AIM Processing Small Plastic Parts Blog

It takes some time and effort to establish a good working relationship with a small plastic part injection molder. As a result, you may be reluctant to move on to a different provider, even if the current relationship starts to deteriorate.

A number of questions will likely come to mind — things like:

• What are the signs that it’s time to leave?
• What are we risking if we decide to stay?
• If we choose to leave, what is involved in moving our processes to a new injection molding shop?

It’s not uncommon for a small plastic injection molded part to be expected to hold up under a large load. One of the ways to strengthen a part is by adding one or more “ribs” to the design. Ribs are thin protrusions that extend perpendicular from a wall or plane to provide added stiffness and strength.

If you have a new plastic project in mind, one of the first things you’re likely to wonder is, “What will it cost to create this small plastic part?” In order to answer your question, an injection molder will need to know a little more. Though you may not have precise answers, even educated guesses can help shape an accurate quote so you can explore your options.

When it comes to the angles used in the plastic part design of injection molded parts, you’d be surprised to learn what a big difference as little as half a degree can make. In particular, the draft of a part can play a major role in everything from how easy it is to eject the part from the mold to how smooth the surface of the finished part is.

The process of plastic injection molding can produce the perfect parts for your needs quickly and cost effectively. However, as with any manufacturing process, there are certain “gotchas” that can cause less than optimal results. Below are five design guidelines you should follow to help ensure that your production runs deliver an outstanding finished product.

The concept of the one-stop shop as it applies to plastic injection molding goes back many decades. Historically, injection molders sought to deliver more value to their customers by handling every aspect of a project in-house, beginning with designing and developing molds.

In plastic injection molding, one of the most important aspects of the mold design is how and where it is gated. The “gate” is the opening in a mold through which the molten plastic is injected into the final part.  It is the boundary between part and scrap. The location, size, and shape of the gate can have a significant effect on everything from the structural integrity to the visual appearance of a finished piece.

It would make sense that the thicker the walls of a part are, the stronger it is. However, that’s not always the case. That statement is based on the assumption that the walls have a uniform density. Unfortunately, thicker walls have the potential for voids or hollow spaces within them. This means you may not be getting the consistent depth, or the strength, you were counting on.

Insert molding, or more accurately “plastic injection insert molding,” is a process in which viscous plastic is injected into a mold around one or more items. When the plastic cools and hardens, the result is an integrated assembly that incorporates these “inserts.” The items can be metal, ceramic, or any other type of material that can withstand the heat of the melted plastic and the pressure with which it is injected into the mold.

Plastic injection molding is a very cost-effective way to produce high-quality parts. Even so, there are a number of things you can do to save even more money on a project without sacrificing anything in the finished product.