The Troubleshooter: Welcome back, unfilled nylon. How's your mold?


It is another day in the good old Central U.S. My dog Jake has been on his walk this morning and the big truck has delivered a small box full of parts for me to review. As often is the case, there is no note from the molder, but I have seen these particular parts in the past.

The part is an electronic coupling used in the aerospace industry. The material is a flame retardant unfilled nylon and I would guess that the problem is surface appearance. Pretty straight forward and even though appearance is not usually a key issue for parts used in parts normally hidden from view, during installation this might be the one exception I have seen.

Unfilled nylon is one of the materials that needs to have small runners and gates for successful molding. The melt temperature requirements of nylons are pretty straight forward in that they need to be high enough to melt the plastic but not a lot higher because we do not want the material to become degraded.
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