Hi – OK, so this is the kind of knife you need to get yourself:
It’s a good, solid tool, with a sturdy handle, which is exactly what you need to control your lump of glass paint and also keep your palette tidy.
And those dainty knives like this one here or here: well, I’m sure they have their uses, like, if you have one, maybe you can keep it for when you come to paint or silver stain with oil (I’ll tell you about that another time).
But for your lump of glass paint, dainty knives are just not good enough.