Ciao a tutti, un anno fa ho ricevuto l'hotend che potete trovare descritto a questo indirizzo (mentre questo è il sito principale http://regpye.com.au/ e questo il suo shop online) per svolgere dei test su proposta del designer/produttore. Dopo aver svolto i primi test, ho trovato l'hotend così affidabile che ho deciso di utilizzarlo sempre per la mia stampante. Da allora ho svolto numerosi tesby cristian - Mercato
II had to design an extruder from scratch for my printer to solve that problem. I shared the design here, maybe you can find some cue to fix your extruder too.by cristian - Printing
QuoteLoboCNC Quotedc42 What formula do you think extruder hysteresis compensation needs to follow? My fork of the Duet firmware allows for a term proportional to extrusion rate to be added to the extrusion amount, but it isn't successful at avoiding over extrusion at corners. I am prepared to try other ways of modifying extrusion, but I would like a mathematical basis to work from. I'm ecstaticby cristian - General
I am very sorry for the delay, I wanted to do some final improvements to the model (not to its readability, though!) before releasing it, and the last days were busy... Anyway, the openscad model is finally attached. While you are of course free to modify it the way you prefer, the current model is thought to be used in a precise way. The PTFE liner that is used to guide the filament through theby cristian - Smart_Rap
Quotelyscanthrope I really like the design of this extruder! Would you share the files? Sure. If you plan to use it I must also write you some tips. If you want the STL no problem, if you want openscad source, beware it is a total mess. I will share the files asap. Quotelyscanthrope I was wondering if the bearing is mandatory can't you just push the filament against the ptfe? (with a supportby cristian - Smart_Rap
It looks like all the motors were skipping steps, not only the extruder one: the edges of the object become shorter and shorter. Maybe your power supply is not powerful enough, or your board.by cristian - Printing
Have you tried again with a taller print?by cristian - Printing
Ooze is quite normal at the end of the print (at least for me), and the only problem you may have when you tighten the nozzle too much, is that you break something. If you did not already, then it is fine.by cristian - Printing
Quotegeemoto That was probably poor wording, it has about 2.5cm zone of fins, but I'm not sure what the transition zone size is. If I were to approximate, the distance from the ceramic heater to the first fin is <1cm. The temperature feels ~45C at this point (by touch), so the temp drop is ~150C over 1 cm. This sounds OK. Then I really run out of ideas, probably a geared extruder is the way tby cristian - General
Quotegeemoto I 'think' the hexagon is supposed to be a pretty good hotend, it does have a fair length transition zone, maybe about 2.5cm. 2.5cm is long, I would not be surprised if you had problem with that hotend then. In my hotend more than 90% of the temperature transition happens in less than 1.5cm. Quotegeemoto If the hexagon hotend isn't good enough, I don't know which hotend would be!by cristian - General
Quotegeemoto Given the extruder doesn't skip or slip, is it still possible for uneven extrusion? E.g. if the hotend gets 'jammed', and the extruder still has enough force to push, could the filament compress in the hotend, and then release the pressure all at once when the 'jam' is cleared? If that could happen, then simply getting a more powerful or geared extruder may not solve the problem. Ifby cristian - General
Another thing to exclude: is the filament unrolling smoothly from the spool? Yet one more: are you sure you are not overextruding? Although we may rule this out anyway because with spiral vases even if you overextrude a little it is not a problem.by cristian - General
Quotegeemoto I'm wondering if it's something to do with friction in the hotend...maybe exacerbated by filament swelling due to water absorption (I've had this filament for about 8 months now). Even if friction is increased by water, you should be able to print properly. Otherwise it means that your extruder is working at its limit, at least with that type of filament. Maybe you have been unluckyby cristian - General
My PID parameters would not work for you because my heater block is not standard size: the hotend I have is not very known, and this is unfortunate because this hotend is virtually impossible to jam (I have been trying for almost a year now, and I never managed). If you cannot solve your problem otherwise, you may want to have a look at it. Meanwhile, I think you have to play with cooling, isolaby cristian - General
