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Morgan, Wally, and many others too strange and wonderful to be described here. Previously named "Polar bots and Robot Arms"
Re: probléme de chauffage - 11 years ago
l'alim se met en sécurité parce qu'elle ne peut delivrer assez de courant ???by alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Timing belts - what's the story? - 11 years ago
aduy wrote : > the reason i say this is because the square tooth profile does not mesh with the teeth as well as the gt2 belt. > take a look at this and read the description of each .That is PR bullshit from a manufacturer pushing his own standard (GT2). T profile is involute like a gear, and there is a pitch correction to reduce backlash at maximum. from SDP technical handbook onby alj_rprp - General
Re: Fastest stepper driver? - 11 years ago
Well steppers may lose most of the torque at high speed, but you mostly need torque when accelerating so that is not a so big deal at constant speed. However if you want to run that fast, accelerations ramps are mandatory are you will need something like grbl on a more capable hardware than arduino /me thinks.by alj_rprp - General
Re: Gizmodo "Why 3D Printing is Overhyped" - 11 years ago
jzatopa Wrote: ------------------------------------------------------- > Joe public doesn't know what 3d printing is or > that it even exists yet. In my experience, this is changing very rapidly. 2 years ago, you would have been right, but not anymore. And I live in a place which, while not really backward, is far from being in the front of tech awareness.by alj_rprp - General
Re: Timing belts - what's the story? - 11 years ago
bend (turning) radius is critical on timing belt for accuracy and lifetime, but also as you increase speed it needs to be increased too. Bend radius on the spine needs to be at least 1.5x the inner one, or you will break the tension wires. 12 teeths on T5 is indeed a good minimum,16 on T2.5. The value can change depending of manufacturer thoughby alj_rprp - General
Re: Prusa Nozzle Released - 11 years ago
prusajr Wrote: ------------------------------------------------------- > alj_rprp Wrote: > -------------------------------------------------- > ----- > > > > Received mine today (0.4). ... > > Now, the PLA i tested ooze really a lot at > 230°C. > > The same plastic dont ooze at all with a J-head > at > > 215°C. > > > > tested extrusionby alj_rprp - General
Re: Prusa Nozzle Released - 11 years ago
prusajr Wrote: > Can you post a pic of the setup, can the air flow > under the carriage? That is kinda needed if you > want passive cooling. > If not, try experimenting with the included fan. > > I print here at 245°C. But as I stated, heat was > somehow misteriously travelling to the hobbed > bolt, so I cool the bolt. > > Also I noticed It doesnt like extremely qby alj_rprp - General
Re: Marlin Board Selection for Homemade Electronics. - 11 years ago
ShadowRam Wrote: ------------------------------------------------------- > > dle/ > > I'd be surprised if anyone could build this entire > setup homebrew for <$155. at $155 this is not even a very good price. you can find better eg on ebay, while keeping quality stuffby alj_rprp - General
Re: Aluminium extrudé - 11 years ago
au canada misumi vends aux particuliers, contrairement à l'europeby alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: PLA not sticking to bed - 11 years ago
Martin_G3D Wrote: ------------------------------------------------------- > Spazmor Wrote: > -------------------------------------------------- > ----- > > Hi, > > > > New PLA sliding off bed. Have tried different > bed > > temps 55c & 85c > > Any advice? > > No heating, cooling. PLA have a different rules - > more fast it become cold thanby alj_rprp - Reprappers
Re: Bronze Sleeve Bearings - 11 years ago
while friction is independant of the area of contact, there is other loss forces that are not. especially with bushings, you can have sucker effects which are very dependant of the area in contact and especially of the smallest contact areas without micro scars. Which is why plain bushings works better with coarser smooth rods. For sintered bushings, the smoother the rods, the lower grade of oilby alj_rprp - General
