He280 hotend nozzle

[chuyuanver]

Recently I ordered a .4 mm brass nozzle from seemecnc official website and ever since switching to that nozzle I've had a lot of problems printing. Now I changed it back to the original .5 mm one, it prints much better. When I am changing back the nozzle, I noticed one thing. The two nozzles are of different design (photos attached below) and the nozzle tip from the heat cartridge differs by about 1.5 mm ( old one 4.5 mm and new one 6 mm). I see in the instructions that the nozzles are needed to be screwed close to the heat cartridge, quote from instruction "Be sure the Nozzle is screwed in almost all the way before starting to tighten. You should be able to see one row of threads when fully tightened." So I am now worried that this 1.5 mm difference in the nozzle can actually cause some problems. I am just guessing though, and wish to discuss a little about this here.

[unnerv]

I noticed the same thing, as I had a clog in my original and installed a replacement that has the new shape. Both of mine are .5mm I left the same amount of thread exposed, which meant that the longer nozzle required a recalibration. Since I was doing that, I also PID tuned thinking since the newer one has more mass that might affect temps. The new nozzle seems to print fine, although I have found that it picks up a lot more melted plastic on the tip. I have to clean it every time I print or there are globs that work their way up the sides of the nozzle. The old nozzle hardly ever had any plastic stick to it, and only needed to be cleaned once in the last 6 months. Other than that, no problems in the last 10 or so hours of printing with the new nozzle.

Maybe redoing the simple calibration, the advance calibration and PID tuning saved me from what you are experiencing?

The next time I go to change nozzles, I may try an e3d v6 since the shape is more similar to the old one and hopefully it will stay cleaner

[Doug68]

I recently did similar with a 0.7mm up from a 0.5mm (both stainless) the stick out is clearly more with the 0.7mm.
I didn't know there was an instruction to limit the number of visible threads but that makes sense.
On mine I ran into issues with the new nozzle, looking at the print and measuring the tempt of the nozzle I guessed this was due to not being hot enough. I've bumped up the temp to 230c for PLA which should be too hot I think but the highest temp I can record from the nozzle is 200c even at this setting.
Maybe try 10c or 20c hotter and see how that runs?