I so far only managed to make the info_paint_sprayer spray like a horrific messy everywhere in every direct mist, and a violent torrent of gushing gel in a single direction. What I cant figure out is how they make a single massive blob of gel pop out every so many seconds like someone threw a terrifying water balloon of deadly science at my face.

You need to spawn a prop_paint_bomb using a point_template

You could acually look at the instances/p2editor/paint_dropper_bomb.vmf instance for an example of the logic you want. You don't want to use the actual instance (it has lots of redundant logic like the counter and branch). You want to respawn the dropper after the bomb fires the OnFizzled or OnExploded outputs, since in Valve's maps they only drop one bomb at a time.

i thought the paint bomb was something else, I will try this tommorow

Yep, it's as simple as using a point_template to spawn a prop_paint_bomb. If you want it to self-sustain, just use a logic_timer and you're good to go.