INJECTION MOLDSToth Mold/Die Inc. Since 1982
Hot Runner Molds and Three-Plate Molds
HOT RUNNER MOLDS are usually made for high production because of the added expense. Rule of thumb for adding a hot runner increases the mold cost approximately 30-50%. However, using a hot runner has big advantages. It eliminates the need to cut and trim a gate which causes a reduction of material since there is no runner. Hot runner molds are a must when there is a multi-cavity injection mold with high cavitations such as a 64 to 128 cavity mold. Another big advantage is there is no need to adjust the cycle time to allow trimming and degating.
Is a Hot Runner Mold Right for Me?
A hot runner mold consists of a standard mold construction as if it were an injection mold with standard gating. A second or third plate is added to the “A” side of the mold behind the “A” plate or top clamp plate if one exists. This plate is a manifold plate and it houses the gate nozzles, cartridge heaters, thermocouples and other components. The hot runner manifold plate is usually purchased from a company that specializes in hot runner applications. Years ago, these manifold plates were built in-house and the success of them working well was very slim. Today, with all the new technology, very few, if any, are still made in house of the injection mold maker. The injection molding company must have experience in running hot runner molds and must have temperature controllers for the different zones and nozzles. On a four cavity mold there are usually eight separate zones of heaters that must be controlled and sometimes there are also cartridge heaters to heat the other plates of the mold.
Do you currently have a hot runner mold that you need to have run?
If you are looking for an injection mold shop to run your hot runner mold, the first question to ask them is if they have a temperature controller with enough zones to control all the zones that the mold has. One of the big drawbacks of a hot runner mold is color changes. For color changes, sometimes the manifold plate must be taken apart and cleaned in addition to the nozzles. This usually means the injection molding company will require a minimum quantity for a production run or the rate for color changes can be costly.
Toth Mold/Die Inc. can provide all your hot runner mold needs.
THREE-PLATE MOLDS are used for automatic degating and center gating on multi-cavity molds. Three-plate molds are less expensive than hot runner molds and there is also a runner left over. An advantage to gating with a three-plate mold eliminates the need for cutting the gate off the part. Some multi-cavity molds must have a center gate on each part. A three-plate mold is the most economical way to achieve this. The best thing to do is to find an injection mold making shop that can guide you in the right direction in producing your injection mold.
Toth Mold/Die Inc. has the expertise and experience to provide this guidance to you.
Contact us today to discuss your next project!