Thick lines outside - Every 9/10mm on prints.

[MisterJRJA]

Hi folks. New here and relatively new to 3d printing so please be gentle!Printer - Ender 3Issue - As you can see from these prints attached I am having some lines occur on the outside of the print literally every 10mm like clockwork. This occurs on both 90degree and curved prints.I’ve read up into this and think it may having something to do with the z-axis? In terms of settings I have used my own and then someone else’s profile from YouTube and still get the same issues.The rest of the print is absolutely fine in terms of sturdy-ness. Please help!!