AgelessRevision

What about in your Z dimension Framar? What do you think is causing your dimensional inaccuracies? I think faster print speed might contribute to inaccuracies in X and Y, i'm using 30 mm/s and get errors within the .2-.3 range. Also, for me since i'm laying down 15 lines per layer at 0.8 mm line widths, I imagine the error is larger in that direction since the line widths i'm using are pretty fat. Let me know if you solve your dimensional accuracies and what factors you changed if you don't mind sharing. FIX: In my previous post I said I was printing 0.7 mm line widths and 0.8 mm layer heights, but I mixed up the numbers, I'm actually using 0.8 mm line widths and 0.7 mm layer heights.

Have you solved the dimensional inaccuracy issue yet? I too am working on a UMS5 and facing similar issues in printing out standard small rectangular prisms. I'm using a 0.8 mm nozzle, printing abs. The part I'm working with is a 35 mm x 12.0 mm x 4.2 mm block set at 100% infill, 0.7 line width and 0.8 mm layer heights. I found that tweaking the horizontal expansion setting can alter the accuracy of the x and y dimensions, but I have not found a solution for the z-axis yet. The dimensional inaccuracies i'm facing are 0.2 mm off in the z- dimension, and .35mm in the y.

Interesting, I was just messing around with some line settings as you have suggested and found that changing line width from 0.8 to 0.77 changed the number of sliced lines from 14 to 15. I did not observe any effects or visual changes in the lines from changing infill line width to even a small value of 0.2. What's even more interesting is that the horizontal expansion setting also changed the total number of sliced lines. I set line width and infill line width to 0.8 which originally produced 14 lines, but after changing horizontal expansion to 0.15, the line count increased to 15!

Thank you peggyb for your response. I see that you set line width to 0.75 and infill line width to 0.8. That's interesting, when I set line width to 0.75 and infill line width to 0.8 I get 15 lines also, like you have shown. With line width set to 0.75, and infill line width set to 0.8, do you think every line that is laid down will be about 0.8 mm? I'm not sure how infill line width differs from line width. Thanks again!

Hello Everyone, When printing out a basic rectangular prism of dimensions 35 mm x 12.0 mm x 4.2 mm ( x, y, z), @ 0.8 mm line width, laid in lines along the length of the part with 100% infill density, I expect the lineCount to be equal to: lineCount = (y_dim_length)/(line_width) = (12.0 mm) / (0.8 mm) = 15 lines. But for some reason I always get 1 line less than I expect. Here is a picture to illustrate more clearly. If you count the number of lines in that rectangle it comes out to 14. I am currently working with Cura 3.6 on an UMS5, although before I was working on a UM2+ extended and had the same issue. I imagine this problem is not related to the printer, but my inability to operate cura appropriately. I thought maybe there were some settings that somehow would make 14 0.8 mm lines flatten out to be 12.0 mm, and caliper measurements report 11.8 mm which isn't to bad I suppose. I also tried slightly making the y-dimension larger, for example changing the y-dim length from 12.0 mm to 12.2 mm and it indeed does slice 15 lines instead of 14, but the actual dimensions measured with a caliper increased to 12.5 mm. Do you guys know what's going on here? My end goal is to have dimensionally accurate y-length of 12.0mm with 15 lines at 0.8 mm line widths. Much appreciated

Thank you tinkergnome for your detailed response. Changing that value from 120% to 100% solved my problem!

Hey guys. I was wondering how cura slices the first layer of the print. Dimensionally, it's not corresponding to the line width I have chosen and the overall length which to lay the line. On top of that the line width from this first layer, changes in every subsequent layer. To illustrate, I'm printing a 35 mm x 12 mm x 4.2 mm ( x,y,z) rectangular prism, with line width set to 0.8 mm. In cura, the first layer only slices 12 lines when I expect 15 to account for y-dimension length ( 0.8*15=12 mm). The layers after the first all have 14 lines, which is closer to the 15 I expected, but the fact that the number of lines has changed is confusing me. This causes the bottom of the rectangular prism to be fatter then the rest of the part. Even though it only prints 12 lines for the first layer, they are significantly fatter, definitely more wide than the input 0.8mm. For my application its really important for all the layers to be exactly the same. I couldn't seem to find any settings in Cura where I could make sure the number of lines per layer stays consistent. Any assistance would be greatly appreciated!