I’ve change for a CHT 0.2 harden steel nozzle. But i was getting blockage.
So I’ve installed the 0.4 CHT.
Since then, I had first layer NO adherence. Not bad adhesion, No adhesion!
ASA the melted filament comes out, it stick to the nozzle and not the bed then drags it it on the plate. The result is a big blob on nozzle.
The only initial G-code that sticks is the purge/prime lines.
Even then, there’s a blog on initial line.
What I’ve done:
Full calibration (vibration, bed, …)
Cold pull filament.
Cleaned with soap and alcohol plates.
Tried other textures plate.
alcohol cleaned nozzle
Increased first layer bed and/or filament temp and height
Filament is dry (under 10%)
Filament is :Overture rock PLA
I’ve changed for another PLA (Elegoo black PLA).
Seem to be better but still not perfect. Filament is adhering to plate just barely.
So I’ve swapped back to a genuine bambu harden steel nozzle.
Without any calibration of bed or other calibration, I’m back to perfect adhesion.
The nozzle kit is “V2.0!! Up to 500°C, 3D Upgraded Bambu Lab Hot-End Version Hardened Steel Nozzle Assembly Kit, Compatible with X1 and P1P” and I’ve swapped nozzle for CHT.
I’ve inspected the V.2 nozzle and there’s a layer of crust. Is it possible there’s a leak and this affects that much the adhesion on plate?
I’ll try to use pipe glue and see if it seals the leak.
I would suggest a simple test to see if the plate/bed is the problem. Slice a simple and small test cube somewhere near each of the four corners of the machine (without going in to the purge line area). Check the option to print each object separately and make sure to run the bed leveling at the beginning of the print. I’d also, wash the plate with soap and water first to ensure everything is set to succeed. If it prints out fine, there are a few options, but may mean the middle of the plate is used up.
If it continues to fail the nozzle may be an issue.
Lac of adhesion wiht a 3rd party nozzle sounds like the height of it it wrong which means it’s too high off the bed, or the part/aux fan is aimed incorrectly up or down a little.
The fans are fixed and can’t be aimed, so not there.
Small differences in nozzle length can be handled by the auto-levelling - if too great it will probably inform you of a failure to level. But even if that passes, the nozzle may be the wrong height to hit the cleaning pad.
When I first read this quote by you I assumed you would be using a 0.6mm or 0.8mm nozzle, because those are two nozzles that would benefit from a hotend with a higher flow rate. But then I saw from your OP that you went in the opposite direction, to a 0.2mm nozzle, and falling back to 0.4mm when that failed.
So… I’m guessing you’ve tweaked your settings to go much faster than usual with a narrow nozzle. Compared to the trails blazed by others who have reported on their use of the CHT nozzle, maybe (?) you are the first to be attempting this. It would maybe explain why you are getting the leakage: perhaps you are putting the melted filament under more pressure than it’s spec’d when, especially when/if you’re presumably pushing the 0.2mm nozzle almost all the way into the build plate with an extra short layer height.
I will keep this in mind when I goto try the .02mm cht nozzle I just recieved off amazon. I got .02, and .04, and .06. But I got the .02 for different reasons. I just wanted the extra detail and resolutions possible with the smaller nozzle, not necessarily more flow, and if I remember correctly bambu doesnt offer a hardened version of the .02, but the cht nozzles do.
Now the question is, will the cht nozzle .04 actually give more flow than the bambu .4? i’d assume so, due to the fact the cht is pretty much engineered to do so. from what I can see, the bambu vs cht hot end (nozzle and heatsink, no fan) seem to both be around the same size, though I don’t have calipers on me to measure for sure, I would think the bed leveling process would take care of any small discrepancy. I actually followed a link from someone who had bought the exact nozzle they reccomended me to get and was known working, but I have yet to actually install it.
A.
You said that you’re printing PLA, so… why do you need a 0.2mm nozzle that’s made from hardened steel? Wouldn’t the bambulab 0.2mm stainless nozzle meet your need?
That way, by sticking with a stock configuration, it should “just work” and your struggle will be over.
Cost savings was one reason, the hardened nozzles would, I assume, last longer than stainless regardless of what I was printing, but i hadn’t mentioned what filament I was using. I have pla-cf ordered and on the way, so that was reason number 2. The third being cost savings again, because I can get 3 replacement screw in nozzles of the hardened non cht variety (now that I’ve bought the hot end that’s threaded) for $6.99
3 nozzles of the hardened cht variety for $10.99
3 nozzles or more for every one bambu lab hotend seems like an okay price , if and only if, it works. There is at least some evidence others have got it to work, both here and on Youtube, so hopefully I can figure it out as well.
My main reason for 0.2 was to have better quality but man took longer.
Another reason was for a better waterproofing.
So I though going with CHT and maybe compensate partly.
And because of blockage, went to 0.4.
what heatpad are you using? The one that comes from aliexpress or amazon on v2.0 with cht nozzles is bad. does not have enough power. I had a same issues, switched just the heatpad and termistor to original bambu one and 300 hours of printing later cht 0.4mm is still kicking ass.