Show all posts by user
Everybody here is a developer. Share what you are doing !
Re: Layer Adhesion Problems with ABS-PC and Polycarbonate - 10 years ago
I was also thinking that bond strength is affected by how thoroughly the interface is molten. So I decreased the feed rate to 10mm/sec and layer height to 0.1mm in order to really melt everything together with the nozzle at 250°C alone. Didn't work. In fact, I couldn't notice much difference from my other test settings.by uGen - General
Re: Layer Adhesion Problems with ABS-PC and Polycarbonate - 10 years ago
I have tried 0.3, 0.2 and 0.1mm layer heights with a 0.4mm nozzle. Good that you mention this - AFAIK, Taulman recommends printing the 645 nylon with layer height == nozzle width, so maybe other plastics behave similarly.by uGen - General
Re: Layer Adhesion Problems with ABS-PC and Polycarbonate - 10 years ago
From how I understand the issue, layer adhesion should be affected mainly by the temperature of the nozzle as it welds together the previous with the current layer...the heated chamber is more of an aid against the object deforming. But thank you for your insight, in case I get stuff to work, I try to bump temperatures up a notch.by uGen - General
Re: Layer Adhesion Problems with ABS-PC and Polycarbonate - 10 years ago
@karlo: ah, what a bummer! Hope that drying the filament in my box with a more potent desiccant helps. @jzatopa: yes, my printer is permanently installed inside a heat insulated box. The inside reaches temperatures around 40-45°C @aduy: I didn't notice any fogging or sputtering like with wet taulman filament. Basically, I took it out of the bag and printed with it right away. Maybe the desiccanby uGen - General
Layer Adhesion Problems with ABS-PC and Polycarbonate - 10 years ago
As new and ever more exciting printing filaments get released, I just had to try out Polycarbonate and ABS-PC for high temperature applications. However, there is one problem: Neither ABS-PC nor pure Polycarbonate exhibits good layer adhesion for some reason in my tests. My setup: -E3D hotend v.4 for 1.75mm filament; thermistor values checked with thermocouple and multimeter to be mostly dead-oby uGen - General
Re: Update on the E3D All Metal Hotend (Now finally shipping!) 
[Lots of pictures] - 10 years ago
Quite surprisingly, the cartridge heater that came with my hot end had to be hammered in (carefully) because the fit was rather tight. Knowing that there had been problems with falsely labeled and oversized heaters, I checked that possibility first, but everything seemed to be within spec except of the fit. Anyway, nice thermal contact, so no worries here @Sanjay: The Kraken hotend looks good!by uGen - General
Re: multiple levels of infill - 10 years ago
Ah, the variable density infill! A group from the MIT Media Lab was working on that, but it seems like either they didn't publish further results or went on to do research on other stuff. However, I am planning to do my bachelor thesis on variable density infill, too, so I have already made some promising tests. Actually, when using skeinforge, slicing the variable density models is way faster thby uGen - General
Re: 2 Extruders, 1 Hotend - 10 years ago
In my experience, the E3D v4.1 hotend for 1.75mm filament keeps only a small plug of molten plastic when you pull the filament out (although the melt zone is supposed to be long). The hotend itself is rather long, though. So to make the filament change more efficient, replacing the long heat sink with a water cooled solution might be an option worth considering.by uGen - General
Re: 2 Extruders, 1 Hotend - 10 years ago
@bobc: yeah, unfortunately...I first attributed everything to language barrier miscommunication as I am not a native speaker either and might have caused misunderstandings in some of my posts myself. @ifala: look, you quoted this: Quoteexcerpt from the starting post of this thread > However, it turns out that someone thought of > exactly the same and got the whole contraption to > workby uGen - General
Re: Dual Extruder mit einem Hotend - 10 years ago
Ich glaube, hier handelt es sich um ein Missverständnis: Was du meinst, scheinen die Feedrates vom Extruder zu sein und was ich meine, Feedrates in einer extra Zeile. Also, z.B. T0 G92 E0 G1 E90.5 F7000 G92 E0 G1 X100 Y200 E10 wäre ja dein Filament einfädeln und eine Bewegung mit F7000 nach dem Wechsel. Wenn du jetzt eine extra Zeile vor die Bewegung packst: T0 G92 E0 G1 E90.5 F7000 G92 E0 G1by uGen - Extruder, Hotends & verschiedene Materialien
