Stringing after hot end replacement.  

RE: Stringing after hot end replacement.

what exactly did you change in your Full Hotend Replacement?
Assuming you got the correct parts,  the performance should be similar to before... 
If however you got the wrong heater, the temperature fluctuations could be massive. as this is the Mk3/Mk3S forum,  you should be using a 24 volt 40watt heater.  (If you accidentally got a 12 volt heater, it would try and draw 4 times the power, and if it didn't blow the fuse, you would experience exceptionally fast heating and massive temperature spikes. )

can you attach photo's of your heatblock, please, showing the ends of the heater and thermistor? (just to check installation,)

Chances are you need to do a PID tune, and possibly new temperature towers if you changed the thermistor and heater. 

regards Joan

RE: Stringing after hot end replacement.

@joantabb

Hi 

I am currently at work and don't have a picture of the assembled hot-end but I did follow E3D's assembly video to the T.  When ordering the parts from Prusa I  follow the links to all the individual parts on the fully assembled E3D V6 hot-end on the store page for all parts but the heat break and hardened steel nozzle. I ordered the Mrk2's heat brake because that what it says to change out in  the video. That also happens to be the stock heat break for a E3D V6 hot. The one that comes with the Pruse Mkr3/s  is mod-ed for Prusa. If you watch the video you'll see how. I read some articles to make sure and that dose seem to be the case. I have provided a screen grab of my recent order for you, to see what I got for the swap from Prusa. I will update this post when I get home with a photo of the assembled hot-end.

Thanks for the help! The community is one reason i got into 3D printing.

G

RE: Stringing after hot end replacement.

Hi Atlas, My mk2 has the modified heat break, it was only the  early mk2's that had the e3d  standard heatbreak

regards Joan

RE: Stringing after hot end replacement.

@joantabb

Hi Joan, 

Here are some more photos for you. Also those articles I read must have been wrong then. They were saying that it was the mark2.5 and after that came with the modified heatbreak. Do you think it could something to do with the hardened steel nozzle? That is the only other part that I can think of, that was also different form the stock mrk3 hotend that I swapped out.

Thanks again,

G

RE: Stringing after hot end replacement.

@Atlas, Hi G, 
those items on your list look good... 
I am a sad person... I had a bit of a giggle at the PTFE Tube...    the Prusa Knowledge Base shows the Mk2.5, Mk2.5S, Mk3 and Mk3S as having a 2mm ID cold end liner PTFE Tube, and the knowlegde base says that the printers with MMU2 should have a 1.85mm ID PFTE Cold end liner tube, 

and then they supply the same part for all printers on the spares page....

I would suggest that if you have enough slack in the thermister wires you could route them over the top of the heater wires, this would make them a little less likely to be damaged in a blob of doom. 

I note your nozzle has a tiny space above it, which is good, and as long as you hot tightened it, you shouldn't have issues with that. everything is so clean... At the moment...   and that the heater is located properly. 

I expect that you removed the part cooling shroud to make the pictures easier to take. 
don't forget to restore that... 

so, why are you getting stringing...  I don't know...      Did you do a PID Tune?   (available from the LCD Menu)

Did you raise the temperature of the nozzle because of the hardened nozzle? if yes, try again with the normal temperatures

did you check the marking on the nozzle? does it indicate 0.4mm?

Could you retry printing with the Nozzle temperature a little lower?

It might be worth running a temperature tower first,  

best wishes, Joan

RE: Stringing after hot end replacement.

@joantabb

Hi Joan,

Thanks for the suggestions and sorry for the late reply with Thanksgiving Holiday it really pushed me back. To answer all your questions yes i tried all that and I Loved your suggestion about the thermister wires I made that change. But after 6 hours of me trying almost everything I could this of a few days ago, yesterday out of no where it started working fine. And now I'm even more confused then when i started having the problem.

Thx G

RE: Stringing after hot end replacement.

@atlas

Ah well, 

let's hope the good service, continues.

regards Joan

RE: Stringing after hot end replacement.

Now I have exactly the same problem .. how did you fix it?