The short answer A two-plate mould opens at one parting line, gates at the edge and ejects the part with its runner. A three-plate mould adds a floating runner plate and a second parting line, so a pin-point gate can sit anywhere on the face and the runner drops away unaided, for 15 to 40 percent more tool cost. One plate changes everything The two-plate tool is the default because it is the s...

The short answer Most moulded parts land between 1.5 and 3.0 mm: ABS 1.5 to 3.5 mm, PC 1.5 to 3.0, 30 percent glass-filled PA66 1.2 to 3.0. Keep the wall uniform, taper any change at 3:1, and hold ribs at 40 to 60 percent of the wall. Thin walls fail on flow length, thick ones on sinks. Why the wall is the first number you fix Wall thickness sets three things at once, and only one of them is s...

The short answer Most moulded walls need 1 to 2 degrees of draft per side, ribs and bosses 0.5 to 1 degree. Add 1 to 1.5 degrees for every 0.025 mm of texture depth, which takes a typical 0.06 to 0.08 mm grain to 3 to 5 degrees. Core-side features need more than cavity-side ones. What draft actually does during ejection A cooling part shrinks. On the male side of the tool, the core, it shrinks...

The short answer LSR molding supplies medical tubing and seals, baby nipples and pacifiers, kitchenware gaskets, automotive and EV battery seals, wearable and keypad seals, and industrial O-rings. These parts share three traits: thin walls from 0.3 to 3 mm, a service window from -60 to 200 degrees Celsius, and volumes above about 25,000 a year. Six product families, and the trait they share Li...

The short answer LSR brings four things medical and food parts need: it can be supplied with USP Class VI and ISO 10993 test data, it meets FDA 21 CFR 177.2600 and EU 10/2011 food-contact rules, it survives steam, EtO and gamma sterilization, and it works from -60 to 200 degrees Celsius with low compression set. What "medical grade" actually means: standards, not claims The phrase medical grad...

The short answer Pick the overmold for its chemistry, not its colour: ABS, PC, PC-ABS and nylon bond chemically to matched TPE grades at 100 to 300 newtons of peel strength, while PP needs a modified grade and POM, HDPE and PEEK bond only mechanically. Then check melt temperature, hardness and wall thickness. Chemistry decides first: polar bonds, non-polar does not Overmolding works by bonding...

The short answer Overmolding is used for soft-touch grips on tools and appliances, sealed connectors and integrated gaskets, vibration-damping mounts, encapsulated electronics and dual-durometer parts. It replaces a glued or snap-fitted assembly with one bonded component, typically cutting assembly cost by around 30 percent and holding soft layers from 0.8 to 3 mm. Six application families and...

The short answer Two-shot injection molding uses one machine with two injection units and a rotating, indexing or core-back mold. The first shot forms a rigid substrate in cavity A, the mold moves the partly cooled part to cavity B, and the second shot bonds a second colour or a soft elastomer onto it, with no manual handling. What a two-shot machine actually does A two-shot press is not a sta...

The short answer Bi-colour molding pays off for consumer electronics because it replaces two or three secondary operations with one cycle. Soft-touch grips, scratch-proof colour, sealed gaskets and light-guide windows are formed in the mold, typically cutting 15 to 30 percent from unit cost and removing the assembly steps where delamination, misalignment and paint wear begin. Where the value s...

The short answer Insert molding improves strength by locking metal into plastic rather than pressing it in. Molten plastic at 40 to 140 megapascals fills the knurls and undercuts, then shrinks 0.5 to 2 percent as it cools and grips the insert, giving a pull-out force two to four times that of an insert fitted after moulding. The interlock is mechanical, not adhesive An insert designed for mold...

The short answer Insert molding places a metal or plastic insert on a locating pin in the tool and floods molten plastic around it, so the insert becomes part of the moulding. Choose it over post-moulding assembly when the joint must resist repeated torque and vibration, close a leak path, or hold at volumes above about 20,000 parts a year. What insert molding is, step by step Insert molding i...

The short answer Cut injection molding cost by fixing the part design before the tool is cut. Keep walls uniform at 1.5 to 3 mm, pull 1 to 3 degrees of draft, radius every corner at half the wall, and remove undercuts needing side actions. These changes typically cut tooling 20 to 40 percent and cycle time 15 to 25 percent. Where injection molding cost is actually decided Most of the cost of a...

The short answer Above roughly 10,000 parts a year the question stops being about technology and becomes a question about tooling phases. A printed prototype proves shape; an aluminum bridge tool proves the molded part in production resin; a hardened steel tool proves mass production. Each handoff changes shrink, gate position, cooling and tolerance, and each is where launches lose weeks. Why ...

The short answer Minimum order quantity is not a supplier policy, it is an amortization question. A soft aluminum tool costing 1,500 to 5,000 US dollars becomes practical at 50 to 200 parts; a standard P20 steel tool at 8,000 to 18,000 dollars needs 500 to 1,000; a hardened precision tool at 15,000 to 35,000 dollars or more needs 2,000 to 5,000. MOQ is arithmetic, not house rules The tooling h...

The short answer Warping and sink marks are volumetric problems. Amorphous resins like ABS and polycarbonate shrink 0.3 to 0.8 percent; semi-crystalline PP, POM and nylon shrink 1.0 to 3.0 percent and sink and twist more. Uniform walls, ribs at 40 to 60 percent of the wall, cooling balanced within 5 degrees Celsius, and correct hold pressure fix most of it. Two defects, one mechanism A sink ma...

The short answer Unit price is set by five things: resin, machine time, tooling amortization, labor and overhead, and scrap. Material typically runs 30 to 55 percent of part cost and machine time 20 to 35 percent, while tooling amortization starts at dollars per part and falls below ten cents once volume passes 100,000. What actually goes into a quoted unit price A molded part price is not one...