Very strange repeating pattern

[Bad_Mechanic 0]

So, this is a strange one. For the past several days I've been trying to figure out why I kept getting a strange pattern in the Z axis on my print. I tried a lot of different things from very conservative profiles with low speed and jerk settings, to the default profile, and  several other recommended profiles other people recommended. I also checked the printer over physically to make sure everything was tight. When I noticed the pattern was identical regardless of the settings, I suspected it might be Cura itself doing something. I installed Slic3r and mirrored the settings as closely as I could, and the print was complete free of that pattern (see attached pictures).

 

Right now I'm not sure how to proceed with troubleshooting this problem.

[Smithy 1,144]

It this the same model?

[Bad_Mechanic 0]

Just now, Smithy said:

It this the same model?

Sorry, yes it is. It takes 5.5 hours to print, so I generally stopped the print once I could see whether or not the pattern was there. So that picture is basically the bottom 1.5cm of the complete model.

[Smithy 1,144]

Ok, was irritated because it looks different. 

I had a model some months ago which had similar issues, but only this specific model and I never found the reason. Also sliced with Simplify3D had the same issues, so it was different from your issues here.

[Bad_Mechanic 0]

Yeah, sorry about that. I've been thinking about this problem for so long now that it didn't even occur to me that the prints looked different.