Glass-Filled Nylon with Regrind

Since the regrind has variable sized pieces,
additional drying time may be necessary to ensure the thicker chunks are fully
dried. The regrind process results in irregular-sized pieces which have different cross sections.


Question:  Most of our parts use an industrial grade resin ( recycled PA with GF) and often with 20% of  regrind resin. This means that the viscosity can vary significantly as well as the size of the “pellet”. Any recommendation when molding with recycled PAGF resin?

My ResponseSince the regrind has variable sized pieces,
additional drying time may be necessary to ensure the thicker chunks are fully
dried. You should always take measures to reduce the shear applied to this
material. This will reduce the degree of polymer chain and additive degradation
which takes place in the barrel. If the parts have thin walls, you will have to use higher 2nd stage packing pressures than you currently use, this can be more than the transfer pressure for many molds (assuming a 1st stage short shot is used).

-Andy  

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