Ultimaker UM2 Assembly Manual page 50

4. Lubricate the left hole (the
orientation) with copper gre-
ase. This is to prevent corro-
sion between aluminum and
stainless steel
5. Attach the Teflon insulator
coupler, the hot-end insulator and
spring together. Place it on the
hole which you just lubricated the
copper grease.
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