What methods do you use to clean a nozzle used for PLA without damaging it?
First heat up your extruder and then use a very fine drill (like the dentist use) and clean, this methode is best with clogged extruders. Then use your new filament and extrude as long as needed until you got a solid color. Hope this helps.
Use the wire string from a guitar to clean the orifice, you less you have access to wire gauge drill bits. It’s almost impossible to clean the orifice with a drill bit without enlarging it…
@Joost_Urbach how could I NOT scratch the nozzle with that drill? It’s sharp and much, much harder then the brass.
I have ordered accupucture needles. They are stiffer then guitar string and come with a handle in packs of 100.
Do idea how they perform yet.
What do you do against soft clogs that don’t block the hole permamently?
You need a steady hand I admit that but I understand now that the inside is not your question. The outside of the extruder I use a paper towel and head up the extruder and wipe of any PLA. Sorry for the confusion.
I mean the inside. Lightweight dust that doesn’t start to completely block the nozzle but restricts the flow when it gets compressed.
The kind of dust that makes your filament exit at an angle instead of straight down.
The stuff that doesn’t develop into a problem until you are 8 hours into a print.
Heat up, extrude a bit. Set heat to 65-80° depending on your PLA. Pull out PLA. Typically cleans everything.
I found an other methode from a friend of mine. He says: “retract the filament, unscrew the nozzle, put it in nail remover, give it 12 hours, dry it and your nozzle is ready to print.”
I haven’t tried it but everything helps.
You cannot unscrew the nozzle in an Ultimaker II, It’s a single piece with the heater block.
12 hours to clean is also a terribly long time and what foreign materials would nail remover remove?
Dust is mostly made up of dead human skin, hairs and fibers of clothing and plants.
@Joost_Urbach That will work with ABS (assuming the solution has a high concentration of acetone), but not PLA.
For PLA you can use MEK and heavy personal safety eqipment but it’s usually not the PLA you want to remove.
It’s everything in the nozzle that is NOT PLA.
The Bukobot method of cold-pull gets recommed a lot.
It’s old but you may get some ideas from my old post: http://www.tridimake.com/2012/10/clean-hotend-and-nozzle.html
I also have an ultimaker ll but besides that I am a metal fabricator and I use oxy acetylene torches all the time the tip is made from copper and there is a tool that I use to clean that when it gets clogged with molten metal. It’s called a tip cleaner and it has lots of little wires that are various thicknesses and are like little files that you poke into the end of the torch. These tip cleaners are very common and can be bought for two or three dollars at any welding supply store. That is what I would use if my printer was clogged. I would heat it up to 260 c the insert the appropriate size tip cleaner (I think I would want to use a vernier caliper to measure and select the right one probably .4 mm or less) or simply buy another one.
I heat up the nozzle with a lighter then quickly hit it with canned air. Opens right up with PLA and ABS.
Cold pull with nylon is the best way I’ve found. I couldn’t believe the stuff I pulled out of a basically new nozzle.
@Joe_Spanier I think this is the best suggestion based on his experience and would be the least risk of potential damage
Don’t use a drill bit! Brass is soft, and just the act of inserting it and wiggling it around in there will scratch your nozzle and make the orifice out of round.
If a blockage came into your hotend the best way of getting it out is to remove it from the direction it came in from.
Bukobots pull method is by far the best, safest and easiest method for doing this and will clear almost any blockage. This is the method we recommend to our customers at E3D.
In the rare event that some piece of debris is completely obstructing the nozzle orifice such that you can’t get nylon deep into the nozzle to grip the debris and extract it you might have to put something up the nozzle orifice to unblock it. This should not be a sharp, hardened piece of tool steel that is designed to cut metal. You want to use a piece of soft wire, copper wire from electronic cabling is ideal here as it is soft enough to not damage the nozzle.
Use the wire to push the blockage away from the orifice while hot, and then go back to the warm pull method to extract the debris.