I am using an HDPE IM grade having an MFI of about 8g/10min (@2.16kg). The specimens seem to have a flow marks on the surface, near the gate. The flow marks resemble a sort of melt fracture at that point and vary with the shape of the specimen. Larger specimens have minimal jet marks while smaller dumbell shaped specimens have it more pronounced. (image attached).

I have tried varying the injection speed, pressure and the dosing shot. However it has reduced the marks but has not eradicated them. Moreover, there are numerous parameters to consider and changing too many at a time has not led to any conclusive steps to troubleshoot the issue.

Any help would be appreciated.

P.S. i have consulted several 'troubleshooting guides' but their methods did not help. changing the gate location/type is not an option for me currently

Thanks