I am staining some spruce with Minwax Oilbased Dark Walnut Stain. I initially use wood conditioner, then I apply the stain. After 10 minutes I wipe of the excess stain. I was just wondering, if I don't want to apply a second coat of stain, do I really need to wait 8 hours to apply polyurethene over top of the stain? Can I put oil based polyurethane right after I wipe of the excess stain?