Defect |
In-DepthClick on Article Below: |
QuickFix
|
Splay |
Splay article |
Longer dry time, Lower/ Higher barrel heats, slower filling(velocities), higher
mold temperatures, check barrel and hopper throughput, check melt temperature to
MSDS |
Short/underfill |
Short article |
Higher heats, more pressure, faster filling, slower end of fill, improve
venting, larger shot size, check peak/ hold pressure |
Sink |
Sink Article |
Higher pressure, larger shot, faster fill over affected area, longer
cure time, gate seal study, check watering to schematic, check for mold "hot spots",
longer hold time |
Stringing |
Stringing article |
Confirm nozzle tip orifice and type,, lower nozzle temperature, increase/
decrease decompression after rotation position, lower drp temperatures (hot runner) |
Gate Blush |
Blush Article |
Raise cut-off, slower end of fill, lower heats, profile velocities,
check high pressure/ fill time limits, compare actuals to processing variables
from previous runs, gate seal study |
Voids/ Bubbles |
Voids Link |
Slower/ faster fill in affected area, lower/higher heats (barrel/mold), higher/lower pack pressures or times |
Stress/ Cracking |
cracking article |
Lower pressure, faster fill in affected area,inspect for tooling issue,longer cure time, slower mold open speed |
Drag Marks |
Drag Article |
Slower mold open, less pressure, inspect for tool damage, longer cure, hold time study, decouple process
to assure using proper shot size, profile velocities |
Color Swirls |
Swirl Article |
lower/higher heats, slower recovery, higher/lower back
pressure, confirm proper melt temperature, check watering |
Pin Push Marks |
Pin Mark Article |
Lower ejection pressure, slower ejection speed, more cure time, faster
fill, decouple molding process, inspect mold for damage, reduce pack pressure |
Flow Lines |
Flowline article |
Higher/lower cut-off, faster/slower velocities, higher/lower temperatures
(barrel/mold), profile velocities, decouple molding process, confirm melt temperature
, measure mold temperature to assure consistent temperatures,check water to schematic |
Burns/ Gas Trap |
Burn article |
Slower fill in affected area,lower barrel temp, higher mold temp,
check water flow, decouple molding process, profile velocities, check melt
temperature, gate seal study |
Jetting/ Worming |
Jetting Article |
Slower fill in affected area,higher mold temp, check watering to schematic,
compare molding variables to those recorded on previous runs, measure melt
temperature, profile velocities |
Cold Slug |
Cold Slug Article |
Increase/ decrease decompression after rotation position, slower beginning velocities,
confirm tip orifice size and type, Inspect tool for burrs, consider cold slug wells,
lower nozzle temperature, lower/ raise drop temperatures (hot runner) |
Problem |
Cause
|
Solutions |
Ejectors won't retract |
dry tool lacking grease, broken ejector pin, water off,broken spring,
galling |
Inspect mold for above problems, check water set up, pull mold in halves
when applicable |
Slide sticking; mold with slides won't lock up |
galled slide surface,burrs, dry slide surface, tool overheating |
inspect tool for above conditions, review water set up, pull mold in
halves if applicable |
Sink/pin push |
galled surface, tool overheating, cure time too low, Mold open speeds
and pressures too high |
check for above conditions, and review velocities for slow filling
over these areas |
Stringing |
tip too large for bushing, hot runner drop temps too high, low
decompressure after rotation setup (position)> |
Install smaller tip, lower drop heats, increase decompression after
rotation (position), add screw delay time to compensate for long cure time
(screw should recover prior to cure time setpoint) |
Parting line flash |
Drop hold/ pack to 0; assess part in shortshot state and see if flash
still exists |
flash on shortshot condition reflects tool problem..blue parting line
and inspect for proper seal off |
Tool binds during ejection |
too few knockouts, galling, broken ejector pin, improper grease, poor water
setup |
pyrometer tool heat schematic, inspect for above conditions, pull mold in
halves if unable to retract to zero position |
Stress/cracking |
Galled surfaces, overpacking, slow fill, poor cure time, poor watering
|
Lower pressure, faster fill in affected area,inspect for tooling issue,
longer cure, inspect for tooling issues listed above |
Drag marks |
broken spring, galled surfaces,overpacking, early mold open,
too much on ejection speed/ pressure fast open break, parting line burr,
poor watering |
inspect for above conditions and respond per the situation |
Color swirls |
tool related: hot runner temps too high/low, velocity too high for
tooling(sheer burn)application, tip not matched to bushing, cracked check ring,
heater band/ thermocouple failure
|
check melt temp, inspect for above failures/issues |
Pin push marks |
pin mark article |
lower ejection pressure, slower ejection speed, more cure time,
faster fill |
Flow lines |
tool related: hot runner temps too high/low, velocity too high for tooling
(sheer burn) application, tip not matched to bushing, cracked check ring, heater band/
thermocouple failure |
higher/lower cut-off, faster/slower velocities, higher/lower temperatures
(barrel/mold)inspect heater bands/thermocouples (hot runner),inspect for improper
setups listed above |
Burns |
tool related: hot runner temps too high/low, velocity too high for tooling
(sheer burn)
application, tip not matched to bushing, cracked check ring, heater band/ thermocouple
failure |
slower fill affected area,lower barrel temp, higher mold temp,check water
flow |
Cold slug |
cold slug article |
increase decompression after position, increase/decrease drop temp,
slower beginning velocities, confirm tip size |
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