Systemizing mold maintenance is based on establishing consistency in repairs required (performance) and repairs performed (maintenance). Cleaning is another area where individual techniques (freelancing) greatly affect mold reliability, part quality and the tooling budget. To be cost-effective, mold cleaning must be performed: […]
Mold cleaning is a process where major maintenance bottlenecks often occur because molds are pulled faster than they can be cleaned and made production-ready. I have visited plants where molds waiting to be cleaned line hallways and toolrooms, taking up valuable bench space. Many times, in order to meet production demands, molds get reset dirty [...]
To prevent this from happening, both the spindle and tool are blasted with compressed air each time a tool is changed. In some cases, the spindle and tool are cleaned automatically by the compressed air service installed in the machine while other machines’ spindles are cleaned manually. […]
The answer is to simply reduce the temperature differences when welding. There are three things you should do to get a perfectly invisible weld: […]
Once the mold is packed, you have to be sure that you have good cooling. Cooling is about 80 percent of the cycle, making challenging the mold cooling system very important. Checking each cooling channel to ensure that proper flow is achieved, in addition to developing a mold surface map of temperatures is key. [...]
It also is important during the time you are packing the mold, to observe whether or not the gate is sealed. This is an area that causes a lot of trouble with new tools. They are absolutely sure—based on the long hold time they have used in the process—that the gates are sealed, [...]
After filling you must pressurize the mold to get a good imprint of the cavity to minimize the effects of cooling. Short shots, sinks, voids and dimensional variations in parts are caused because of insufficient packing pressure in the mold cavities. […]
As part of a rigorous mold tryout, it is essential to instrument a mold to see what is going on inside the mold. […]
With the proper temperatures set, the mold must be filled as fast as consistently possible. This means that the mold should be able to be filled to at least 90 percent of the injection rate of the production molding machine without adverse effects. […]
It starts out with the temperatures of the plastic. The temperature of the plastic coming out of the molding machine should be right down the middle of the manufacturer’s spec. If you can run a mold here, […]