Has anyone sanded base before putting on the clear coat?

 

Yes I have, But it was a solid color and it was needed to repair a mistake. After another coat, the car was cleared. I've heard of sanding in between clear coats but not the basecoat paint.

 

x2
Is the base messed up or did you lose the recoat window for the clear?

The best bet is to look at your basecoat tech sheet and see what they say to do after you lose the window, that would be where sanding or scuffing and whatever else you have to do would be mentioned.
Normally if you sand base you have to basecoat again before clear, the clear needs a chemical bond to the base or it can delaminate.

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