https://www.avient.com/resource-center?document_type=59&page=37
The focus for this study was to develop thermoplastic elastomer compounds that would overmold onto substrates made from Nylon (PA), Polycarbonate (PC), Acrylonitrile-butadiene-styrene (ABS), and PC/ABS alloys
Whether you’re designing fittings for PC-connected systems, or for smartphone-installed devices, we can help you craft a game-changing experience for the user.
https://www.avient.com/sites/default/files/2020-10/2020-gravi-tech-design-guide-.pdf
CHAPTER 3 | PART DESIGN GUIDELINES
Wall Thickness (mm)
C
o
o
li
n
g
T
im
(
S
c
)
40
35
30
25
20
15
10
0 1 2 3 4
ABS
PC
Nylon 6/6
Figure 2 - Designing for Wall Thickness Changes
Bad
Better
Recommended
Recommended
Poor
High Stress
Ideal
Figure 3 - Internal and External
Radius Guidelines
.5W Min
Inside Rad + W
Poor
High Volume
FIGURE 1 - Wall thickness vs. cooling
time of various plastics
FIGURE 2 - Designing for
wall thickness changes
FIGURE 3 - Internal and external
radius guidelines
Design Guide 9
RIB DESIGN GUIDELINES
The minimum distance ribs should be spaced is
three times the nominal wall thickness (3W).
Solvent
Solvents soften surfaces of plastic (plastic
must be soluble)—best for amorphous or
low crystalline plastics, such as ABS, acrylic,
cellulosic, PC, PS, PPO, and vinyls.
Venting Guidelines by Resin
• PC: .001"–.002" depth & .250" width
• PC/PSU: .002"–.003" depth & .250" width
• PES: .003"–.004" depth & .250" width
• PEI: .001"–.003" depth & .250" width
• PP: .001"–.002" depth & .250" width
• ABS: .0015"–.0025" depth & .250" width
• PEEK: .002"–.004" depth & .250" width
FIGURE 40 - Venting Guidelines
Vent Groove
Vent Land
Vent
FIGURE 44 - Venting guidelines
FIGURE 43 - Venting areas
20 Gravi-Tech
CHAPTER 5 | PROCESS OPTIMIZATION
Process optimization ensures a quality process and
minimizes cycle time.
