If you are only planning on cutting paper thin Items some like this would have been better for you..

https://www.ebay.co.uk/itm/SIGN-VINY...cAAOSw9TFdPEQm

Anything like thick card or cardboard, that's when off sets come into play, the deeper you need to cut into the material the further the tip of the blade has to be away from the centre of the shaft.

Think of it as having a Stanley knife and trying to cut through a 4mm piece of cardboard but hold the knife in a straight upright position you will struggle, but if you tilt the knife say 65 degrees it will cut easily..