I've fitted a waste unit to a sink and now need to fit the trap etc, as shown in the pics, the bottom of the waste unit is exactly the same size as the pvc pipe so the pvc nut wont reach the thread of the waste unit and connect properly. It's a standard size trap and waste I was told, am I missing a part? Or do I need a smaller waste unit/larger trap unit? I'm sure it's obvious but I know nothing about plumbing & waste units etc so any advice is appreciated,.
Cheers