print quality - What causes ripples on part of first layer? - 3D Printing Stack Exchange

I'm having issues with ripples on the first layer of big flat prints. The initial corner of a big flat print is fine, but then ripples begin to form as shown in the screenshot. I'm just a newbie

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print quality - What causes ripples on part of first layer? - 3D Printing Stack Exchange

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Any ideas what would cause these ripples? : r/3Dprinting