florianlb

Bonjour peroxyde, Bienvenue dans la communauté Ultimaker. J'ai acheté un Ultimaker il y a deux mois pour des raisons qui sont similaires aux tiennes : j'aime bien concevoir des objets, et c'est donc un vrai régal de les voir imprimés. En ce qui concerne tes questions, je ne peux répondre que partiellement. Oui, les couches déposées par l'Ultimaker sont bien de 0,1 mm. Les moteurs pas à pas utilisés te permettent d'ailleurs de descendre en-dessous de cette valeur. Idem pour la précision dans les déplacements, qui est bluffante. Après, cela devient plutôt une question de temps d'impression. Dans le logiciel Cura (option de référence pour l'Ultimaker), le profil de qualité "fine" correspond à des couches de 0,1 mm. Pour tirer le maximum de l'imprimante, je seconde l'avis d'yzorg : il te faut bien connaître la géométrie de ton fil à extruder et sa température de fusion optimale. Cela signifie que tu vas quand même passer un certain temps à étalonner ta machine avant de sortir des impressions "optimisées". Pour les pièces imprimées de grande taille, il est effectivement possible de constater de la déformation. Cela dit, tu peux toujours jouer sur la température d'extrusion pour contourner ce problème. Le lit chauffant est nécessaire lorsque tu imprimes avec de l'ABS, alors que l'Ultimaker est faite pour du PLA. Tu n'en as pas besoin à priori. Pour tes questions sur le fil : étant donné qu'il est guidé via un tube Bowden (diamètre intérieur 4 ou 5 mm), c'est ça qui va limiter les géométries de fil utilisables. De plus, tu renseignes dans le logiciel d'extrusion (Cura) le diamètre effectif que tu utilises pour calculer le nombre de tours par seconde de ton extrudeur, donc ce n'est pas un point particulièrement critique. D'après ce que j'ai vu, tout le monde utilise à peu près le même type de fil d'environ 3 mm de diamètre, mais avec des couleurs différentes, en PLA. Une dernière précision : le prix de l'Ultimaker est un peu plus élevé que le montant de ton budget... J'espère que cela répond un peu à tes questions. Florian

Okay, will try this. In fact, I'm not sure it's a Bertho upgrade. This is the standard extruder drive that came with my Ultimaker.

Hi guys, it seems my Ultimaker is now on the way to becoming normal. After printing the horseshoe I was discussing in my last post, my printer still grinded the filament. Somehow, I decided to print another horseshoe and fit that one on the extruder bowden end. Magically, my filament stopped grinding and I've been able to successfully print a number of small objects. For example, I printed snowygrouch's fan duct for cooling the printer head. However, things are not yet properly solved: my last print attempt ended because the filament started getting too thin and brittle. Could anyone have a look? Also, my printer head is leaking. Thanks for everything so far. I've learnt a great deal with this. Hope to solve the remaining issues too. Florian

@snowygrouch: Indeed, I'm missing that part. However, I was able to print out a replica I made this afternoon after cleaning the nozzle. See attached picture, left. It's 1.5 mm tall. Is that enough? Could anyone provide original horseshoe measurements? After printing out that part I though "great, this problem is solved" and went on to print out your cooler design for the hot-end. That didn't go so well: I ended up with the usual problem: the extruder driver grinding the filament and my print unfinished (see picture, right). @daid: I took a full picture of the extruder head. Do you see anything unusual? So I still have my last resort option: use my spare hot-end. What do you think? Hope to hear from you guys!

Hi guys, while reassembling my hot-end, I realized my ultimaker was missing its horseshoe (see attached photo). Might this be the reason why I can't print correctly? Thanks in advance. Florian

Here's some more information. I just tried pushing the filament in by hand. I observe a plug forming in the PEEK part. When I pull it out, there's some secondary plug coming after. After pulling out that part of filament, I pushed my screwdriver through the hot-end. It turns out that the plastic comes flowing out on the nozzle. So maybe this is okay like this after all. I'm attaching a picture of the plugs. Next step: putting the hot-end back together and retrying printing.

Some more input for you guys: I cleaned the hot-end thoroughly and tried checking for a clog by shoving a needle through the nozzle. Unfortunately, I couldn't see the needle tip from either side. However, judging by the way the nozzle looks both from the inside and outside, I would say it's clean and that I couldn't detect any obstacle to PLA flow. Next step: heating up again and slowly pushing the filament in through the PEEK to check if there's still as much friction as I detected last time.

Hi guys, thanks for the suggestions. First of all, please find attached a picture of my hot-end. Please correct me if it's not mounted the way it should. It's a V2.

Hi guys, so, before swapping nozzles or changing the hot-end, I tried extruding again tonight. After thoroughly cleaning PEEK, brass part and nozzle, I pushed some filament in. After a few mm, I noticed that out of the peek came backflow! I'm very surprised by this. Temperature setting was 220°C. I thought nothing the like could occur at this temperature. I've decided to give extruding another try tomorrow. This time, at a lower temperature to check again for backflow issues. I'll report back here with the results. I'll report back tomorrow on how this goes.

Hey snowygrouch, Thanks for the reply. In fact, I cannot print anything. Tonight, I cleaned the PEEK and the brass part connecting to the nozzle and tried pushing some filament through. It felt like it's the nozzle itself that's clogged. Does anyone know how likely that is? I managed to push a little filament through but then the pressure needed to push further increased suddenly. I really hope to get some input from you guys. The only option I see at the moment is to use my spare V2 hot end and replace my current nozzle with it.

Hi everyone, Sorry to start a new topic about this, but I just couldn't find the help I needed in all the things I read. My history is the following: I've ordered an Ultimaker at the end of October and assembled it. I got my first prints shortly after, but then ran into trouble. The symptoms I got were: the filament stops moving inside the Bowden tube and gets grated by the knurling on the hobbed bolt from the extruder drive. My first reaction was to disassemble the extruder drive (V2) and check the tightening of the spring in the clamp. Long story short: the extruder drive was working correctly. So I figured that the problem lies with the hot end (also V2), after the filament exits the Bowden tube. What I did about the extruder head: I cleaned it entirely at 220 °C and made sure there's no PLA inside (I'm still printing on the stock Ultimaker PLA). I then re-assembled the extruder head and moved the filament until it enters the hot end, by hand. What I realized is that the pressure seems normal while the filament has not reached the hot end and suddenly increases when the filament enters the extruder head. I confirmed that this is indeed the problem by cleaning and inserting filament several times. My best guess is therefore: plugging occurs in my hot end. And I don't know how to solve this. Could anyone please suggest a workaround? Please find a picture attached that shows the sort of PLA plug I pull up whenever I try to clean the hot end. Thanks in advance, Ultimaker Community! Florian