MakerBot/clogged printhead

Clogged Printhead

• 
  was not glogged completely all the way through .. PLA broke off in the middel of it
• 
  PLA was soaked in acetone .. which is good for ABS plastic but not PLA
• 
  good not see the nozzle clog from this angle

Soaked in Meythlene Chloride

Soaked in methylene chloride overnight and it looked really clean:

• 
  could see light through nozzle
• 
  feed tube was clean also

Put Back Together

Had problems putting together because the ceramic, Kapton tape and Kaowool Cerablanket ceramic insulation was lost. Had some Kapton tape and used steel wool in stead of the Kaowool, but did not seem to have an effect.

• 
  Fan guard and heat sink
• 
  screws
• 
  temperature sensor stayed with the wiring harness
• 
  heater
• 
  stepper motor
• 
  screws and standoff

Still Had Problems

• PLA curling back into the nozzle
• Stepper motor making clicking sounds
• PLA sputtering and coming out lumpy

Tried:

• Printing at a slower speed solved some of these problems but every print out was successively worse.

Called MakerBot

Yes Makerbot has a phone number! 347-334-6801 Had earlier created a support ticket.

Asked to extrude a large amount .. told them it came out lumping and curled towards the nozzle. They promised to send a $120 nozzle, feed through, heater, temperature sensor assembly since it was under warranty. The nozzles are $20 each if purchased separately.

Butane Torch

Removed the wire following the unload instructions of the Makerbot. Could see PLA coating the inside of the nozzle. Put the nozzle in the blue flame of a butane torch and after a minute it all came out at once in a blob. At this point tried to clean the inside of the nozzle by scraping an Allen wrench inside of it, and ran a wire through the 0.4mm hole back and forth like a pipe cleaner.

Nozzle still did not look symmetrical (like the PLA was still going to curl back into the nozzle. So brushed the end of the nozzle shiny clean with emery cloth until the hole looked symmetrical. Worried that may have enlarged the hole.

Ordered 0.4mm and 1.75mm drill bits so can begin flitering with making our own print nozzles.

Did not try to burn off the PLA, but it looks like it doesn't burn that well. Some dripped onto the butane flame guide and did not burn off or even change color. When scrapped off, it appeared to clean the butane flame guide.

Put Back Together

MakerBot cleaned nozzle with Kapton tape and Kaowool insulation

Obtained the Kapton tape from Makerbot and the Kaowool insulation from a hardware store that sold wood stoves.

Other ideas brainstormed to solve the problem:

1. Soak again ... stronger ... longer, different solution
2. Purchase new nozzles at $20 each
3. Design a new nozzle

Still Not Printing

Close up of nut and bolt print failure

failure to print example nut and bolt, bracelet and a square block

Have tried numerous times to level the build plate, extrude lots of stuff, heat up the print head to clean it. Have replace the Kapton tape 3 times. Taken the print head completely apart and put together 4 times. Very frustrated.