Alternative to acupuncture needles for nozzle cleaning
I don't think I've heard this mentioned before, but I have come up with this alternative for clearing clogged nozzles. The tool of choice in the past has been acupuncture needles, which have their issues. I don't know the range of diameters in which they can be obtained, but the one I got with a Prusa order had a constant diameter of 0.3mm and a length of 30mm. Being smooth, they are not very effective at actually removing material that makes up the clog since they do not "fill" up the 0.4mm bore. Plus being MUCH longer that is really necessary, they are kind or hard to handle and inserted into the nozzle. (You can cut them shorter, but it's hard to do without having a "crook" at the end.)
During a recent visit to my dentist (who also happens to use intra-oral 3D scanners (expensive!) and printers, both filament and resin, for dental appliances and hobby uses as well, it occurred to me that the files he uses during root canal procedures might work for nozzle cleaning purposes. They are actually finely tapered, round rasps and are available in a wide range of diameters and lengths. He gave me a broken box (5 instead of 6 pieces) of size "08", which equates to a tip diameter of 0.08mm, widening to 0.4mm at its widest point. They are available from size 6 (0.o6mm - 0.30mm taper) to at least size 140 (1.4mm - 1.72mm taper.) The size 08 is perfect for 0.4mm nozzles, and the rasping action efficiently removes clogged material from inside the bore. (Do I need to say, "Heat the nozzle before using!"? I cut off the narrowest 1/3rd of the length (at the 0.2mm point) making it easier to handle and less prone to possible breakage of you use too much sideways force. The stainless steel material snapped cleanly leaving an easily insertable tip.
Now you have no reason to fear that next root canal procedure, just ask the dentist for the used files!
You made my teeth hurt this morning just looking at those. 😳
Had to get a root canal a fair few years ago, was on a Friday afternoon and the dentist missed one of the nerves, that was really good fun once the injection wore off, no amount of bourbon took that pain away.
Ended up in a dental hospital getting the offending nerve dragged out, can remeber the relief when the injection went in, and when Murray won Wimbledon.
Great idea, but think ill stick to the acupuncture needles if you dont mind 😁
Hmm. Good find, but I found using any sort of needle, bit, or probe to be overly complex when clearing clogs. I managed to break a needle off while dealing with my 1st clogs back in early 2018, so searched around for other solutions. Fortunately, I read up cold pulls early on and have found that method to be far more effective for actually removing clogs from the hotend rather than just moving them about. I also realized that my 1st (brass) nozzle had been damaged by poking about with the needles and bits, resulting in annoying fine stringing. I replaced it and have only used cold pulls for the last 3 years. It's cheap and can be done with items readily at hand.
I wouldn't use that kit on my nozzles...
In about 6 years I dont recall probing my nozzles!
If I get a blockage, I normally raise the nozzle temperature and try to push the filament into the extruder, if that doesn't work, I take the nozzle out and try again... that usually works. if I have to take the nozzle out to clear a blockage, I generally use the opportunity to fit a new nozzle (I keep spare Brass and steel nozzles in various sizes)
I take the point of view that if there is some crud in the extruder, blocking the nozzle that will not melt and push through, moving it with a pokey stick, is unlikely to give a long term solution. and if the crud is moved by the pokey stick, and doesn't come out of the nozzle, then it's still lingering inside the extruder waiting to bite ya backside next time you're not watching. being a cheapskate, I don't use expensive nozzles (I don't usually use exotic filaments)...
I have heard of people damaging ruby nozzles and hardened steel nozzles with pokey sticks... if you chip your ruby, the nozzle is scrap, same with hardened steel, chip the nozzle orifice or meplat, and the nozzle is Junk... brass is a bit more forgiving, but not guaranteed pokeystick proof! Lol...
Only for brass nozzles
If I have a clogged nozzle and I can't remove it on the printer, I disassemble it and heat it with the blowtorch (gas burner?). Right temperature is reached, when material is burning. Then let it cool down, afterwards use an acupuncture needle to clean the residues of the burnt material. I make this from time to time without any print quality issues. Nevertheless it makes sense to have spare nozzles. Don't use this procedure on hardened steel nozzles and nozzles with special coatings or ruby nozzles.
Best regards, Clemens
[...] If I have a clogged nozzle and I can't remove it on the printer, I disassemble it and heat it with the blowtorch (gas burner?). Right temperature is reached, when material is burning. Then let it cool down, afterwards use an acupuncture needle to clean the residues of the burnt material.
Before tossing a nozzle, I'll hold it in front of a hot air gun, then insert some cleaning filament and let it cool, then do a quick nozzle-only "cold pull". It takes careful timing to avoid melting the filament completely, but it sometimes pulls out some nasty stuff that I couldn't get out with a regular cold pull.
There was a thread here recently that mentioned dunking nozzles into ... acetone or paint stripper ... not sure which. Someday I want to experiment with that. Those nozzles that use tiny number etchings get dirty quickly and are hard to read. It would be nice to get them shiny again.
I only presented this as an alternative to acupuncture needles. If you never have a nozzle clog bad enough to need removal-by-probe, great, don't use it. But, for the reasons stated, these files do a better job (for me) than the acupuncture needles. Your mileage may vary, of course.