Ultimaker Original+ Beginner's Calibration Question

[nemo 0]

I am just starting out with 3D printing and recently bought an Ultimaker Original+ kit. I just finished assembly the other day and have done a couple of quick test prints. Over all, I'm pretty pleased with the quality considering my lack of experience. I am seeing a couple of artifacts, however, and I wanted to see if someone here could take a look at a test print and tell me if I haven't got the calibration right, am having some other issues that I need to address, or if everything looks within tolerances. Basically, before I get too far into this, I want to make sure I've set up the machine correctly and am working from a solid base.

The main thing I have noticed is that the strands that are laid down are sometimes either missing or very thin. I see this especially in the first layer on the bed. I've included two pictures of the bottom of the MinCalTest print at different angles so you can see it. I didn't have the gcode file on my SD card, but I found the STL file referenced on the forum and printed that on the Normal print quality setting. The prints were done using PLA, with the bed and extruder set to the PLA default temperatures. I didn't use any glue or tape on the bed (but the adhesion seemed to be good, and I saw no warping).

From the top layer, there are two things I wanted to check on. The first is the amount the cross hatching pattern is visible. I expect to see it to some degree given how the process works, but I wanted to make sure the amount I have is within the expected range for the machine. Second, it looks to me like I have a tiny bit of eccentricity in the circular hole. Again, is that to be expected, or are there some problems I should be looking for?

Thanks in advance!

[IRobertI 516]

I would suspect you have a little bit of backlash going on. Rather than re-typing I'll be lazy and just link these two sections for you to read through. Basically I think you need to tighten the short belts a little bit:

http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#circles

http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#wallspace

The amount of crosshatching you have on the top layer looks normal to me. It will always be present to some degree, it's the nature of the beast.

[nemo 0]

I tightened the belts like you suggested and reprinted. It's clearly better now. The pattern on the first layer is nice and regular, and the circular hole looks perfectly circular to my eye. Thanks for the advise and the helpful links!