The cable tie manufacturing is one of the plastic injection molding projects, but is more difficult than the normal one, because:

  • Cable tie is selling in a very low cost, the cable tie manufactures are under huge cost pressure.
  • Cable tie has many different size, each one size request one mold.
  • Cable tie is more difficult in the molding than the normal plastic item.

1. Main problem in nylon cable tie manufacturing

1.1  The mold is blowed to open

cable tie 1
Injection molding machine has not enough clamping force, so that the mold is blowed to open
Solution: check the clamping force setting

1.2  Short shot

cable tie short shot
In the photo, the one in the edge is filled full, but the middle one is short shot, check the following:
mold temperature whether is not even
mold cavities air release design
If one in the edge is not filled full, but the middle one is done, check the following:
mold temperature

1.3 Flashing 

FLASH

Carefully check the corresponding part of the mold

1.4. Bubbles

bubbles on cable tie
Possibility:
Fail to dry the water out from the raw materials,
PA 66 is a relatively complex resin, and absorbs water from air easily. Dry material is the first step to be done. Insufficient dry results in the high temperature water vapour, screw and barrel special for PA will exhaust part of them. But fast injection speed traps air. Poor exhausting design of mold intensifies air trapping.

-design of the screw and barrel

-the molding setting in-correct

1.5  Nylon cable tie gets yellow

turn-yellow-cable-tie
Over-heat, the melt plastic resin is degraded due to the over-heat, please consider: the relation between temperature and cycle time in the article: cable tie production
All the machine operator like to set the machine with high temperature, because it is easy for the molding, because:
  1. Error in machine design
  2. Error in raw material formula
  3. Error in mold design
It is one complicated issue, more information, please check this article: cable tie production

1.6. Brittle

The degrade cable tie is brittle, though the yellow color may be hidden by some chemical.
To inspect cable tie quality, tensile strength is the main point, which is need to check by machine. How to check the cable tie quality, please check this link: how to inspect your cable tie

Important Blogs

onx cable tie

All issues are about cable tie manufacturing: Injection molding machine, mould and raw materials and how they work together?: Cable Tie Production

KF-series-2

What equipment should you buy for cable tie manufacturing and why…        Cable Tie Manufacturing Equipment

mold design

All issues for cable tie mold available,drawing, inserts and more…: Cable Tie Mold – Guide of 2020

cable tie

How to inspect your cable tie quality. Difference between PA66 and PA6 cable tie… : ☞ Cable Tie Sourcing

2. Daily Checking Points for the Factory Management

2.1 Whether the cable tie color is yellow

2.2 Machine situation

2.3 Production record from the machine controlller

controller-data

2.4 When formula changes or applies for the new resin, check the tensile strength by machine