Quotegeemoto I realized that I actually have the extruder output data as well, so we'd be able to see if the extruder was simply outputting more power to compensate for the temperature swings, it doesn't seem to be the case - at least not to a huge degree Too noisy to tell... BTW, what nozzle diameter are you using?by cristian - General
Quotegeemoto Hmm, that's interesting. I could take the bed thermistor and kapton tape it to the hotend, it probably won't read the same temperature - but at least it should remain stable. I overlooked this sentence. First, if you chose the bed thermistor beware that you may trigger a MAXTEMP for the bed, depending on your firmware settings. In that case, either you increase MAXTEMP in the firmwby cristian - General
Quotegeemoto but the nozzle fan may be turning on and off. May you produce the same graph with the nozzle fan also constantly on (or off)? It is not optimal for printing quality, but it may remove some noise from the graph.by cristian - General
If the fan is blowing constantly and you correctly tuned PID parameters, the graph looks suspicious to me. There is something wrong with either temperature or its detection in my opinion. Or your thermistor is very, very imprecise but accurate (unlikely). I had an issue with wrong temperature detection once, and in the end I had to re-wire the thermistor: temperature reads were drifting by 20-30by cristian - General
Looks like jamming, so it may be any of the problems previously mentioned. You already excluded some of them, the next to try is for sure temperature. To do that, I usually connect another thermistor to the board and I make it slide inside the hotend in the place of the filament. Then I make a dry print to see if the two thermistors give consistent reads during the whole print. It is not a 100%by cristian - General
If you clearly noticed that the filament stopped flowing from time to time, then it is not backlash. Moreover, backlash is not "cumulative" in the sense that if at some point you have some apparently missing extrusion, at some other point you must have an excess of extrusion that compensates for that, and according to your description this is not the case.by cristian - General
If you try to pull and release the wires of the thermistor repeatedly during the print (without damaging them of course), does the temperature read change abruptly?by cristian - General
I'm in the first ten too!by cristian - For Sale
QuoteImpressMeZosk Dans Pronterface on peut très bien régler la temp à la volée pendant l'impression mais avant il faut mettre O (zéro) comme valeur dans Slic3r au moment de la configuration du fichier. J'ai essayé, on peut le faire aussi si dans slic3r il n'y a pas zero comme température donc Pronterface fonctionne aussi bien que Repetier. Dommage seulement pour le script GCODE qu'on peut pasby cristian - RepRap Groupe d'Utilisateurs Francophone
It is more likely that the filament bends in some place where it is not constrained enough. I had this problem too and I re-designed my extruder so that the filament is never free, from the hobbed bolt to the nozzle.by cristian - General
C'était la censure !by cristian - RepRap Groupe d'Utilisateurs Francophone
QuoteOne-T Peut importe ponterface ou repetier sont des logiciels de fabrication. Cest slic3r par exemple dans les 2 cas qui dicte la tempé Avec repetier on peut la changer en temps réel pendant l'impression. Je ne connais pas d'option dans slic3r qui permets de changer la température sauf pour la première couche.by cristian - RepRap Groupe d'Utilisateurs Francophone
Quotegaryhlucas Note that deflection in the frame will produce a position error that will be huge for small parts and probably much less for very large parts. I would relate this argument more to layer height and width than to the global size of the part to be printed, in particular if it has sharp corners. Of course layer height and width may in turn be considered proportional to the size of tby cristian - General
Quoteo_lampe As a customer I wouldn´t accept a big print where the errors are also" scaled up". I´d expect the same sharp corners and flat surfaces as with a common 0.4mm nozzle. -Olaf It is impossible to obtain the same sharpness on Z with different nozzle diameters. A 1mm nozzle will always give you rounded corners with a radius of at least 0.5mm.by cristian - General
What is your thermistor type? MINTEMP and MAXTEMP may be triggered by open circuit (for example wires not touching well) or short circuit. And you should always have spares of everything that can be broken (i.e. of almost any component). Please don't give up! I have thought and said it so many times, but when you finally make it work it is a huge satisfaction.by cristian - General