Guidelines for Fill time of painted plastic parts

[ErikFoltz5821]

Hello,

I'm writing today to see if anyone can help with guidelines for gate sizing of plastic parts that will be painted post-molding. I remember during my training and professional experience that you need to fill plastic parts that will be painted later more slowly than normal. I was always told that a maximum bulk shear rate of 15,000s-1 was the preferred limit for such a case (painting or plating). However, I have never seen any publications/liturature to support or disprove this threshold.

I'm sure like all things there are different levels for different materials, but I'm wondering what other use for a guideline.

Any thoughts out there?

Thanks,

Erik