Re: Dual Extruder mit einem Hotend - 10 years ago
Ok, das lässt sich nun leider wirklich nicht vermeiden, die Bewegung mit einer anderen als eigentlich berechneten Geschwindigkeit zu fahren. Aber dann wäre es doch besser, lieber ein wenig langsamer als mit zu hoher Geschwindigkeit zu fahren, oder? Führt das mehrfach-Belegen des Extruders nicht zu Konflikten beim Heizen? Also, wenn z.B. Extruder 1 auf 230°C heizen soll, aber Extruder 2 auf 0°C eby uGen - Extruder, Hotends & verschiedene Materialien
Re: 2 Extruders, 1 Hotend - 10 years ago
Sorry, but I don't quite understand what you meant with this part: " well, it was just to clarify that if YOU found an answers to the questions that YOU place yourself ... on MY BLOG You found all the answers to your questions.." I await your further updates with excitement, then...by uGen - General
Re: Dual Extruder mit einem Hotend - 10 years ago
@Hux Flux: die vier 'x' stehen für eine beliebige Zahl, z.B. G1 F2000, um bei der nächsten Bewegung mit 2000mm/min zu fahren. Hier gibt's den Link zum Wiki. Eine Sache würde ich gerne noch wissen: wie hast du die Firmware eingestellt? Einfach die Pins von der Heizung/dem Thermistor für Hotend 1 und 2 gleich belegt?by uGen - Extruder, Hotends & verschiedene Materialien
Re: Dual Extruder mit einem Hotend - 10 years ago
@Hux Flux: Wenn du ein G1 Fxxxx hinter die letzte Zeile anhängst, sollte der Drucker diese Feedrate bis zur nächsten Änderung übernehmen, wenn mich nicht alles täuscht... Hast du einfach mit dem neuen Material weitergedruckt oder erst mal zur Seite die Nozzle entleert? Sieht jedenfalls aus wie normal weitergedruckt und ich muss sagen, das ist ein wirklich schöner (also kurzer) Übergang.by uGen - Extruder, Hotends & verschiedene Materialien
Re: 2 Extruders, 1 Hotend - 10 years ago
Well, I thought about using two extruders to feed one hotend, but the idea never left the "thinking about" phase because I thought this method would have too many drawbacks. And then you came along to prove that it is indeed fully possible with good results. So I kept that in mind, but couldn't find the post again where you published your results and opened this thread in hopes to find it again.by uGen - General
Re: Dual Extruder mit einem Hotend - 10 years ago
Hallo Leute, da hat jemand schon genau das realisiert, worüber ihr diskutiert: Lustigerweise musste ich auch erst nachfragen... Würde mich total interessieren, wenn das weiterentwickelt wird, denn bei meinem E3D hotend habe ich kurze Übergangsphasen bemerkt, wenn man das alte Filament schnell rauszieht.by uGen - Extruder, Hotends & verschiedene Materialien
Re: Help and Advice running Reprap in University lab - 10 years ago
Hello Simon, I am in a very similar situation: as a tutor in a workshop of an art school, I helped students to build ten Mendel90's last year. These machines were supposed to be distributed across art school for the classes to use, but seemingly most of them fell into disuse. A lot of the students didn't seem to care about them after the initial rush and excitement. Tomorrow, just like you (stranby uGen - General
Re: 2 Extruders, 1 Hotend - 10 years ago
Please keep in mind, though, that the RichRap's design will not mix the colors fully. The extrudate looks a little bit like multicolored toothpaste. For even blending, you would probably need a long melt zone that additionally has to cause a lot of turbulence in the molten plastic.by uGen - General
Re: 2 Extruders, 1 Hotend - 10 years ago
@psilocin: Do you mean something similar to what RichRap has built? 3 Color Extruder Again, this is NOT about mixing the colors, but extruding multiple materials from the same nozzle instead of using several nozzles.by uGen - General
Re: 2 Extruders, 1 Hotend - 10 years ago
@aduy: You are right. I mainly considered bowden designs because I wanted to keep X carriage weight to a minimum. However, I am unsure about how reliable feeding filament into an extruder without decreasing tension on the idler first will be. Given that the idler doesn't have to sit absolutely tight against the hobbed bolt when no filament is in the extruder, though, I can imagine that this mightby uGen - General
2 Extruders, 1 Hotend - 10 years ago
