The term "stringiness" is used to refer to a phenomenon where string-line sections of plastic which are formed upon opening of the die adhere to the inside of the die and are transferred to the product during the next shot, resulting in string-line unevenness on the surface of the molded component.
| Appearance |
 |
 |
| Characteristics |
Thin plastic string formed at the tip of a sprue |
Plastic string after transfer to the molded component |
| Cause |
High nozzle temperatures |
| Countermeasures |
- Lower the nozzle temperature; alternatively,make combined use of pull-back and cylinder repetition.
- Strings can be forced to break by increasing the speed of die opening, however, care must be taken as this can result in reduced die service lives for certain die designs (i.e., slides, etc.).
- Use a string-prevent ring (commercially available).
|
| Appearance |
|
| Characteristics |
Thin plastic string formed at the tip of a sprue |
| Cause |
High nozzle temperatures |
| Countermeasures |
- Lower the nozzle temperature; alternatively,make combined use of pull-back and cylinder repetition.
- Strings can be forced to break by increasing the speed of die opening, however, care must be taken as this can result in reduced die service lives for certain die designs (i.e., slides, etc.).
- Use a string-prevent ring (commercially available).
|
| Appearance |
|
| Characteristics |
Plastic string after transfer to the molded component |
| Cause |
High nozzle temperatures |
| Countermeasures |
- Lower the nozzle temperature; alternatively,make combined use of pull-back and cylinder repetition.
- Strings can be forced to break by increasing the speed of die opening, however, care must be taken as this can result in reduced die service lives for certain die designs (i.e., slides, etc.).
- Use a string-prevent ring (commercially available).
|
