The root of the problem has been described well by others already.Your top plate is not lining up on the vertical with the bottom plate.Something is off.I believe the machining must be poor on this design .But you can fix it with the help of a big square ,or easier make a jig byt puting together two plywoods that form an "L" shape and they form a true 90 degree angle.Then put your stand in there on it's side and make apropiate adjustments,until both
plates touch the plywoods.When they erect buildings they could easily run into same problem but they don't ,right?
George
plates touch the plywoods.When they erect buildings they could easily run into same problem but they don't ,right?
George