Whenever I remove filament I’m noticing this “blob” where I don’t recall seeing it before. Is this an indication of a clog in my nozzle or tube or perhaps heat creep?
It’s a CR-10 and I’ve recently started getting clogged nozzle and filament breaks.
I suspect the blob is approximately the same diameter as the body of the filament: I think what you’re seeing is the end of the filament stick to the inside of the hotend, and as you pull, it stretches and shrinks behind that section, until that section finally pops loose and comes out. (The next step of this is simply breaking off the filament and leaving the end adhered in the hot end, which I’ve done.)
I prefer to cut the end of the filament and push the new one through. What this is is the plug, the semi molten portion that forms a seal to push the molten material through.
I’ve found that when you remove it hot, some material can stick to the cold area inside your hotend. This creates additional friction and can lead to jams. So it’s better to just cut the filament and push new one behind it.
Another thing I do is have a filament wiper. This wipes any lint off before it goes in the hotend. I put a drop or two of oil on it, which puts a very fine film of oil on the filament. This keeps it from molten material sticking to your cold end on retract.
I agree with both of the posts above.
I had that. Discovered after experimenting it had to do with over retraction
@Stephanie_A Carefully with the oil, as it may be a layer separation. I saw a test on youtube where this was tested and the oily prints weaker.
if you actually remove filament by force this is how it looks, you sohuld slowly unload the printer head within settings of the machine. to nocie blocked nozzle is to observe while loading filament is it is falling straight down from hot nozzle. if you observe bubbles or steam means filament is not stored properly or you set temp too high. if it would kink to one side or stop flowing that might mean clogged nozzle, or burnt out teflon tubing inside nozzle that need replacing. definitly no oil is allowed nowhere near any kind of plastic, it will contaminate the print. remove oils with isopropynol alkohol, best to mix it withsome water to remove any alkalines too.
to clean the nozzle usually use small drill bit, otherwise unscrew it and bake it on top of a flame to cook plastics out, and then clean by inserting piece of filament and quickly pulling it out. do not scratch inside of the nozzle with nedle etc that will cause problems in the future.
@Piotr_Sitko in other words what are you seeing is normal, what you need to pay attention to is the very end of that blob - if it does not have any black spots or discoloration cause by contaminants like iol from your hands, dust, random debries.
I always use change filament option in menu and having no problem.