
Stratasys J750/J735/J720 User Guide
4 Operating and Maintaining the Printer
DOC-08040 Rev. R
4-63
To replace print heads, you need these tools and materials:
❒
replacement print head(s)
❒
90% isopropanol (IPA—isopropyl alcohol) or ethanol (ethyl alcohol)
❒
disposable cleaning gloves (supplied with the print head; or use any clean,
powder-free protective gloves)
❒
a supplied cleaning cloth or equivalent
❒
a mirror
❒
a 4-mm hex (Allen) key
❒
a small Phillips screwdriver
❒
the Missing Nozzles ruler
❒
the scale supplied for use in the Head Optimization wizard (Weight Test)
Important:
Before beginning this procedure, ensure that the scale is
calibrated and at least partially charged.
If you are replacing print heads now, the wizard guides you through the
procedure when you click
Next
. Continue with "Replacing Print Heads" below.
Replacing Print Heads
The condition of the print heads directly affects the quality of printed models. You
may need to replace a print head if one or more of the following symptoms
occurs:
• The Head Optimization wizard determines that a print head is defective. (See
"Optimizing (Calibrating) Print Heads" on page 4-56.)
• There are noticeable grooves in the surface of printed models.
• Visual inspection of the head reveals that its surface is damaged—peeling or
bubbles in the nozzle area.
• The printer interface displays a warning or malfunction message relating to a
print head—
❒
Head Heater temperature timeout
❒
Head Heater thermistor open
❒
Head Heater thermistor short
Replace print heads only after consulting with an authorized Stratasys service
provider.
The Head Optimization wizard guides you through the procedure of replacing a
print head, and configures printer components to enable you to perform it. Only
replace a print head with the aid of the wizard.