Dissolve shader on low poly models problem

So I watched brackeys tutorial on making a dissolve effect using shader graph and managed to get it working after trying it out myself. It worked alright when using the preview sphere, cube and the like but when I used a low poly gun model, large parts of it dissapeared at once and no matter how high the noise scale it still dissolves piece by piece. Now I have minimum knowledge about shaders but I assume it's happening due to the model having little changes in alpha.

Is there any way to achieve normal dissolving on models like these? Even better if instead of noise based dissolving, I could dissolve the model out top to bottom and vice versa

 

Try to use procedural noise generated from fragment local position.