TPE overmolding of a power tool handle

SKU: PMI633 Category:

TPE overmolding of a power tool handle

This is a power tool handle done by TPE overmolding on a substrate of PA6+GF30.

TPE overmolding substrate close view
There are small grooves on the substrate locating near the edge of the TPE area, the purpose is quite straightforward, which is to create mechanical interlocks to help improve the bonding strength.

These parts are produced in regular horizontal injection molding machines. First, the substrates are molded, then after a few days, the substrates will be used for the overmolding with the second mold. This process is done manually.
The substrates shall be kept clean, free from dirt, debris, oil, and mold release agents before being used. However, we do not heat the substrates, even in winter. We can still get a good adhesion strength.
As you can see, the overmolding is quite nicely done, there are almost no peeling, frayings, flashes and delamination found.

Part specification

Cavity materialH13, P20, 718H, S136, 2738, 1.2344, etc.
Product materialTPE, PA6+GF30
Cavity numbersSingle or multiple
Mold structureCold runner, hot runner
Mold baseStandard, self-made.
Lead time30 to 45 days

Mold cost: $10,000

2 molds are required, one for the substrate, the other for the TPE over-molding. Each mold has 2 cavities

The mold material is 718H.

A short video: