A medical molder just submitted this interesting question… PL In our attempts to optimize, we are often asked by the tooling engineers to put different temps across sections of the tool. An example would be operating core temps at lower temps than the rest of the tool. We try to keep the tool at the […]
Category Archives
Plastics Technology
Safety Glasses on the Production Floor
I was recently asked a question which has been debated for many years… Jennifer What is the proper rule for safety glasses? Some say they are not always needed, others say they should be work at all times, what is your opinion? My Response Before I relate my opinion, I first want to bring up three […]
Can High Clamp Tonnage Cause Flash?
In a recent seminar, I received this interesting question… Participant Can high clamp tonnage actually cause flash? My Response Yes, it actually can. High Clamp Tonnage can block the vents, causing gases to become trapped in the mold during 1st stage injection. Although, these gasses most often heat and cause burning or short shots… these gasses can […]
Rules for a DIII Process
A frequent blogger asked this question the other day… MJ I know, the rules for DII process as follows: • A process that uses one injection speed to fill – whenever possible • The mold fills 95 to 98 percent full during first stage • All cavities are short shot during first stage • […]
The Affect Of Screw Diameter On Shear Rate
One of our customers brought up this question… Jim M. How does shear rate vary for the same fill rate going from a small screw to a large screw? The volumetric flow rate being the same of course, but is there a difference in shear rate caused by the barrel / screw size differences? My […]