Re: Jhead MK V thermistors - 11 years ago
from maker blog, the MK5b use : Part Number: 104GT-2 Manufacturer: Semitec Description: NTC 100k ohm 3% Tolerance: 3% Data Sheet: High Heat-Resistance and High Sensitive Thermistor Diameter of Glass Bead: 1.35mm +-0.15mm Length of Glass Bead: 3mm +-1mm Lead Length: 45mm +-1mm Lead Diameter: 0.15mm to 0.18mm If using Sprinter firmware, select temperature table #5. Now, good german copies of theby alj_rprp - Reprappers
Re: Comment connaitre la quantité de plastique nécessaire à partir de STL - 11 years ago
la derniere ligne du fichier gcode est du genre : ; filament used = 408.7mm (3.0cm3) sinon, en sliçant directement depuis pronterface ou repetier host avec slic3r en backapp, tu as l'info. Même si il a une interface, slic3r est normalement utilisé en background app.by alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Comment connaitre la quantité de plastique nécessaire à partir de STL - 11 years ago
slice avec slic3r, il donne la quantité de filament nécéssaire à la fois en cm3 et en longueur suivant le diametre. De toutes façons ça dépend de l'infill, donc il faut slicer le stl d'abord.by alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Update on the E3D All Metal Hotend (Now finally shipping!) 
[Lots of pictures] - 11 years ago
SanjayM Wrote: ------------------------------------------------------- > Interesting point alj_rprp. > > I will see what I can do to stress test that. > > Another thing is that PFA is a bit less compliant > that PFA - which means moving the print-head needs > more force. Negligible in 1.75mm systems, but > actually a noticeable factor in 3mm tubes. Just checked, PFA iby alj_rprp - General
Re: Update on the E3D All Metal Hotend (Now finally shipping!) [Lots of pictures] - 11 years ago
problem of teflon (PTFE) in bowden systems is plastic memory. When you bend a teflon part, the place that bended become a little less elastic as deformation are not 100% in the elastic domain. Not much a problem as we have very little load, but it means that fatigue failures can occur. Never used PFA so dont know if better.by alj_rprp - General
Re: [rech] personnes intéressées pour travailler un concept de récup PLA - 11 years ago
une bonne solution serait de baser la vis de l'extrudeur (qui est la partie critique) sur une vis de de robot ménager Par rapport à un foret hélico, le pas de l'hélice est variable ce qui va comprimer la matière celle la en particulier me parait bien Seul défaut, elle sont plutot courtes, ce qui ne nous arrange pas. A noter aussi que certains extrudeurs pour machines à injecter utilisenby alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Retour d'expérience sur la fabrication d'une reprap prusa v2 - 11 years ago
les kits de gadget3d et reprapdiscounts sont équivalents, dans les kits avec arduino, il y a par contre une difference de taille : - Dans les kits de fabster (gadget3D), c'est une vraie arduino mega + la ramps est complete avec tous les headers. très bonne qualité de fab des deux cartes, radiateur sur le mosfet du bed, livré avec un ventilo surpuissant pour refroidir la carte. - Dans les kits dby alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Reprap Design Strategies - Ultimaker - 11 years ago
dont know about GT2, it is an US standard, but T2.5 is available in steel : I used it in kevlar versions too. Anyhow, it is just a matter of adjusting the width of belt, we can use fiberglass too. Minimal inner radius for metal T2.5 is R6 which is fine with what we have now. outer radius (cambering on the spine) is much bigger, but that is not a problem. A for expensive, T2.5w6 is 5€/meterby alj_rprp - Reprappers
Re: Fabrication Prusa i3 - 11 years ago
drv8825 monté avec protections : mais le A4988 est suffisant dans la plupart des cas avec nos NEMA17 : 2.2 A par phase avec radiateur.by alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Dreaming of a Static Motor Arrangement and Less Vitamins - 11 years ago
