Author Question: Explain how both undercuring and overcuring can cause part cracking on removal from the compression ... (Read 7 times)

bclement10 · **on:** Aug 19, 2018

Explain how both undercuring and overcuring can cause part cracking on removal from the compression molding process.

What will be an ideal response?

Question 2

Discuss the differences in resin orientation that would be expected in a part made by transfer molding and a part made by injection molding.

What will be an ideal response?

quynhmickitran · **Reply #1 on:** Aug 19, 2018

Answer to Question 1

Overcuring can result in brittle parts that crack when the ejection system pushes the part out of the mold. Overcured parts may also stick to the mold. Undercuring can produce cracked parts because the strength of the part is lower than desired and may not be sufficient to withstand the pressures of ejection.

Answer to Question 2

The part made by transfer molding will be made from a relatively low viscosity thermoset resin whereas the part made from injection molding will be made from a much more viscous melted thermoplastic resin. Therefore, the orientation of the molecules that results from flow within the runner system and in the mold is expected to be much higher in the injection molded part.