Today's KNOWLEDGE Share: Acetal in Hot Runners

Today's KNOWLEDGE Share

💡 Acetal in Hot Runners – What’s Your Experience?

🗣️ My recent post on regrind prompted some great points from industry professionals, so I thought it would be a good opportunity to get your thoughts on another topic that I’ve debated over the years.

🧩 Over the years I’ve run quite a few tools with Acetal (POM) in hot runners. While they can absolutely produce parts to specification, I’ve often found they bring their own set of challenges compared to other polymers.

⚡ For example, I’ve had to slow injection speeds right down to avoid visual defects. This can make the transition between switchover and holding pressure values quite dramatic, as Acetal typically requires heavy packing to achieve consistent results.

🌡️ I’ve also noticed that hot runner temperatures often need to be dropped much lower than you might expect to prevent degradation, particularly if there are dead spots or areas where material tends to hang up.

✅ It’s not that it can’t be done, but in my experience it takes more care.

💬 I’d love to hear from others: what’s been your experience processing Acetal in hot runners?

source : James Hayward