chris

Joergen, first thanks for the detailed reply. Sorry for my nescience, but what exactly is the "set screw" at the stepper motors? In addition, shrinkage also depends on the cooling, especially the direction your fan is blowing from is probably show more shrinkage, since the fan cools it faster, so it shrinks faster, or the other side of the fan shrinks more because the plastic is setting slower, and has more time to affect the layers below... could be one or the other... I know ABS that is cooled harder shrinks more. I am sure your explanation are correct. I agree with different shrinking factors cause of diverse cooler direction. Make sense, absolute. I think I will do further tests the next days. Another thing I´d like to know is, what do all the people that download stl´s at e.g. Thingiverse. Are all the users affectedly to scale the stl´s, when they wanted the parts to be accuracy. For example to things that should filt together? Thats not nice, isn´t it. That only works, if you know your machine (and PLA) very well. Thanks in advanced for the replies. Chris

as I wrote above, I did a test with a caliper. I measure the distances, the extruder went. And there were nearly the same tolerances as if I printed. I don´t want to close my eyes from shrinking, but I don´t understand. Another thing is, that the y tolernaces are higher. When it´s a shrinking problem, would it not be the same on both axes?

yesterday evening I started a test. I slowly increased the steps/mm value. Default was 78,74, like you said. I had a plate 30x30. At exact X80,15 and Y 79,85 my plate was really 30,00x30,00. Thats great. BUUUUUT then I printed with the same values a plate 50x50. It was much to big. At about 53x51. So I don´t think I have to play with this value. Ok it was just atry :lol: How exact are your prints for example. I can´t believe that I am the only one with such a problem. Thanks Chris.

sorry, but is there any other idea, what my problem is about?

Hi Joergen, thanks for your reply. I don´t think, that only shrinking can be the problem, cause the measuring with the caliper is nearly the same as print difference. Please don´t fix me on the values that I write above, cause that was only right fast without looking to my records. The unaccuracy is not ever the same. Its not linear. Thanks Chris

where can I see if the value is right. In a generated g-code, there is only M92 for the extruder motor, but not for the x and y axis. How to get sure i am running the newest firmware. The only thing I can see, is the list in the printer interface. It says "Marlin 1.0.0 RC2" and M92 X78,74 Y78,74, but not 78,7402.

Thanks Daid, but what is the right value, that I should use?

Hello everybody, I got a big problem with the accuracy of my parts. My printed parts are always to small. For example a plate 50x70 is just 49,6x69,4. So I do a little further tests and mounted a caliper to my machine, started Cura print run and travel defined distances like 0,1, 1 and 10mm. The results affirmed my prits. The distance at a travel from e.g. 10mm is just 9,65. And the travel from 1mm is just 0,89. So I go and calibrate the hole machine. Loosen the pulleys, adjust the rods and so on. My machine is 100% straight (hope so ). What can I do to get 10mm, when I say to Cura travel 10mm :evil: Where is my mistake. Is it possible, that the steper motors dont work correct (can i change settings anywhere?) and how many mm must be one rotation Please help me to get accurace parts. Thanks you Chris

tomorrow I plan to measure the accuracy of the traveling distance of the x and y axis. I can´t believe its fully accurat. For me 0,1 would be enough. When you are right, and the software caused the problems, why does nobody work on it, or do they . : Please tell me something about the problem, if you got an idea. The other thing I would really like to know. Is there nobody else you got the problems. What about printing things from Thingiverse. When everyone has the same problem, everybody needs to drill the holes after printing, cause a 3mm hole is max. 2,5mm. Thanks too all.

Hi guys, i hope my question is not too stupid, but I think it is! I got some new filament from Faberdashery. Its really great. But I got the big problem that its coming without the spool. And heres my question: How to get the filament reasonableon the old spool. Its twisting and fully out of controle . What to do. Thanks for your answers. Chris

Hi community, i´d like to talk about an interesting theme. The accuracy of our printing parts. Something for your information. I´am an engineering in development and design and design products, for example pumps for the gas analytic market. I bought the ultimaker 6 weeks ago, because I´am planing to print prototypes of my designs by myself. Then check the parts for assembly, before I order an injection mould for thousens of euros. So far so good. Now I got the big problem, that the printed parts are not accuracy enough to assemble them safety. I need an accuracy about 0,1mm. I think that is not a tall order. I started to print easy parts, to research the accuracy. For example an rectangle 30x30x5. When the printer is finish, the part is about 29,5x29,3x5. The z-axis is very accuracy. Thats enough. But what about the x- and y axis. For my need it´s very bad. When I scale the part to for exmple 30,5x30,7x5 it fitts perfectly. But sorry, that´s not the plan, to scale every object before priting. Lets start a discussion, how accuracy your parts be. Maybe print rectangles, too, and tell me about this. Another thing that I hope for, are tips and tricks too increase the accuracy. I´am a little bit frustrated, sorry. Thanks to all Chris

Thanks for the answers, @ Daid: I don´t completly understand what you explained. Should I play with the top and bottom Layer thickness, or is it the best to leave it at 0,6mm? Another thing, wich "destroys" my surface, especially the top, are the little lines from the extruder travelling. In the expert settings (Cura) I don´t tick "Retract on jumps only". In my understanding, that meens that every travel will be retracted, isn´t it. The printer do the retraction, when it´s traveling, but there are still lines! What to do. Thanks Chris

Hi guys, by now I get more and more closer to my Ultimaker every day. Thats nice and makes me happy. But I got a question regarding the bottom and top surfaces. What quality is possible. Today I printed my first companion cube (had it from thingiverse) and the sides were awesome. Really smooth surfaces. Looks great. But bottom and top looks like a mess. At the bottom you see the 45° lines. It´not filled 100%. But what to do, to get it filled. And the top is not so smooth, too. Has anybody some input for me to improve my top and bottom surfaces to perfection :-) Thanks in advanced. Greetings Chris

Hello Daid, thanks a lot, it works. Now I have to try out, how the results are with my new feedrate of 853.09

Hello together, I am searching about an hour for a clear answer to my question, but I think everyone has a different method. But I am new and I want to do it pretty right . The theme is the calibration of my Utimaker with e.g. the Cura procedure. What I don´t understand is, must I do the extrusion of e.g. 100mm filament through the hot end, or should the filament walk free in the bowden tube. I think (and read it) theres a difference between the both methods. And then, when I got the right lenght, what must I do, to get the right E-steps number. Is there a formula? Sorry for my newbie stupidness. Thanks Chris.