Hey folks, some time ago I had the idea to use one hotend for dual extrusion. Basically, the filament change would be performed by retracting the old filament to a Y-junction and pushing the new one in. Thinking that this might not work reliably because of the plug of molten plastic needing to fit through the whole length of the hotend, this idea was abandoned after a short while. However, it tuby uGen - General
Re: High temperature stepper motor? - 10 years ago
I am thinking of rebuilding my printer (currently a Mendel-Design) as an enclosed Bowden CoreXY-bot. The chamber itself is not a problem thanks to aluminium coated styrofoam, but the X and Y carriages and the Z assembly still pose problems. The build didn't start yet, as I am busy with other stuff at the moment, but the printer is constantly being developed in my head. Well, one possibility wouldby uGen - General
Re: High temperature stepper motor? - 10 years ago
@aduy: yeah, I also would love to use polycarbonate for my printer. The only problem is that there doesn't seem to be any supplier in Europe that has it in 1.75mm. Even 3mm is hard to get and I am not willing to pay 25$ for a shipment from the US. Hope the situation improves soon.by uGen - General
Re: High temperature stepper motor? - 10 years ago
What kind of design is your printer derived from? For a H-Bot/CoreXY design, I have about figured out how to place the motors so that they are kept out of the chamber. And how do you keep parts from melting? This is one thing I couldn't figure out yet to manage with ABS parts.by uGen - General
Re: PLA on an unheated bed - 10 years ago
If you ever run into the situation that PLA doesn't stick to tape (due to size or whatever), definitely try UHU glue stick. I had to chisel parts off the platform, once even breaking the glass in the process. Also tried this with a cold build platform (just glue stick on glass) with excellent results. Other glue sticks may behave differently, e.g. PLA likes to stick to Tombow glue stick on Kaptonby uGen - General
Re: PLA on an unheated bed - 10 years ago
The only thing I can think of now is that a heated bed - and even better, a heated chamber will reduce the stresses your part will have due to temperature differences. When the entire part is kept at (or slightly below) glass transition temperature during the print and slowly and evenly cooled afterwards, it won't have thermal stresses. This is supposed to be a problem when working with acrylic gby uGen - General
Re: heated build chamber - 10 years ago
Can confirm that a design with a door or hatch retains a lot of heat...I built my hatch oven-style, which, in hindsight, was not the best idea since when opened, the hatch takes up about half a meter in front of the printer. So side-opening designs might be better for larger chambers. Sliding doors might be even better since they should not cause as much air turbulence as swinging ones. By the wby uGen - General
Re: Heated build chamber - Fridge? - 10 years ago
yup, polystyrene works really well to insulate. Additionally, a layer of aluminium foil on the inside will deflect IR radiation. That's why I chose those retrofit radiator insulation mats for my heat insulated chamber. The mats however are rather thin (3mm or so), maybe adding the thicker polystyrene tiles used in wall insulation will improve the retaining capacity even more...by uGen - General
Re: Do the belts matter? - 10 years ago
I wonder what requirements you guys with dyneema/spectra/fishing/whatever-you-may-call-it line printers have: for organic and artsy models, holding very close tolerances do not usually matter, but as soon as you want parts within close tolerances across the whole build volume, I imagine that because the line has to wind several times across the spool (and thus, the initial point of contact wanderby uGen - General
Re: Update on the E3D All Metal Hotend (Now finally shipping!) [Lots of pictures] - 10 years ago
@Destroyer2012: I am running my E3D inside a chamber @~45°C max; works pretty well and I have not run into problems yet. Guess a constant airflow at maximum fan speed does the trick. @p40whk: I am using an own custom direct drive design. Basically every J-Head mount compatible extruder should work, but if you use flexible/soft filament a lot, I would recommend looking for an extruder where the lby uGen - General