Hot Melt Troubleshooting

Explore comprehensive hot melt troubleshooting tips and solutions below.

Whether you’re dealing with adhesive issues, equipment malfunctions, or application challenges, our expert insights will guide you toward efficient problem resolution. 

Click sections to expand

POOR ADHESION
 
PROBABLE CAUSE

  • The temperature is too low.
  • Insufficient adhesive amount.
  • Coated or difficult substrate.
  • Poor compression.

SUGGESTED SOLUTIONS
 

  • Increase temperature.
  • Increase glue line.
  • Select a proper adhesive.
  • Check compression.
POP OPENS

Adhesive on 1 substrate

PROBABLE CAUSE

  • Insufficient glue amount.
  • The temperature is too low.

SUGGESTED SOLUTIONS

  • Increase the pressure or nozzle size.
  • Increase the temperature.

 

Adhesive on 2 substrates

PROBABLE CAUSE –Adhesive on 2 substrates

  • Too much adhesive.
  • Poor compression.
  • Shifting during compression.
  • The temperature is too high.

SUGGESTED SOLUTIONS

  • Decrease the glue application.
  • Increase the compression time.
  • Correct the compression.
  • Decrease the temperature.
GELLING
 
PROBABLE CAUSE

  • Overheating.
  • Mixing incompatible adhesives.
  • Poor stability of hot melt.

SUGGESTED SOLUTIONS
 

  • Drain the system and lower the temperature.
  • Check with the hot melt supplier.
  • Select a different hot melt.
CHARRING
 
PROBABLE CAUSE

  • The temperature is too high.
  • Hot melt is charring on side walls.
  • Air oxidizing hot melt.
  • Poor stability of hot melt.

SUGGESTED SOLUTIONS
 

  • Lower the temperature in the tank.
  • Keep the tank full.
  • Close the lid, and consider a nitrogen blanket.
  • Decrease the temperature.
STRINGING / DROOLING
 

PROBABLE CAUSE

  • The temperature is too low.
  • The pressure is too low.
  • The nozzle is too far from the substrate.
  • Poor shut-off of the nozzle.

SUGGESTED SOLUTIONS
 

  • Increase pot temperature.
  • Increase pressure.
  • Adjust nozzle.
  • Repair or replace the spool valve.
SMOKING
 
PROBABLE CAUSE

  • The temperature is too high.
  • Poor stability of the hot melt.

SUGGESTED SOLUTIONS
 

  • Lower the temperature.
  • Select a different hot melt.
UNEVEN FLOW FROM NOZZLES
 
PROBABLE CAUSE

  • Nozzle clogged.
  • Remote nozzles in multiple nozzle set-up may be affected by pressure drop.

SUGGESTED SOLUTIONS
 

  • Clean or repair the nozzle and check the filters.
  • Increase the temperature or pressure slightly.
  • Install larger nozzle orifices on the remote nozzle.

Need additional help?

Call Technical Support At: 317-210-7170

Other Resources

Whether you’re dealing with adhesive issues, equipment malfunctions, or application challenges, our expert insights will guide you toward efficient problem resolution. 

s

Poor Adhesion

PROBABLE CAUSE

  • The temperature is too low.
  • Insufficient adhesive amount.
  • Coated or difficult substrate.
  • Poor compression.

SUGGESTED SOLUTIONS

  • Increase the temperature.
  • Increase the glue line/dot/pattern size.
  • Select a proper adhesive.
  • Check the compression.
s

Gelling

 
PROBABLE CAUSE

  • Overheating.
  • Mixing incompatible adhesives.
  • Poor stability of hot melt.

SUGGESTED SOLUTIONS
 

  • Drain system and lower temperature.
  • Check with the hot melt supplier.
  • Select a different hot melt.
s

Charring

 

PROBABLE CAUSE

  • The temperature is too high.
  • Hot melt charring on the side walls.
  • Air oxidizing hot melt.
  • Poor stability of hot melt.

SUGGESTED SOLUTIONS
 

  • Lower the temperature in the tank.
  • Keep the tank full.
  • Close the lid, and consider a nitrogen blanket.
  • Decrease the temperature.
s

Pop Opens


Adhesive on 1 substrate

PROBABLE CAUSE

  • Insufficient glue amount.
  • The temperature is too low.

 

SUGGESTED SOLUTIONS

  • Increase the pressure or nozzle size.
  • Increase the temperature.

 

Adhesive on 2 substrates

PROBABLE CAUSE

  • Too much adhesive.
  • Poor compression.
  • Shifting during compression.
  • The temperature is too high.

 

SUGGESTED SOLUTIONS

  • Decrease glue application.
  • Increase the compression time.
  • Correct the compression.
  • Decrease the temperature.
s

Stringing / Drooling

PROBABLE CAUSE

  • The temperature is too low.
  • The pressure is too low.
  • The nozzle is too far from the substrate.
  • Poor shut-off of the nozzle.

SUGGESTED SOLUTIONS
 

  • Increase pot temperature.
  • Increase pressure.
  • Adjust nozzle.
  • Repair or replace the spool valve.
s

Smoking

PROBABLE CAUSE

  • The temperature is too high.
  • Poor stability of hot melt.

SUGGESTED SOLUTIONS
 

  • Lower the temperature.
  • Select a different hot melt.
s

Uneven Flow From Nozzles

 
PROBABLE CAUSE

  • A nozzle is clogged.
  • Remote nozzles in multiple nozzle set-up may be affected by pressure drop.

 
SUGGESTED SOLUTIONS
 

  • Clean or repair the nozzle and check the filters.
  • Increase the temperature or pressure slightly.
  • Install larger nozzle orifices on the remote nozzle.

Other Resources

Calculation Tools:

Adhesive Calculation Guide (PDF)

Trouble Shooting Guides:

Liquid Adhesives (PDF)
Hot Melt Adhesives (PDF)
Laminating Adhesives (PDF)

Need additional help?

 

Call Technical Support At: 317-210-7170