This solution article will describe how both inner printhead tubes can be replaced on a Leapfrog Bolt PRO 


Tools: 

The needed tools for this maintenance are an Allen wrench size 2 and 3. 



Leapfrog step 1: The preparation

  • In case there is filament loaded into the printhead, please unload it.
  • Turn off the 3D printer and switch of the power. 
  • Make sure that the hot-end of the printhead is at room temperature.



Leapfrog step 2: Get out the upper gland

  • To remove the upper gland unscrew the (upper) set screw on the picture below with Allen wrench size 2.
  • Now the upper can gland can be taken out.



Leapfrog step 3: Put in the new upper gland

  • Be aware of putting a nylon gland in the drive unit in the right orientation (see the picture below)
  • After placing the gland tighten the set screw again. 
  • be sure that there is no pressure applied by the upper nylon gland on the extruder drive gear. You should be able to rotate it by hand.



Leapfrog step 4: Disconnect connectors from the head PCB

  • Disconnect the three connectors (which are indicated on the picture below) from the head PCB.



Leapfrog step 5: Removing the hot-end

  • Disconnect the connector of the hot-end.
  • Loosen the hot-end by using Allen wrench size 3.
  • Remove the hot end.



Leapfrog step 6: Remove the drive heatsink from the drive unit

  • Remove the 2 screws on the bottom of the drive heatsink.
  • And one screw on the back of the drive heatsink. 

 



Leapfrog step 7: Replace the lower gland 

  • After removing the drive heatsink, unscrew the (lower) set screw shown on the picture below. 
  • The gland is now loosend and can be taken out.
  • Ensure that the new gland is equipped with a PTFE tube, as seen on the picture below.
  • A new gland can be placed. Be aware of putting a nylon gland in the drive unit in the right orientation (see the picture below).



Leapfrog step 8: Put everything back in place again

  • Put everything back in place again. Do this by performing step 4 to 6 backwards. 
  • For step 4: Make sure that the connector of the radial fan is placed on the lowest pin of the head PCB. 
  • When everything is assembled, be sure that there is no pressure applied by the lower nylon gland on the extruder drive gear. You should be able to rotate it by hand.