Easy Solutions to Splay Caused by Bleeding

Undesired bleed out in injection molding can be caused by—and lead to—a number of problems. One of the most common injection molding defects caused by bleeding is splay, which is often the result of an over-lubricated mold

Syn-Lube™, which breaks down differently than other greases and helps eliminate bleeding, when applied properly, could be the solution to any issues you’re experiencing with splay.

What is Splay?

Silver or white streaks appearing on the surface of the part often indicate splay in injection molding. Several other defects, like scuffs, flow lines, surface scratches, delamination from contamination and flaking, can resemble splay, so it’s important to determine the cause of the streaks as the first step in troubleshooting.

When the cause is from bleeding, you’re probably looking at splay, potentially from a mold with too much lubricant or grease.

How Bleeding Can Cause Splay

If the splay shows up immediately after getting the mold from the tool room, it’s likely the result of too much grease being applied to the mold. When a mold is over-lubricated, grease from the lifters and ejector pins may bleed onto the surface of the part, which then leave the silver or white streaks indicative of splay.

Sometimes, grease can get trapped in the mold inserts, which also leads to bleeding out.

More is not better when it comes to lubricating a mold, so it’s important to know how to properly apply a grease (see bottom of the page for instructions).

Using Syn-Lube to Mitigate Bleeding

The proper application of any lubricant is essential. Even better: the proper application of Syn-Lube. Syn-Lube high-performance synthetic grease lasts 10 times longer than competitor products and also doesn’t break down like other greases.

Other greases turn to oil at higher temperatures, which can then lead to bleeding into mold cavities. Syn-Lube is a full synthetic, food-grade grease that can be applied very thinly and will not break down with heat like other greases.

If you’re having issues with splay caused by bleed out in injection molding, try Syn-Lube. Applied properly, it will last longer and resist breakdown into potential bleeding.