𝐓𝐨𝐝𝐚𝐲'𝐬 𝐊𝐍𝐎𝐖𝐋𝐄𝐃𝐆𝐄 𝐒𝐡𝐚𝐫𝐞 : 𝐓𝐡𝐞 𝐦𝐨𝐥𝐝 𝐨𝐩𝐞𝐧𝐞𝐝. 𝐓𝐡𝐞 𝐩𝐚𝐫𝐭 𝐥𝐨𝐨𝐤𝐞𝐝 𝐠𝐨𝐨𝐝. 𝐓𝐡𝐞 𝐝𝐢𝐦𝐞𝐧𝐬𝐢𝐨𝐧𝐬 𝐰𝐞𝐫𝐞 𝐜𝐨𝐫𝐫𝐞𝐜𝐭.

𝐓𝐨𝐝𝐚𝐲'𝐬 𝐊𝐍𝐎𝐖𝐋𝐄𝐃𝐆𝐄 𝐒𝐡𝐚𝐫𝐞

𝐓𝐡𝐞 𝐦𝐨𝐥𝐝 𝐨𝐩𝐞𝐧𝐞𝐝.

𝐓𝐡𝐞 𝐩𝐚𝐫𝐭 𝐥𝐨𝐨𝐤𝐞𝐝 𝐠𝐨𝐨𝐝.

𝐓𝐡𝐞 𝐝𝐢𝐦𝐞𝐧𝐬𝐢𝐨𝐧𝐬 𝐰𝐞𝐫𝐞 𝐜𝐨𝐫𝐫𝐞𝐜𝐭.


But near the gate, silver streaks appeared across the surface.

Those are Splay Marks — one of the most common cosmetic defects in injection molding.


Splay marks occur when moisture, trapped gases, contamination, or degraded resin travel with the melt and stretch across the surface during filling. The result is a silver, fan-shaped pattern that becomes highly visible on automotive interior and Class-A surfaces.


Why it happens:

① Moisture in resin

② Excessive injection speed

③ Contamination in the barrel

④ Overheating and resin degradation


How to prevent it:

✓ Dry resin to the specified moisture level

✓ Reduce injection speed when required

✓ Purge the barrel thoroughly during material changes

✓ Optimize barrel temperature settings

✓ Maintain proper back pressure for a homogeneous melt


Splay marks are not a surface problem.

They are evidence of what happened inside the barrel before the plastic ever reached the mold.

Dry the resin. Control the temperature. Respect the process.


💬 Have you ever traced splay marks back to a dryer issue, humidity change, or material contamination? Share your experience below.


#InjectionMolding #SplayMarks #SilverStreaks #PlasticDesign #DFM

#ResinDrying #MoistureControl


source : #IMTechnologies


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