REPRAP SQUAD Wrote: ------------------------------------------------------- > The only problems with the : Rigid chain actuator > if I remember right. Is that it has really tight > tolerances and requires a lot of stregnth in the > parts that make up the sum. If it could be > simplified in build and manufacturing you would be > on course for a promising build. Taking that > cby alj_rprp - Developers
Re: Reprap Design Strategies - Ultimaker - 11 years ago
I will probably try make a corexy machine, that seems a very good solution for me, the raking equilibrium lessen the needed precision, especially with a small bowden tube and 2 or 3 heads. Quite cheap and good precision achievable with only DIY tools. For the belts, one thing to be aware of is that the same belt (say T2.5 or GT2) exist in at least 2 versions with either plastic (high flexibilityby alj_rprp - Reprappers
Re: problems with printing quality - two cooling fans? - 11 years ago
60° is good for first layer. After on my prusa I use 50°C I Have a config with 2 small fans btw, mounted at 90° from each other. But while one is oriented toward the noozle, the other's job is to blow into the vents of the JHead. O.4 layer with a 0.5 noozle is the maximum you should use (0.8x), and if you use 100% infill, the 50 mm tower is also a measure of the accuracy of extruder steps, mucby alj_rprp - General
Re: Fabrication Prusa i3 - 11 years ago
la question de la précision est simple : Les moteurs pas à pas bipolaires (4 fils) sont en général des 1.8° ou 0.9° de precision. donc pour l'axe Z, pas de problème, même en pas simple et une vis de M8 (1 tour = 1.25mm), ça donne : 1*1.8/360*1.25 = 0.00625 ce qui est une précision très confortable. Pour les axes X et Y, ça donne pour une poulie de 12 un périmetre de 12*3.14 = 37.67 mm pour unby alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Aide Prusa Mendel Paris - 11 years ago
ça parait beaucoup, mais si le bed est pas isolé, il peur avoit facile 90°C au thermistor et moins de 60 sur le dessus de la plaque de verre. Qd j'ai rajouté mon bed chauffant, avant de mettre les plaques de lièges, il fallait chauffer à 70°C. avec le liège, à 50°C c'est bien. Et isoler diminue le temps de chauffe par 2 mini. Cela dit, le PLA, s'il est de qualité correcte, s'imprime très bien suby alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Need a hot end . More reliable then J head? Bowden drive - 11 years ago
I wonder if we could not use this kind of peltier cooler to create a very sharp controlled transition zone and reduce the heatsink size and weight : This particular one is not adapted to high temps but such modules exist. A peltier ring from china is less than 10€by alj_rprp - General
Re: Bi-Cube contest: ends 11th May - 11 years ago
That one was a copperplated B*tch to do. Not only that but my bed MOSFET decided to take a break for a smoke. was that bad ? Still not there and dont laugh at the overly large brim, but no heated bed is really a handicap. The key seemed to print hot and hollow. Quality is so-so but the best i can do before repairing the bed. PLA, extruder 0.4, 0.25 layers at 200°C. 25 mm/s. mirror + haiby alj_rprp - Competitions
Re: 3dstuffmaker votre avis? - 11 years ago
Quand j'ai acheté ma prusa en février, j'ai éliminé ces 2 là rapidement après recherche sur les forums. Le feedback était pas bon. J'ai acheté ma prusa chez , j'en suis content, et très bon support client, j'ai eu 2 questions concernant le thermistor, reponse mail sous 2H !!! . Bonne qualité dans l'ensemble, même si j'avais 2 pièces légèrement deformées (pièces moulées pas imprimées). j'ai ausby alj_rprp - RepRap Groupe d'Utilisateurs Francophone
Re: Printing with polyurethane - 11 years ago
I'am not a chemist, but 3 points to keep in mind : - Polyurethane is a vast family where some are thermoplastic hence usable for reprap, other are thermosetting and even if they can be melt (some may not) they would lose their caracteristics. - They may contain nasty stuff either as base component (some isocyanates) or additives. - If they degrade (over 250°C ?) , they can release lot of CO.by alj_rprp - General