other plates and bolt it to the support plate.  Insert any core pins that mount in the bottom clamp plate and fasten their backup plates.  Lubricate the entire assembly.
• Verify that the Slide assembly moves freely, is greased, and that the slide retainer is functioning properly.
• Move the Ejector assembly forward and check if all pins, sleeves, lift cores and all other moving components spin freely. Wiggle to verify correct clearance and that all components move freely
• Check that the ejector plate can use the full length of travel.  Check if the runner & part will clear the core when ejected.
• Mount the A-Plate to the top clamp plate
• Install A-Half insert set, heel blocks, angle pins, and any other A-plate components.  Check that all parts are marked and that they are installed in the correct location and position.
• Install the locating ring & sprue bushing, check that sprue radius, and oriface are the correct size and verify that the sprue bushing is rotation locked and retained
• If the mold features a 3-plate or hot runner system, install them at this stage.
• For Three-Plate molds, verify that all latches function properly, that they latch and release in assembly, and that plate separation is sufficient to let both the part AND the runner drop through.  Also check that all latch dowel pins are secured so as not to come loose during operation.  Lubricate the whole assembly and verify that it moves freely.
• For Hot Runner molds check that all wiring is in a channel, free from damage, and free from possible “pinches” during assembly.  Check continuity all all circuits
• Install all jiffy-connectors with teflon tape or suitable thread sealant and water test.
• Check all limit switches
• Spray with WD-40 and close the assembly
• Verify that the mold has a mold strap and that it is fastened correctly.

At last the assembly mold is inspected by our experts and if the mould achieved our pre-defined quality standards, The mould is ready to go in polishing & hardening.