Oh yeah, if you want it to look nice, it takes time. But I'm sorry, I've never used Tru Oil so I can't offer any advice about sanding between coats; you may want to check out some YouTube videos. With the lacquer clear coats I use, I've done it both ways; sand between coats or pile all the clear on at the end, then sand. The finished product seems the same either way. Keep up the good work, and you'll have an SG to be proud of.