Improving Part Design with Wall Thickness in plastic injection molding

Release time:2020-04-17

To achieve uniform wall thickness in the plastic injection molding , let’s start with the basics:

Recommended wall thickness in injection molding design
Proper wall thickness will reduce the risk of cosmetic defects in plastic parts.
  • Walls in any plastic-molded part should be no less than 40 to 60 percent that of adjacent walls, and all should fit within recommended thickness ranges for the selected material.
  • Part geometries such as long unsupported spans, sharp internal corners, and poorly designed bosses (not the person in the corner office who signs paychecks), should be avoided, regardless of wall thickness.
  • Use ribs for strengthening tall walls where needed.
  • Sharp external corners are fine, but placing a radius on inside corners—part design permitting—makes them stronger and alleviates the stress that creates warp.
  • Bosses should follow molding design guideline rules of properly designed walls of 40-60 percent of the surrounding area to avoid sink.
  • Finally, follow recommendations on draft angles—1 degree of draft per 1 inch of cavity depth is a good rule of thumb—and keep draft consistent throughout the workpiece to prevent internal stresses that lead to warp and curl.

Choose Materials with Wall Thickness 

One of the biggest considerations with wall thickness is which material to use for your project. With literally hundreds of materials to choose from, deciding on the right one can be challenging. You can view available resins grouped by family with recommended wall thickness ranges along with detailed information on material properties, tensile and impact strength, and maximum operating temperatures online.
Here is the materials : 


ABS 0.045 in. - 0.140 in.
Acetal 0.030 in. - 0.120 in.
Acrylic 0.025 in. - 0.500 in.
Liquid crystal polymer 0.030 in. - 0.120 in.
Long-fiber reinforced plastics 0.075 in. - 1.000 in.
Nylon 0.030 in. - 0.115 in.
Polycarbonate 0.040 in. - 0.150 in.
Polyester 0.025 in. - 0.125 in.
Polyethylene 0.030 in. - 0.200 in.
Polyphenylene sulfide 0.020 in. - 0.180 in.
Polypropylene 0.025 in. - 0.150 in.
Polystyrene 0.035 in. - 0.150 in.
Polyurethane 0.080 in. - 0.750 in.

We Chat: Venus
We Chat: Venus
We Chat: Nicole
We Chat: Nicole
We Chat: Phil
We Chat: Phil

Get In Touch or Get A Quote

+86-755-29667661 Moble,What's app, Wechat: (+86) 18675501860